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Ramos LA, Ulic SE, Romano RM, Beckers H, Willner H, Ge M, Tong S, Della Védova CO. Dimers of perhaloacetyl cyanides: CClF2C(O)OC(CN)2CClF2 and CF3C(O)OC(CN) 2CF3. preparation, properties, and spectroscopy. J Phys Chem A 2014; 118:1721-9. [PMID: 24533467 DOI: 10.1021/jp4127732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The vapor of the new compound 1,1-dicyano-2-chloro-2,2-difluoroethyl chlorodifluoroacetate, CClF2C(O)OC(CN)2CClF2 and of the known 1,1-dicyano-2,2,2-trifluoroethyl trifluoroacetate, CF3C(O)OC(CN)2CF3, were investigated using vibrational spectroscopy tools. The existence of rotational isomerism was confirmed for CClF2C(O)OC(CN)2CClF2 when the matrix isolated compound was examined in combination with the computational results applying quantum chemical models. From the four conformers gauche-syn-gauche, gauche-syn-anti, syn-syn-anti, syn-syn-gauche (the used nomenclature is with respect to the ϕ(ClC-C(O)), ϕ((O)C-OC), and ϕ(OC-CCl) torsion angles, respectively) predicted for CClF2C(O)OC(CN)2CClF2 the first two forms can be evidenced using Ar-matrix IR spectroscopy, with the first one being the most abundant at room temperature. On the other side, the results obtained for CF3C(O)OC(CN)2CF3 reveals the existence of only one syn-syn-anti form. CClF2C(O)OC(CN)2CClF2 melts at -40 °C and its vapor pressure was fitted by the equation ln p = -4732.6 (1/T) + 10.75 (p [Atm], T [K]) in the range -20 to 20 °C. Its extrapolated boiling point is 167 °C. The first ionization potentials occur for CClF2C(O)OC(CN)2CClF2 and CF3C(O)OC(CN)2CF3 at 12.13 and 12.43 eV, respectively, and were attributed to the ejection of electrons formally located at the carbonylic oxygen lone-pair electrons (nO). The proposed interpretation of the photoelectron spectrum is consistent with related molecules reported previously, and also with the prediction of Outer Valence Green's Functions (OVGF).
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Affiliation(s)
- Luis A Ramos
- CEQUINOR (UNLP-CONICET), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata , 47 esq. 115, 1900 La Plata, República Argentina
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Ramos LA, Ulic SE, Romano RM, Beckers H, Willner H, Della Védova CO. Matrix Photochemical Study and Conformational Analysis of CH 3C(O)NCS and CF 3C(O)NCS. J Phys Chem A 2014; 118:697-707. [DOI: 10.1021/jp4110085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Luis A. Ramos
- CEQUINOR (UNLP-CONICET), Departamento de Química,
Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República Argentina
| | - Sonia E. Ulic
- CEQUINOR (UNLP-CONICET), Departamento de Química,
Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República Argentina
| | - Rosana M. Romano
- CEQUINOR (UNLP-CONICET), Departamento de Química,
Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República Argentina
| | - Helmut Beckers
- Fachbereich
C - Anorganische Chemie, Bergische Universität Wuppertal, 42097 Wuppertal, Germany
| | - Helge Willner
- Fachbereich
C - Anorganische Chemie, Bergische Universität Wuppertal, 42097 Wuppertal, Germany
| | - Carlos O. Della Védova
- CEQUINOR (UNLP-CONICET), Departamento de Química,
Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República Argentina
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Ramos LA, Ulic SE, Romano RM, Vishnevskiy YV, Mitzel NW, Beckers H, Willner H, Tong S, Ge M, Della Védova CO. Chlorodifluoroacetyl isothiocyanate, ClF2CC(O)NCS: preparation and structural and spectroscopic studies. J Phys Chem A 2013; 117:5597-606. [PMID: 23746282 DOI: 10.1021/jp403549f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Chlorodifluoroacetyl isothiocyanate, ClF2CC(O)NCS, was synthesized by the reaction of ClF2CC(O)Cl with an excess of AgNCS. The colorless product melts at -85 °C, and its vapor pressure follows the equation ln p = -4471.1 (1/T) + 11.35 (p [atm], T [K]) in the range -38 to 22 °C. The compound has been characterized by IR (gas phase, Ar matrix, and matrix photochemistry), by liquid Raman, by (19)F and (13)C NMR, gas UV-vis, and photoelectron spectroscopy (PES), by photoionization mass spectrometry (PIMS), and by gas electron diffraction (GED). The conformational properties of ClF2CC(O)NCS have been analyzed by joint application of vibrational spectroscopy, GED and quantum chemical calculations. The existence of two conformers has been detected in the gas and liquid phases, in which the C-Cl bond adopts a gauche orientation with respect to the C═O group; the C═O group is in syn- or anti-position with respect to the N═C double bond of the NCS group. The computed ΔG° difference between these two gauche-syn and gauche-anti forms is ΔG° = 0.63 kcal mol(-1) in the B3LYP/6-31G(d) approximation. The most significant gas-phase structural parameters for gauche-syn ClF2CC(O)NCS are re(NC═S) 1.559(2) Å, re(N═CS) 1.213(2) Å, re(N-C) 1.399(7) Å, re(C═O) 1.199(2) Å, and ∠e(CNC) 134.7(13)°. Photolysis of ClF2CC(O)NCS using an ArF excimer laser (193 nm) mainly yields ClF2CNCS, CO, and ClC(O)CF2NCS. The valence electronic properties of the title compound were studied using PES and PIMS. The experimental first vertical ionization energy of 10.43 eV corresponds to the ejection primarily of the sulfur lone-pair electrons of the in-plane nonbonding orbital on the NCS group.
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Affiliation(s)
- Luis A Ramos
- CEQUINOR (UNLP-CONICET, CCT-La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República Argentina
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Ramos LA, Ulic SE, Romano RM, Erben MF, Vishnevskiy YV, Reuter CG, Mitzel NW, Beckers H, Willner H, Zeng X, Bernhardt E, Ge M, Tong S, Védova. COD. Spectroscopic Characterization and Constitutional and Rotational Isomerism of ClC(O)SCN and ClC(O)NCS. J Phys Chem A 2013; 117:2383-99. [DOI: 10.1021/jp400281g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Luis A. Ramos
- CEQUINOR (UNLP-CONICET), Departamento
de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República
Argentina
| | - Sonia E. Ulic
- CEQUINOR (UNLP-CONICET), Departamento
de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República
Argentina
- Departamento
de Ciencias Básicas, Universidad Nacional de Luján, Rutas 5 y 7 (6700)
Luján, Argentina
| | - Rosana M. Romano
- CEQUINOR (UNLP-CONICET), Departamento
de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República
Argentina
| | - Mauricio F. Erben
- CEQUINOR (UNLP-CONICET), Departamento
de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República
Argentina
| | - Yury V. Vishnevskiy
- Universität Bielefeld, Lehrstuhl für Anorganische Chemie
und Strukturchemie, Universitätsstraße 25, 33615 Bielefeld,
Germany
| | - Christian G. Reuter
- Universität Bielefeld, Lehrstuhl für Anorganische Chemie
und Strukturchemie, Universitätsstraße 25, 33615 Bielefeld,
Germany
| | - Norbert W. Mitzel
- Universität Bielefeld, Lehrstuhl für Anorganische Chemie
und Strukturchemie, Universitätsstraße 25, 33615 Bielefeld,
Germany
| | - Helmut Beckers
- Fachbereich C -
Anorganische
Chemie, Bergische Universität Wuppertal, 42097 Wuppertal, Germany
| | - Helge Willner
- Fachbereich C -
Anorganische
Chemie, Bergische Universität Wuppertal, 42097 Wuppertal, Germany
| | - Xiaoqing Zeng
- Fachbereich C -
Anorganische
Chemie, Bergische Universität Wuppertal, 42097 Wuppertal, Germany
| | - Eduard Bernhardt
- Fachbereich C -
Anorganische
Chemie, Bergische Universität Wuppertal, 42097 Wuppertal, Germany
| | - Maofa Ge
- State Key Laboratory for Structural
Chemistry of Unstable and Stable Species, Beijing National Laboratory
for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, Peoples
Republic of China
| | - ShengRui Tong
- State Key Laboratory for Structural
Chemistry of Unstable and Stable Species, Beijing National Laboratory
for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, Peoples
Republic of China
| | - Carlos O. Della Védova.
- CEQUINOR (UNLP-CONICET), Departamento
de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República
Argentina
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5
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Ramos LA, Ulic SE, Romano RM, Vishnevskiy YV, Berger RJF, Mitzel NW, Beckers H, Willner H, Tong S, Ge M, Della Védova CO. Chlorodifluoroacetyl Isocyanate, ClF2CC(O)NCO: Preparation and Structural and Spectroscopic Studies. J Phys Chem A 2012; 116:11586-95. [DOI: 10.1021/jp3096055] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Luis A. Ramos
- CEQUINOR (UNLP-CONICET), Departamento
de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República
Argentina
| | - Sonia E. Ulic
- CEQUINOR (UNLP-CONICET), Departamento
de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República
Argentina
| | - Rosana M. Romano
- CEQUINOR (UNLP-CONICET), Departamento
de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República
Argentina
| | - Yury V. Vishnevskiy
- Lehrstuhl für
Anorganische
Chemie und Strukturchemie, Universität Bielefeld, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Raphael J. F. Berger
- Lehrstuhl für
Anorganische
Chemie und Strukturchemie, Universität Bielefeld, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Norbert W. Mitzel
- Lehrstuhl für
Anorganische
Chemie und Strukturchemie, Universität Bielefeld, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Helmut Beckers
- Fachbereich C - Anorganische Chemie, Bergische Universität Wuppertal, 42097 Wuppertal,
Germany
| | - Helge Willner
- Fachbereich C - Anorganische Chemie, Bergische Universität Wuppertal, 42097 Wuppertal,
Germany
| | - Shengrui Tong
- State Key Laboratory
for Structural
Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Maofa Ge
- State Key Laboratory
for Structural
Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Carlos O. Della Védova
- CEQUINOR (UNLP-CONICET), Departamento
de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República
Argentina
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6
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Ramos LA, Zeng X, Ulic SE, Beckers H, Willner H, Della Védova CO. Chlorodifluoroacetyl Azide, ClF2CC(O)N3: Preparation, Properties, and Decomposition. J Org Chem 2012; 77:6456-62. [DOI: 10.1021/jo3009726] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Luis A. Ramos
- CEQUINOR (UNLP-CONICET), Departamento
de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, Argentina
| | - Xiaoqing Zeng
- Fachbereich
C - Anorganische Chemie, Bergische Universität Wuppertal, 42097 Wuppertal,
Germany
| | - Sonia E. Ulic
- CEQUINOR (UNLP-CONICET), Departamento
de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, Argentina
- Departamento de Ciencias Básicas, Universidad Nacional de Luján, Rutas 5 y 7 (6700),
Luján, Argentina
| | - Helmut Beckers
- Fachbereich
C - Anorganische Chemie, Bergische Universität Wuppertal, 42097 Wuppertal,
Germany
| | - Helge Willner
- Fachbereich
C - Anorganische Chemie, Bergische Universität Wuppertal, 42097 Wuppertal,
Germany
| | - Carlos O. Della Védova
- CEQUINOR (UNLP-CONICET), Departamento
de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, Argentina
- Laboratorio de Servicios a la Industria y al Sistema Científico (UNLP-CIC-CONICET), Buenos Aires, Argentina
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8
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Zeng X, Bernhardt E, Beckers H, Willner H. Synthesis and Characterization of the Phosphorus Triazides OP(N3)3 and SP(N3)3. Inorg Chem 2011; 50:11235-41. [DOI: 10.1021/ic201802x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Xiaoqing Zeng
- FB C − Anorganische Chemie, Bergische Universität Wuppertal, Gauss Strasse 20, D-42097 Wuppertal, Germany
| | - Eduard Bernhardt
- FB C − Anorganische Chemie, Bergische Universität Wuppertal, Gauss Strasse 20, D-42097 Wuppertal, Germany
| | - Helmut Beckers
- FB C − Anorganische Chemie, Bergische Universität Wuppertal, Gauss Strasse 20, D-42097 Wuppertal, Germany
| | - Helge Willner
- FB C − Anorganische Chemie, Bergische Universität Wuppertal, Gauss Strasse 20, D-42097 Wuppertal, Germany
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9
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Zeng X, Beckers H, Bernhardt E, Willner H. Synthesis and Characterization of Sulfuryl Diazide, O2S(N3)2. Inorg Chem 2011; 50:8679-84. [DOI: 10.1021/ic201294b] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Xiaoqing Zeng
- Bergische Universität Wuppertal, FB C − Anorganische Chemie, Gauss Strasse 20, D-42097 Wuppertal, Germany
| | - Helmut Beckers
- Bergische Universität Wuppertal, FB C − Anorganische Chemie, Gauss Strasse 20, D-42097 Wuppertal, Germany
| | - Eduard Bernhardt
- Bergische Universität Wuppertal, FB C − Anorganische Chemie, Gauss Strasse 20, D-42097 Wuppertal, Germany
| | - Helge Willner
- Bergische Universität Wuppertal, FB C − Anorganische Chemie, Gauss Strasse 20, D-42097 Wuppertal, Germany
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Boudon V, Doménech JL, Ramos A, Bermejo D, Willner H. High-resolution stimulated Raman spectroscopy and analysis of the ν 2, ν 5 and 2ν 6 bands of 34SF6. Mol Phys 2010. [DOI: 10.1080/00268970600722921] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- V. Boudon
- Laboratoire de Physique de l'Université de Bourgogne , CNRS UMR 5027, 9, Avenue Alain Savary, BP 47870, F-21078 Dijon Cedex, France
| | - J. L. Doménech
- Instituto de Estructura de la Materia CSIC , Serrano 123, E-28006 Madrid, Spain
| | - A. Ramos
- Instituto de Estructura de la Materia CSIC , Serrano 123, E-28006 Madrid, Spain
| | - D. Bermejo
- Instituto de Estructura de la Materia CSIC , Serrano 123, E-28006 Madrid, Spain
| | - H. Willner
- Fachbereich 9 – Anorganische Chemie, Bergische Universität Wuppertal , D-42097 Wuppertal, Germany
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11
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Ramos LA, Ulic SE, Romano RM, Erben MF, Lehmann CW, Bernhardt E, Beckers H, Willner H, Della Védova CO. Vibrational Spectra, Crystal Structures, Constitutional and Rotational Isomerism of FC(O)SCN and FC(O)NCS. Inorg Chem 2010; 49:11142-57. [DOI: 10.1021/ic101741e] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Luis A. Ramos
- CEQUINOR (UNLP-CONICET), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República Argentina
| | - Sonia E. Ulic
- CEQUINOR (UNLP-CONICET), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República Argentina
- Departamento de Ciencias Básicas, Universidad Nacional de Luján, Rutas 5 y 7, 6700 Luján, Argentina
| | - Rosana M. Romano
- CEQUINOR (UNLP-CONICET), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República Argentina
| | - Mauricio F. Erben
- CEQUINOR (UNLP-CONICET), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República Argentina
| | | | - Eduard Bernhardt
- Fachbereich C, Anorganische Chemie, Bergische Universität Wuppertal, 42097 Wuppertal, Germany
| | - Helmut Beckers
- Fachbereich C, Anorganische Chemie, Bergische Universität Wuppertal, 42097 Wuppertal, Germany
| | - Helge Willner
- Fachbereich C, Anorganische Chemie, Bergische Universität Wuppertal, 42097 Wuppertal, Germany
| | - Carlos O. Della Védova
- CEQUINOR (UNLP-CONICET), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, República Argentina
- Laboratorio de Servicios a la Industria y al Sistema Científico (UNLP-CIC-CONICET), Buenos Aires, República Argentina
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12
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Zeng X, Beckers H, Willner H, Berger RJF, Hayes SA, Mitzel NW. Structure and Conformational Properties of Azido(difluoro)phosphane, F
2
PN
3. Eur J Inorg Chem 2010. [DOI: 10.1002/ejic.201000882] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Xiaoqing Zeng
- Bergische Universität Wuppertal, FB C – Anorganische Chemie, Gauß‐Straße 20, 42097 Wuppertal, Germany, Fax: +49‐202‐439‐3053
| | - Helmut Beckers
- Bergische Universität Wuppertal, FB C – Anorganische Chemie, Gauß‐Straße 20, 42097 Wuppertal, Germany, Fax: +49‐202‐439‐3053
| | - Helge Willner
- Bergische Universität Wuppertal, FB C – Anorganische Chemie, Gauß‐Straße 20, 42097 Wuppertal, Germany, Fax: +49‐202‐439‐3053
| | - Raphael J. F. Berger
- Universität Bielefeld, Lehrstuhl für Anorganische Chemie und Strukturchemie, Universitätsstraße 15, 33615 Bielefeld, Germany
| | - Stuart A. Hayes
- Universität Bielefeld, Lehrstuhl für Anorganische Chemie und Strukturchemie, Universitätsstraße 15, 33615 Bielefeld, Germany
| | - Norbert W. Mitzel
- Universität Bielefeld, Lehrstuhl für Anorganische Chemie und Strukturchemie, Universitätsstraße 15, 33615 Bielefeld, Germany
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13
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Zeng X, Gerken M, Beckers H, Willner H. Synthesis and Characterization of Carbonyl Diazide, OC(N3)2. Inorg Chem 2010; 49:9694-9. [DOI: 10.1021/ic1015143] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xiaoqing Zeng
- Bergische Universität Wuppertal, FB C − Anorganische Chemie, Gauss Strasse 20, D-42097 Wuppertal, Germany
| | - Michael Gerken
- Bergische Universität Wuppertal, FB C − Anorganische Chemie, Gauss Strasse 20, D-42097 Wuppertal, Germany
- Department of Chemistry and Biochemistry, The University of Lethbridge, Lethbridge, Alberta T1K 3M4, Canada
| | - Helmut Beckers
- Bergische Universität Wuppertal, FB C − Anorganische Chemie, Gauss Strasse 20, D-42097 Wuppertal, Germany
| | - Helge Willner
- Bergische Universität Wuppertal, FB C − Anorganische Chemie, Gauss Strasse 20, D-42097 Wuppertal, Germany
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14
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Belova NV, Oberhammer H, Zeng X, Gerken M, Willner H, Berger RJF, Hayes SA, Mitzel NW. The keto/enol tautomerism in acetoacetyl fluoride: properties, spectroscopy, and gas-phase and crystal structures of the enol form. Phys Chem Chem Phys 2010; 12:11445-53. [PMID: 20683513 DOI: 10.1039/c002743j] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Tautomeric properties of acetoacetyl fluoride, CH(3)-C(O)-CH(2)-C(O)-F, were studied by IR (gas phase), Raman (liquid and solid), and NMR spectroscopy (neat liquid), gas electron diffraction (GED), X-ray crystallography, and quantum chemical calculations. The keto-enol tautomer possesses a much higher vapour pressure than the diketo form and therefore the keto-enol form strongly predominates in the gas phase. In the neat liquid state the thermally unstable compound tautomerizes at low temperatures slowly to yield the diketo form. Raman and NMR spectra show equilibrium with strong predominance of the diketo tautomer (>90%) in the liquid phase. Single crystals, grown at -90 °C from the gas phase, contain exclusively acetoacetyl fluoride in the keto-enol form and the molecules possess a planar skeleton with overall C(S) symmetry and with the O-H bond adjacent to the methyl group.
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Affiliation(s)
- Natalya V Belova
- Ivanovo State University of Chemistry and Technology, Engelsa av., 7, Ivanovo, 153460, Russia.
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15
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Torrico-Vallejos S, Erben MF, Boese R, Della Védova CO. Methoxycarbonyl trifluoromethyl disulfide, CH3OC(O)SSCF3: synthesis, structure and conformational properties. NEW J CHEM 2010. [DOI: 10.1039/b9nj00382g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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16
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Erben MF, Padró JM, Willner H, Della Védova CO. Conformational and Structural Determination of F2NC(O)F and F2NC(O)NCO. A Joint Experimental and Theoretical Study. J Phys Chem A 2009; 113:13029-35. [DOI: 10.1021/jp907827q] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mauricio F. Erben
- CEQUINOR (UNLP-CONICET, CCT La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC 962, La Plata (CP 1900), República Argentina, Fachbereich C-Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, 47097 Wuppertal, Germany, and Laboratorio de Servicios a la Industria y al Sistema Científico (LaSeISiC) (UNLP-CIC-CONICET), Camino Centenario e/505 y 508, (1903) Gonnet, República Argentina
| | - Juan M. Padró
- CEQUINOR (UNLP-CONICET, CCT La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC 962, La Plata (CP 1900), República Argentina, Fachbereich C-Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, 47097 Wuppertal, Germany, and Laboratorio de Servicios a la Industria y al Sistema Científico (LaSeISiC) (UNLP-CIC-CONICET), Camino Centenario e/505 y 508, (1903) Gonnet, República Argentina
| | - Helge Willner
- CEQUINOR (UNLP-CONICET, CCT La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC 962, La Plata (CP 1900), República Argentina, Fachbereich C-Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, 47097 Wuppertal, Germany, and Laboratorio de Servicios a la Industria y al Sistema Científico (LaSeISiC) (UNLP-CIC-CONICET), Camino Centenario e/505 y 508, (1903) Gonnet, República Argentina
| | - Carlos O. Della Védova
- CEQUINOR (UNLP-CONICET, CCT La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC 962, La Plata (CP 1900), República Argentina, Fachbereich C-Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, 47097 Wuppertal, Germany, and Laboratorio de Servicios a la Industria y al Sistema Científico (LaSeISiC) (UNLP-CIC-CONICET), Camino Centenario e/505 y 508, (1903) Gonnet, República Argentina
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Beckers H, Willner H, Grote D, Sander W, Geier J. Electron paramagnetic resonance spectrum of the FCO2 radical isolated in noble gas matrices. J Chem Phys 2008; 128:224301. [DOI: 10.1063/1.2933462] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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18
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Beckers H, Willner H, Grote D, Sander W. EPR and IR spectra of the FSO3 radical revisited: Strong vibronic interactions in the A22 electronic ground state. J Chem Phys 2008; 128:084501. [DOI: 10.1063/1.2831511] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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Kwabia Tchana F, Orphal J, Kleiner I, Rudolph HD, Willner H, Garcia P, Bouba O, Demaison J, Redlich B. Experimental and ab initio structure of BrN02. Mol Phys 2008. [DOI: 10.1080/00268970410001725828] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- F. Kwabia Tchana
- a Laboratoire de Photophysique Moléculaire , Bât. 350, 91405 , Orsay Cedex , France
- g Centre de Physique Atomique Moléculaire et Optique Quantique (CEPAMOQ) , Université de Douala , B.P. 8580 , Douala , Cameroon
| | - J. Orphal
- a Laboratoire de Photophysique Moléculaire , Bât. 350, 91405 , Orsay Cedex , France
| | - I. Kleiner
- a Laboratoire de Photophysique Moléculaire , Bât. 350, 91405 , Orsay Cedex , France
| | - H. D Rudolph
- b Fachbereich Chemie , Universität Ulm , 89069 , Ulm , Germany
| | - H. Willner
- c Fachbereich C – Anorganische Chemie , Bergische Universität Wuppertal , 42097 , Wuppertal , Germany
| | - P. Garcia
- c Fachbereich C – Anorganische Chemie , Bergische Universität Wuppertal , 42097 , Wuppertal , Germany
| | - O. Bouba
- d Faculté des Sciences , Université de Ngaoundéré , B.P. 454, Ngaoundéré , Cameroon
| | - J. Demaison
- e Laboratoire de Physique des Lasers, Atomes et Molécules, UMR CNRS 8523 , Université de Lille 1 , 59655, Villeneuve d'Ascq Cedex , France
| | - B. Redlich
- f FOM Institute for Plasma Physics , P.O. Box 1207, 3430 , BE , Nieuwegein , Netherlands
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Torrico Vallejos S, Erben MF, Willner H, Boese R, Della Védova CO. Preparation and Properties of Methoxycarbonylsulfenyl Isocyanate, CH3OC(O)SNCO. J Org Chem 2007; 72:9074-80. [DOI: 10.1021/jo701543g] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Sonia Torrico Vallejos
- CEQUINOR (CONICET-UNLP), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (B1900AJL), C.C. 962, La Plata, Buenos Aires, República Argentina, Laboratorio de Servicios a la Industria y al Sistema Científico (UNLP-CIC-CONICET) Camino Centenario, Gonnet, Buenos Aires, República Argentina, FB C, Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, D-42119 Wuppertal, Germany, and Institut für Anorganische Chemie, Universität Duisburg-Essen,
| | - Mauricio F. Erben
- CEQUINOR (CONICET-UNLP), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (B1900AJL), C.C. 962, La Plata, Buenos Aires, República Argentina, Laboratorio de Servicios a la Industria y al Sistema Científico (UNLP-CIC-CONICET) Camino Centenario, Gonnet, Buenos Aires, República Argentina, FB C, Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, D-42119 Wuppertal, Germany, and Institut für Anorganische Chemie, Universität Duisburg-Essen,
| | - Helge Willner
- CEQUINOR (CONICET-UNLP), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (B1900AJL), C.C. 962, La Plata, Buenos Aires, República Argentina, Laboratorio de Servicios a la Industria y al Sistema Científico (UNLP-CIC-CONICET) Camino Centenario, Gonnet, Buenos Aires, República Argentina, FB C, Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, D-42119 Wuppertal, Germany, and Institut für Anorganische Chemie, Universität Duisburg-Essen,
| | - Roland Boese
- CEQUINOR (CONICET-UNLP), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (B1900AJL), C.C. 962, La Plata, Buenos Aires, República Argentina, Laboratorio de Servicios a la Industria y al Sistema Científico (UNLP-CIC-CONICET) Camino Centenario, Gonnet, Buenos Aires, República Argentina, FB C, Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, D-42119 Wuppertal, Germany, and Institut für Anorganische Chemie, Universität Duisburg-Essen,
| | - Carlos O. Della Védova
- CEQUINOR (CONICET-UNLP), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (B1900AJL), C.C. 962, La Plata, Buenos Aires, República Argentina, Laboratorio de Servicios a la Industria y al Sistema Científico (UNLP-CIC-CONICET) Camino Centenario, Gonnet, Buenos Aires, República Argentina, FB C, Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, D-42119 Wuppertal, Germany, and Institut für Anorganische Chemie, Universität Duisburg-Essen,
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Erben MF, Boese R, Willner H, Della Védova CO. Chlorodifluorothioacetic Acid, CF2ClC(O)SH: Synthesis, Characterization, X-ray Structure and Conformational Properties. European J Org Chem 2007. [DOI: 10.1002/ejoc.200700349] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Bernhardt E, Finze M, Willner H, Lehmann CW, Aubke F. Salts of the Cobalt(I) Complexes [Co(CO)5]+ and [Co(CO)2(NO)2]+ and the Lewis Acid–Base Adduct [Co2(CO)7COB(CF3)3]. Chemistry 2006; 12:8276-83. [PMID: 16915593 DOI: 10.1002/chem.200600210] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The reaction of [Co(2)(CO)(8)] with (CF(3))(3)BCO in hexane leads to the Lewis acid-base adduct [Co(2)(CO)(7)CO--B(CF(3))(3)] in high yield. When the reaction is performed in anhydrous HF solution [Co(CO)(5)][(CF(3))(3)BF] is isolated. The product contains the first example of a homoleptic metal pentacarbonyl cation with 18 valence electrons and a trigonal-bipyramidal structure. Treatment of [Co(2)(CO)(8)] or [Co(CO)(3)NO] with NO(+) salts of weakly coordinating anions results in mixed crystals containing the [Co(CO)(5)](+)/[Co(CO)(2)(NO)(2)](+) ions or pure novel [Co(CO)(2)(NO)(2)](+) salts, respectively. This is a promising route to other new metal carbonyl nitrosyl cations or even homoleptic metal nitrosyl cations. All compounds were characterized by vibrational spectroscopy and by single-crystal X-ray diffraction.
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Affiliation(s)
- Eduard Bernhardt
- FB C Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, 42119 Wuppertal, Germany
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Erben MF, Della Védova CO, Willner H, Boese R. Synthesis, Structure and Conformational Properties of Fluoroformylchlorodifluoroacetyl Disulfide, FC(O)SSC(O)CF2Cl: Conformational Transferability in –C(O)SSC(O)– Compounds. Eur J Inorg Chem 2006. [DOI: 10.1002/ejic.200600604] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Lu N, Thrasher JS, von Ahsen S, Willner H, Hnyk D, Oberhammer H. Pentafluoronitrosulfane, SF5NO2. Inorg Chem 2006; 45:1783-8. [PMID: 16471994 DOI: 10.1021/ic0516212] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The synthesis of pentafluoronitrosulfane, SF5NO2, is accomplished either by reacting N(SF5)3 with NO2 or by the photolysis of a SF5Br/NO2 mixture using diazo lamps. The product is purified by treatment with CsF and repeated trap-to-trap condensation. The solid compound melts at -78 degrees C, and the extrapolated boiling point is 9 degrees C. SF5NO2 is characterized by 19F, 15N NMR, IR, Raman, and UV spectroscopy as well as by mass spectrometry. The molecular structure of SF5NO2 is determined by gas electron diffraction. The molecule possesses C2v symmetry with the NO2 group staggering the equatorial S-F bonds and an extremely long 1.903(7) Angstroms S-N bond. Calculated bond enthalpies depend strongly on the computational method: 159 (MP2/6-311G++(3df)) and 87 kJ mol(-1) (B3LYP/6-311++G(3df)). The experimental geometry and vibrational spectrum are reproduced reasonably well by quantum chemical calculations.
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Affiliation(s)
- Norman Lu
- Department of Chemistry, University of Alabama, Tuscaloosa, 35487, USA.
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Finze M, Bernhardt E, Willner H, Lehmann CW. Reactions of (CF3)3BCO with Amines and Phosphines. Inorg Chem 2005; 45:669-78. [PMID: 16411702 DOI: 10.1021/ic0515305] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reactions of tris(trifluoromethyl)borane carbonyl, (CF(3))(3)BCO, with ammonia yielded either a mixture of [NH(4)][(CF(3))(3)BC(O)NH(2)], [NH(4)][(CF(3))(3)BCN], and [NH(4)](2)[{(CF(3))(3)BC(O)}(2)NH] or neat [NH(4)](2)[{(CF(3))(3)BC(O)}(2)NH] depending on the reaction conditions. The salt K[(CF(3))(3)BC(O)NH(2)] was obtained as the sole product from the reaction of NH(3) with K[(CF(3))(3)BC(O)F]. A simple synthesis for cyanotris(trifluoromethyl)borates, M[(CF(3))(3)BCN], was developed by dehydration of M[(CF(3))(3)BC(O)NH(2)] (M = [NH(4)], K) using phosgene. In addition, syntheses of the tris(trifluoromethyl)boron species [(CF(3))(3)BC(O)NH(n)()Pr](-), [(CF(3))(3)BC(O)NMe(2)](-), and (CF(3))(3)BC(O)NMe(3), as well as of (CF(3))(3)BC(O)PMe(3), were performed. All species were characterized by multinuclear NMR spectroscopy. As far as neat substances resulted, IR and Raman spectra were recorded and their thermal behaviors were studied by differential scanning calorimetry. The interpretation of reaction pathways, structures, and vibrational spectra are supported by DFT calculations. The solid-state structure of K(2)[{(CF(3))(3)BC(O)}(2)NH].2MeCN was determined by single-crystal X-ray diffraction.
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Affiliation(s)
- Maik Finze
- FB C-Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, D-42097 Wuppertal, Germany.
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26
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Erben MF, Boese R, Della Védova CO, Oberhammer H, Willner H. Toward an Intimate Understanding of the Structural Properties and Conformational Preference of Oxoesters and Thioesters: Gas and Crystal Structure and Conformational Analysis of Dimethyl Monothiocarbonate, CH3OC(O)SCH3. J Org Chem 2005; 71:616-22. [PMID: 16408971 DOI: 10.1021/jo052026k] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[structure: see text] The molecular structure and conformational properties of dimethyl monothiocarbonate, CH3OC(O)SCH3, have been studied in the gas phase by gas electron diffraction (GED) and vibrational spectroscopy and in the solid state by X-ray crystallography. The experimental investigations were supplemented by quantum chemical calculations at the B3LYP/6-311++G(3df,2p) and MP2/6-311++G(2df,p) levels of approximation. The gaseous molecule exhibits only one conformation having Cs symmetry with synperiplanar orientation of both the C-S and the C-O single bonds relative to the C=O double bond. The following skeletal geometric parameters were derived from the GED analysis (r(hl) values with 3sigma uncertainties): C=O = 1.203(4) A, C(sp(2))-O = 1.335(5) A, C(sp(3))-O = 1.437(5) A, C(sp(2))-S = 1.763(5) A, and C(sp(3))-S = 1.803(5) A; O=C-O = 125.9(8) degrees , O=C-S = 125.7(7) degrees , O-C-S = 108.4(9) degrees , and C-O-C = 113.4(15) degrees . The structure of a single crystal, grown by a miniature zone-melting procedure, was determined by X-ray diffraction analysis at a low temperature. The crystalline solid [monoclinic, P2(1)/n, a = 12.6409(9) A, b = 4.1678(3) A, and c = 19.940(1) A, beta = 98.164(1) degrees ] exists exclusively as molecules in the synperiplanar conformation and with geometrical parameters that agree with those of the molecule in the gas phase. The results are discussed in terms of anomeric and mesomeric effects and in terms of a natural bond orbital analysis.
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Affiliation(s)
- Mauricio F Erben
- CEQUINOR (CONICET), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 115 C.C. 962, (B1900AJL) La Plata, Buenos Aires, Argentina
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Finze M, Bernhardt E, Willner H, Lehmann CW. Haloacyl Complexes of Boron, [(CF3)3BC(O)Hal]− (Hal=F, Cl, Br, I). Chemistry 2005; 11:6653-65. [PMID: 16130154 DOI: 10.1002/chem.200500038] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The haloacyltris(trifluoromethyl)borate anions [(CF3)3BC(O)Hal]- (Hal=F, Cl, Br, I) have been synthesized by reacting (CF3)3BCO with either MHal (M=K, Cs; Hal=F) in SO2 or MHal (M=[nBu4N]+, [Et4N]+, [Ph4P]+; Hal=Cl, Br, I) in dichloromethane. Metathesis reactions of the fluoroacyl complex with Me3SiHal (Hal=Cl, Br, I) led to the formation of its higher homologues. The thermal stabilities of the haloacyltris(trifluoromethyl)borates decrease from the fluorine to the iodine derivative. The chemical reactivities decrease in the same order as demonstrated by a series of selected reactions. The new [(CF3)3BC(O)Hal]- (Hal=F, Cl, Br) salts are used as starting materials in the syntheses of novel compounds that contain the (CF3)3B-C fragment. All borate anions [(CF3)3BC(O)Hal]- (Hal=F, Cl, Br, I) have been characterized by multinuclear NMR spectroscopy (11B, 13C, 17O, 19F) and vibrational spectroscopy. [PPh4][(CF3)3BC(O)Br] crystallizes in the monoclinic space group P2/c (no. 13) and the bond parameters are compared with those of (CF3)3BCO and K[(CF3)3BC(O)F]. The interpretation of the spectroscopic and structural data are supported by DFT calculations [B3LYP/6-311+G(d)].
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Affiliation(s)
- Maik Finze
- FB C-Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, 42097 Wuppertal, Germany.
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Erben MF, Della Védova CO, Willner H, Trautner F, Oberhammer H, Boese R. Fluoroformyl Trifluoroacetyl Disulfide, FC(O)SSC(O)CF3: Synthesis, Structure in Solid and Gaseous States, and Conformational Properties. Inorg Chem 2005; 44:7070-7. [PMID: 16180869 DOI: 10.1021/ic0506862] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Fluoroformyl trifluoroacetyl disulfide, FC(O)SSC(O)CF3, is prepared by quantitative reaction between FC(O)SCl and CF(3)C(O)SH. The conformational properties and geometric structure of the gaseous molecule have been studied by vibrational spectroscopy (IR(gas), Raman(liquid), IR(matrix)), gas electron diffraction (GED), and quantum chemical calculations (B3LYP and MP2 methods). The disulfide bond length derived from the GED analysis amounts 2.023(3) Angstroms, and the dihedral angle around this bond, phi(CS-SC), is 77.7(21) degrees, being the smallest dihedral angle measured for noncyclic disulfides in the gas phase. The compound exhibits a conformational equilibrium at room temperature having the most stable form C(1) symmetry with a synperiplanar (sp-sp) orientation of both carbonyl groups with respect to the disulfide bond. A second form was observed in IR spectra of the Ar matrix isolated compound at cryogenic temperatures, corresponding to a conformer that possess the carbonyl bond of the FC(O) moiety in antiperiplanar position with respect to the S-S single bond (ap-sp). A DeltaH degrees = - = 1.34(11) kcal/mol has been determined by IR(matrix) spectroscopy. The structure of single crystal of FC(O)SSC(O)CF3 was determinate by X-ray diffraction analysis at low temperature using a miniature zone melting procedure. The crystalline solid (monoclinic, P2(1)/n, a = 5.240(4)Angstroms, b = 23.319(17)Angstroms, c = 6.196(4)Angstroms, beta = 113.14(3) degrees) consists exclusively of the (sp-sp) conformation. The geometrical parameters agree with those obtained for the molecule in the gas phase.
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Affiliation(s)
- Mauricio F Erben
- CEQUINOR (CONICET-UNLP), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Buenos Aires, República of Argentina
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Finze M, Bernhardt E, Willner H, Lehmann CW. Cyano- and Isocyanotris(trifluoromethyl)borates: Syntheses, Spectroscopic Properties, and Solid State Structures of K[(CF3)3BCN] and K[(CF3)3BNC]. J Am Chem Soc 2005; 127:10712-22. [PMID: 16045360 DOI: 10.1021/ja0516357] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A two step synthesis to the isocyanotris(trifluoromethyl)borate anion, [(CF3)3BNC]-, and its isomerization to the cyanotris(trifluoromethyl)borate anion, [(CF3)3BCN]-, at temperatures above 150 degrees C are presented. In the first step (CF3)3BNCH was obtained by reacting (CF3)3BCO with hydrogen cyanide followed by deprotonation of the HCN adduct with Li[N(SiMe3)2] in toluene. The thermal behavior of K[(CF3)3BNC] and K[(CF3)3BCN] were investigated by differential scanning calorimetry (DSC), and K[BF4] was identified as a major solid decomposition product. The enthalpy of the isocyanide-cyanide rearrangement, deltaH(iso) = -35 +/- 4 kJ mol(-1), was obtained from DSC measurements, and the activation energy, E(a) = 180 +/- 20 kJ mol(-1), from kinetic measurements. The isomerization was modeled as an intramolecular reaction employing DFT calculations at the B3LYP/6-311+G(d) level of theory yielding a reaction enthalpy of deltaH(iso) = -36.1 kJ mol(-1) and an activation energy of E(a) = 155.7 kJ mol(-1). The solid-state structures of K[(CF3)3BNC] and K[(CF3)3BCN] were determined by single-crystal X-ray diffraction. Both salts are isostructural and crystallize in the orthorhombic space group Pnma (no. 62). In the crystals the borate anions possess C(s) symmetry, while for the energetic minimum C3 symmetry is predicted by DFT calculations. The borate anions have been characterized by IR and Raman spectroscopy as well as by NMR spectroscopy. The assignment of the IR and Raman bands is supported by their calculated wavenumbers and intensities. The spectroscopic and structural properties of both borate anions are compared to the properties of the isoelectronic borane carbonyl (CF3)3BCO and the [B(CF3)4]- anion as well as to those of other related species.
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Affiliation(s)
- Maik Finze
- FBC - Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, D-42097 Wuppertal, Germany.
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García P, Willner H, Paci MB, Argüello GA, Berends T. Bis(trifluoromethyl)dicarbonate, CF3OC(O)OC(O)OCF3. J Fluor Chem 2005. [DOI: 10.1016/j.jfluchem.2005.05.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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García P, Pernice H, Willner H, Oberhammer H, Argüello GA. Properties of Chloroformyl Peroxynitrate, ClC(O)OONO2. Inorg Chem 2005; 44:4415-20. [PMID: 15934773 DOI: 10.1021/ic050229l] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The synthesis of ClC(O)OONO(2) is accomplished by photolysis of a mixture of Cl(2), NO(2), and CO in large excess of O(2) at about -70 degrees C. The product is isolated after repeated trap-to-trap condensation. The solid compound melts at -84 degrees C, and the extrapolated boiling point is 80 degrees C. ClC(O)OONO(2) is characterized by IR, Raman, (13)C NMR, and UV spectroscopy. According to the IR matrix spectra, the compound exists at room temperature only as a single conformer. The molecular structure of ClC(O)OONO(2) is determined by gas electron diffraction. The molecule possesses a gauche structure with a dihedral angle of phi(COON) = 86.7(19) degrees , and the C=O bond is oriented syn with respect to the O-O bond. The short O-O bond (1.418(6) A) and the long N-O bond (1.511(8) A) are consistent with the facile dissociation of ClC(O)OONO(2) into the radicals ClC(O)OO and NO(2). The experimental geometry of ClC(O)OONO(2) is reproduced reasonably well by B3LYP/6-311+G(2df) calculations, whereas the MP2 approximation predicts the N-O bond considerably too long and the dihedral angle too small.
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Affiliation(s)
- Plácido García
- FB C, Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, D-42097 Wuppertal, Germany
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García P, Willner H, Oberhammer H, Francisco JS. The matrix-isolated molecular complexes CO/XF (X=Cl,Br,I) and the molecular structure of FC(O)Br. J Chem Phys 2004; 121:11900-6. [PMID: 15634151 DOI: 10.1063/1.1814634] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
FC(O)Br has been synthesized, and its IR spectrum in the gas phase and isolated in an Ar matrix, as well as, its Raman spectrum in the solid state at -196 degrees C has been analyzed. Its molecular structure has been determined and its UV has been measured. FC(O)Br and FC(O)Cl has been photodissociated in an argon matrix at 17 K with a 193 nm laser. The photolysis produces CO and XF which recombine to form CO/XF complexes. The formation of complexes are followed by the shift of the normal vibration modes with respect to CO and XF isolated in argon matrix. In the case of FC(O)Br, three isomers are identified, OC...BrF, OC...FBr, and CO...BrF, whereas for FC(O)Cl only one isomer is observed, OC...ClF. High level quantum chemical calculations are used to help the assignment of the different isomers.
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Affiliation(s)
- Plácido García
- FB C, Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, D-42097 Wuppertal, Germany
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Mayer F, Oberhammer H, Berkei M, Pernice H, Willner H, Bierbrauer K, Paci MB, Argüello GA. Structural and conformational properties of fluoroformic acid anhydride, FC(O)OC(O)F. Inorg Chem 2004; 43:8162-8. [PMID: 15578857 DOI: 10.1021/ic049210t] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The conformational properties and geometric structures of fluoroformic acid anhydride, FC(O)OC(O)F, have been studied by vibrational spectroscopy, gas electron diffraction (GED), single-crystal X-ray diffraction, and quantum chemical calculations (HF, MP2, and B3LYP methods with 6-31G* and B3LYP/6-311+G* basis sets). Satellite bands in the IR matrix spectra, which increase in intensity when the matrix gas mixture is heated prior to deposition as a matrix, indicate the presence of two conformers at room temperature. According to the electron diffraction analysis, the prevailing conformer is of C(2) symmetry with both C=O bonds synperiplanar with respect to the opposite C-O bond ([sp, sp] conformer). The minor conformer [15(5)% from IR matrix and 6(11)% from GED] is predicted by quantum chemical calculations to possess an [sp, ac] structure. FC(O)OC(O)F crystallizes in the orthorhombic system in the space group P2(1)2(1)2(1) with a = 6.527(1) angstroms, b = 7.027(1) angstroms, and c = 16.191(1) angstroms and four formula units per unit cell. In the crystal, only the [sp, sp] conformer is present, and the structural parameters are very similar to those determined by GED.
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Affiliation(s)
- Florian Mayer
- Institut für Physikalische und Theoretische Chemie, Universität Tübingen, D-72076 Tübingen, Germany
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von Ahsen S, Willner H, Francisco JS. Thermal decomposition of peroxy acetyl nitrate CH3C(O)OONO2. J Chem Phys 2004; 121:2048-57. [PMID: 15260758 DOI: 10.1063/1.1767813] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The thermal decomposition of peroxy acetyl nitrate (PAN) is investigated by low pressure flash thermolysis of PAN highly diluted in noble gases and subsequent isolation of the products in noble gas matrices at low temperatures and by density functional computations. The IR spectroscopically observed formation of CH3C(O)OO and H2CCO (ketene) besides NO2, CO2, and HOO implies a unimolecular decay pathway for the thermal decomposition of PAN. The major decomposition reaction of PAN is bond fission of the O-N single bond yielding the peroxy radical. The O-O bond fission pathway is a minor route. In the latter case the primary reaction products undergo secondary reactions whose products are spectroscopically identified. No evidence for rearrangement processes as the formation of methyl nitrate is observed. A detailed mapping of the reaction pathways for primary and secondary reactions using quantum chemical calculations is in good agreement with the experiment and predicts homolytic O-N and O-O bond fissions within the PAN molecule as the lowest energetic primary processes. In addition, the first IR spectroscopic characterization of two rotameric forms for the radical CH3C(O)OO is given.
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Affiliation(s)
- Stefan von Ahsen
- FB C/Anorganische Chemie, Bergische Universität Wuppertal, 42097, Germany
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35
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Ulic SE, von Ahsen S, Willner H. Photoisomerization of Matrix-Isolated Bis(trifluoromethyl) Sulfoxide: Formation of the Sulfenic Ester CF3SOCF3. Inorg Chem 2004; 43:5268-74. [PMID: 15310204 DOI: 10.1021/ic049800r] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Bis(trifluoromethyl) sulfoxide, CF(3)S(O)CF(3), isolated in noble gas matrixes at low temperatures, isomerizes upon UV irradiation into the sulfenic ester CF(3)SOCF(3). The new species is characterized spectroscopically, and the vibrational assignment is supported by (18)O isotopic labeling experiments and by DFT calculations. The calculated structural parameters of CF(3)SOCF(3) are compared with the calculated and experimental data of the related compounds CF(3)SSCF(3) and CF(3)OOCF(3). In addition, the computed enthalpy differences between the sulfoxide R(2)S=O and sulfenate RSOR structures for R = H, F, CH(3), and CF(3) are included.
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Affiliation(s)
- S E Ulic
- CEQUINOR, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, 1900 La Plata, Republic of Argentina.
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Erben MF, Della Védova CO, Willner H. N,N-Difluoro-O-trifluoromethyl-hydroxylamine, CF3ONF2: conformation and vibrational analysis studied by experimental and theoretical methods. J Mol Struct 2004. [DOI: 10.1016/j.molstruc.2004.01.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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37
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Erben MF, Della Védova CO, Boese R, Willner H, Oberhammer H. Trifluoromethyl Chloroformate, ClC(O)OCF3: Structure, Conformation, and Vibrational Analysis Studied by Experimental and Theoretical Methods. J Phys Chem A 2003. [DOI: 10.1021/jp036966p] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mauricio F. Erben
- CEQUINOR (CONICET-UNLP), Departamento de Quimica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (1900) La Plata, República Argentina, Laboratorio de Servicios a la Industria y al Sistema Científico (UNLP-CIC-CONICET), Departamento de Quimica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (1900) La Plata, República Argentina, Institut für Anorganische Chemie, Universität GH Essen, Universitätsstr. 5-7, D-45117 Essen, Germany, Fakultät 4,
| | - Carlos O. Della Védova
- CEQUINOR (CONICET-UNLP), Departamento de Quimica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (1900) La Plata, República Argentina, Laboratorio de Servicios a la Industria y al Sistema Científico (UNLP-CIC-CONICET), Departamento de Quimica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (1900) La Plata, República Argentina, Institut für Anorganische Chemie, Universität GH Essen, Universitätsstr. 5-7, D-45117 Essen, Germany, Fakultät 4,
| | - Roland Boese
- CEQUINOR (CONICET-UNLP), Departamento de Quimica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (1900) La Plata, República Argentina, Laboratorio de Servicios a la Industria y al Sistema Científico (UNLP-CIC-CONICET), Departamento de Quimica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (1900) La Plata, República Argentina, Institut für Anorganische Chemie, Universität GH Essen, Universitätsstr. 5-7, D-45117 Essen, Germany, Fakultät 4,
| | - Helge Willner
- CEQUINOR (CONICET-UNLP), Departamento de Quimica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (1900) La Plata, República Argentina, Laboratorio de Servicios a la Industria y al Sistema Científico (UNLP-CIC-CONICET), Departamento de Quimica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (1900) La Plata, República Argentina, Institut für Anorganische Chemie, Universität GH Essen, Universitätsstr. 5-7, D-45117 Essen, Germany, Fakultät 4,
| | - Heinz Oberhammer
- CEQUINOR (CONICET-UNLP), Departamento de Quimica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (1900) La Plata, República Argentina, Laboratorio de Servicios a la Industria y al Sistema Científico (UNLP-CIC-CONICET), Departamento de Quimica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (1900) La Plata, República Argentina, Institut für Anorganische Chemie, Universität GH Essen, Universitätsstr. 5-7, D-45117 Essen, Germany, Fakultät 4,
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Finze M, Bernhardt E, Zähres M, Willner H. Rearrangement Reactions of the Transient Lewis Acids (CF3)3B and (CF3)3BCF2: An Experimental and Theoretical Study. Inorg Chem 2003; 43:490-505. [PMID: 14731011 DOI: 10.1021/ic0350640] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Short-lived (CF(3))(3)B and (CF(3))(3)BCF(2) are generated as intermediates by thermal dissociation of (CF(3))(3)BCO and F(-) abstraction from the weak coordinating anion [B(CF(3))(4)](-), respectively. Both Lewis acids cannot be detected because of their instability with respect to rearrangement reactions at the B-C-F moiety. A cascade of 1,2-fluorine shifts to boron followed by perfluoroalkyl group migrations and also difluorocarbene transfer reactions occur. In the gas phase, (CF(3))(3)B rearranges to a mixture of linear perfluoroalkyldifluoroboranes C(n)()F(2)(n)()(+1)BF(2) (n = 2-7), while the respective reactions of (CF(3))(3)BCF(2) result in a mixture of linear (n = 2-4) and branched monoperfluoroalkyldifluoroboranes, e.g., (C(2)F(5))(CF(3))FCBF(2). For comparison, the reactions of [CF(3)BF(3)](-) and [C(2)F(5)BF(3)](-) with AsF(5) are studied, and the products in the case of [CF(3)BF(3)](-) are BF(3) and C(2)F(5)BF(2) whereas in the case of [C(2)F(5)BF(3)](-), C(2)F(5)BF(2) is the sole product. In contrast to reports in the literature, it is found that CF(3)BF(2) is too unstable at room temperature to be detected. The decomposition of (CF(3))(3)BCO in anhydrous HF leads to a mixture of the new conjugate Brønsted-Lewis acids [H(2)F][(CF(3))(3)BF] and [H(2)F][C(2)F(5)BF(3)]. All reactions are modeled by density functional calculations. The energy barriers of the transition states are low in agreement with the experimental results that (CF(3))(3)B and (CF(3))(3)BCF(2) are short-lived intermediates. Since CF(2) complexes are key intermediates in the rearrangement reactions of (CF(3))(3)B and (CF(3))(3)BCF(2), CF(2) affinities of some perfluoroalkylfluoroboranes are presented. CF(2) affinities are compared to CO and F(-) affinities of selected boranes showing a trend in Lewis acidity, and its influence on the stability of the complexes is discussed. Fluoride ion affinities are calculated for a variety of different fluoroboranes, including perfluorocarboranes, and compared to those of the title compounds.
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Affiliation(s)
- Maik Finze
- Fakultät 4, Anorganische Chemie, Universität Duisburg-Essen, Lotharstrasse 1, D-47048 Duisburg, Germany
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Erben MF, Della Védova CO, Boese R, Willner H, Leibold C, Oberhammer H. Trifluoromethyl Chlorosulfonate, CF3OSO2Cl: Gas Phase and Crystal Structure, Conformation and Vibrational Analysis Studied by Experimental and Theoretical Methods. Inorg Chem 2003; 42:7297-303. [PMID: 14577800 DOI: 10.1021/ic034531a] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The geometric structure and conformational properties of trifluoromethyl chlorosulfonate (chlorosulfuric acid trifluoromethyl ester), CF(3)OSO(2)Cl, have been determined by X-ray crystallography, gas electron diffraction (GED), and vibrational spectroscopy (IR(gas), IR(matrix), and Raman(liquid)). These experimental investigations were supplemented by quantum chemical calculations (B3LYP with 6-311G* and 6-311+G(3df) basis sets). All experimental methods result in a single conformer with gauche orientation of the CF(3) group relative to the S[bond]Cl. The dihedral angle delta(COSCl) is determined to be 91.7(3) degrees in the crystal and 94(3) degrees in the gas phase. This dihedral angle corresponds to a near-eclipsed orientation of the O[bond]C relative to one of the S[double bond]O bonds (delta(CO[bond]SO) = -23.0(3) degrees and -21(3) degrees in the crystal and gas phase, respectively).
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Affiliation(s)
- Mauricio F Erben
- CEQUINOR (CONICET-UNLP), Departamento de Quimica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (1900) La Plata, República Argentina
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40
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Trautner F, Gholivand K, García P, Willner H, Erben MF, Della Védova CO, Oberhammer H. Perfluoromethyl fluorocarbonyl peroxide, CF3OOC(O)F: structure, conformations, and vibrational spectra studied by experimental and theoretical methods. Inorg Chem 2003; 42:3079-85. [PMID: 12716204 DOI: 10.1021/ic0262583] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The conformational properties and the geometric structure of perfluoromethyl fluorocarbonyl peroxide, CF(3)OOC(O)F, have been studied by matrix IR spectroscopy, gas electron diffraction, and quantum chemical calculations (HF, B3LYP, and MP2 methods with 6-311G* basis sets). Matrix IR spectra imply a mixture of syn and anti conformers (orientation of the C=O bond relative to the O-O bond) with DeltaH degrees = H(anti) degrees - H(syn) degrees = 2.16(22) kcal/mol. At room temperature, the contribution of the anti rotamer is about 3.0%. The O-O bond (1.422(15) A) is within the experimental uncertainties equal to those in related symmetrically substituted peroxides CF(3)OOCF(3) and FC(O)OOC(O)F (1.419(20) and 1.419(9) A, respectively), and the dihedral angle delta(COOC) (111(5) degrees ) is intermediate between the values in these two compounds (123(4) degrees and 83.5(14) degrees, respectively).
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Affiliation(s)
- Frank Trautner
- Institut für Physikalische und Theoretische Chemie, Universität Tübingen, D-72076 Tübingen, Germany
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41
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Burgos Paci MA, García P, Malanca FE, Argüello GA, Willner H. Synthesis and characterization of trifluoromethyl fluoroformyl peroxycarbonate, CF3OC(O)OOC(O)F. Inorg Chem 2003; 42:2131-5. [PMID: 12639151 DOI: 10.1021/ic0261528] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis of CF(3)OC(O)OOC(O)F is accomplished by the photolysis of a mixture of (CF(3)CO)(2)O, FC(O)C(O)F, CO, and O(2) at -15 degrees C using a low-pressure mercury lamp. The new peroxide is obtained in pure form in low yield after repeated trap-to-trap condensation and is characterized by NMR, IR, Raman, and UV spectroscopy. Geometrical parameters were studied by ab initio methods [B3LYP/6-311+G(d)]. At room temperature, CF(3)OC(O)OOC(O)F is stable for many days in the liquid or gaseous state. The melting point is -87 degrees C, and the boiling point is extrapolated to 45 degrees C from the vapor pressure curve log p = 8.384 - 1715/T (p/mbar, T/K). A possible mechanism for the formation of CF(3)OC(O)OOC(O)F is discussed, and its properties are compared with those of related compounds.
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Affiliation(s)
- Maximiliano A Burgos Paci
- INFIQC, Departamento de Físico Química, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina
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42
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Zelinger Z, Dréan P, Walters A, Moreno JRA, Bogey M, Pernice H, von Ahsen S, Willner H, Breidung J, Thiel W, Bürger H. Gas-phase detection of the FCO2 radical by millimeter wave and high resolution infrared spectroscopy assisted by ab initio calculations. J Chem Phys 2003. [DOI: 10.1063/1.1528607] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Abstract
Low pressure flash thermolysis of different precursor molecules containing-ClO, -ClO3 or -OClO3 yield, when highly diluted in Ne or O2 and subsequent quenching of the products in a matrix at 5 or 15 K, ClOx (x = 1, 3, 4) radicals, respectively. If Ne or O2 gas is directed over solid ClO2 at -120 degrees C and the resulting gas mixtures are immediately deposited as a matrix, a high fraction of (OClO)2 is trapped. This enables recording of IR and UV spectra of weakly bonded (OClO)2 dimers and detailed studying of their photochemistry. For Ne or O2 matrix isolated ClO radicals the vibrational wavenumbers and electronic transitions are only slightly affected compared with the gas phase. In this study strong evidence is found for long lived ClO in the electronically excited 2 [symbol: see text] 1/2 state. A comprehensive IR study of Ne matrix isolated ClO3 (fundamentals at 1081, 905, 567, 476 cm-1) yield i) a reliable force field; ii) a OClO bond angle of alpha e = 113.8 +/- 1 degrees and iii) a ClO bond length of 148.5 +/- 2 pm in agreement with predicted data from quantum chemical calculations. The UV/Vis spectrum of ClO3 isolated in a Ne matrix (lambda max at 32,100 and 23,150 cm-1) agrees well with the photoelectron spectrum of ClO3- and theoretical predictions. The origin of the structured high energy absorption is at 22,696 cm-1 and three fundamentals (794, 498, 280 cm-1) are detected in the C2E state. By photolysis of ClO3 with visible light the complex ClO.O2 with ClO in the 2 [symbol: see text] 1/2 state is formed. In an extended spectroscopic study of the elusive ClO4 radical, isolated in a Ne or O2 matrix, three additional IR bands, a complete UV spectrum and a strong interaction with O2 are found. This leads to the conclusion that ClO4 exhibits C2v or Cs symmetry with a shallow potential minimum and forms with O2 the previously unknown peroxy radical O3ClO-O2. All these results are discussed in the context of recent developments in the chemistry and spectroscopy of the important and interesting ClOx (x = 1-4) family of radicals.
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Affiliation(s)
- Rodion Kopitzky
- Fakultät 4, Anorganische Chemie Gerhard-Mercator Universität Duisburg, Lotharstrasse 1 47048 Duisburg, Germany
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Kopitzky R, Willner H, Hermann A, Oberhammer H. Bis(trifluoroacetyl) peroxide, CF(3)C(O)OOC(O)CF(3). Inorg Chem 2001; 40:2693-8. [PMID: 11375681 DOI: 10.1021/ic0014639] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Pure, highly explosive CF(3)C(O)OOC(O)CF(3) is prepared for the first time by low-temperature reaction between CF(3)C(O)Cl and Na(2)O(2). At room temperature CF(3)C(O)OOC(O)CF(3) is stable for days in the liquid or gaseous state. The melting point is -37.5 degrees C, and the boiling point is extrapolated to 44 degrees C from the vapor pressure curve log p = -1875/T + 8.92 (p/mbar, T/K). Above room temperature the first-order unimolecular decay into C(2)F(6) + CO(2) occurs with an activation energy of 129 kJ mol(-1). CF(3)C(O)OOC(O)CF(3) is a clean source for CF(3) radicals as demonstrated by matrix-isolation experiments. The pure compound is characterized by NMR, vibrational, and UV spectroscopy. The geometric structure is determined by gas electron diffraction and quantum chemical calculations (HF, B3PW91, B3LYP, and MP2 with 6-31G basis sets). The molecule possesses syn-syn conformation (both C=O bonds synperiplanar to the O-O bond) with O-O = 1.426(10) A and dihedral angle phi(C-O-O-C) = 86.5(32) degrees. The density functional calculations reproduce the experimental structure very well.
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Affiliation(s)
- R Kopitzky
- Institut für Physikalische und Theoretische Chemie, Universität Tübingen, Auf der Morgenstelle 8, D-72076 Tübingen, Germany
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46
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Hermann A, Trautner F, Gholivand K, von Ahsen S, Varetti EL, Della Vedova CO, Willner H, Oberhammer H. Structures and conformations of trifluoromethyl fluoroformate and perfluorodimethyl carbonate. Inorg Chem 2001; 40:3979-85. [PMID: 11466057 DOI: 10.1021/ic010066a] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The conformational properties and geometric structures of trifluoromethyl fluoroformate, CF(3)OC(O)F (1), and perfluorodimethyl carbonate, (CF(3)O)(2)CO (2), have been studied by matrix IR spectroscopy, gas electron diffraction (GED), and quantum chemical calculations (MP2 and B3LYP with 6-311G basis sets). In both compounds the synperiplanar orientation of the O-CF(3) groups relative to the C=O double bond is preferred. If heated Ar/1 and Ar/2 mixtures are deposited as a matrix at 14 K, new bands appear in the matrix IR spectra which are assigned to the anti form of 1 and to the syn/anti form of 2. At room temperature the contribution of the anti rotamer of 1 is 4% (DeltaH degrees = H degrees (anti) - H degrees (syn) = 1.97(5) kcal/mol), and the contribution of the syn/anti conformer of 2 is estimated to be less than 1%. These high-energy conformers are not observed in the GED experiment. The quantum chemical calculations reproduce the structural and conformational properties of both compounds satisfactorily.
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Affiliation(s)
- A Hermann
- Institut für Physikalische und Theoretische Chemie, Universität Tübingen, D-72076 Tübingen, Germany
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Argüello GA, Willner H. IR and UV Absorption Spectrum of the Trifluoromethoxy Radical, CF3O·, Isolated in Rare Gas Matrices. J Phys Chem A 2001. [DOI: 10.1021/jp002960d] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gustavo A. Argüello
- FB 6-Anorganische Chemie, Gerhard-Mercator-Universität Duisburg, Lotharstrasse 1, D-47048 Duisburg, Germany
| | - Helge Willner
- FB 6-Anorganische Chemie, Gerhard-Mercator-Universität Duisburg, Lotharstrasse 1, D-47048 Duisburg, Germany
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Sander S, Pernice H, Willner H. IR and UV spectra of the matrix-isolated peroxy radicals CF3OO, trans-FC(O)OO, and cis-FC(O)OO. Chemistry 2000; 6:3645-53. [PMID: 11072830 DOI: 10.1002/1521-3765(20001002)6:19<3645::aid-chem3645>3.0.co;2-#] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The peroxy radicals CF3OO and FC(O)OO are prepared in high yields by vacuum flash pyrolysis of ROONO2 or ROOOR (R=CF3, FC(O)), highly diluted in inert gases, and subsequent isolation in inert-gas matrices by quenching the product mixtures at low temperatures. The IR spectrum of FC(O)OO was observed for the first time and eight fundamentals as well as several combinations were measured and assigned for both cis and trans rotamers of FC(O)OO. Discrepancies in an earlier assignment of the fundamentals of CF3OO have been eliminated and its IR spectrum is reported fully. The matrix UV spectra of both peroxy radicals (X2A"--> 2(2)A" transition) are in agreement with the gas-phase spectra; however, there are differences in the absorption cross-sections, for which possible reasons are discussed. The X2A"--> 1(2)A' transitions in the near IR region are too weak to be detected with our instrumentation.
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Affiliation(s)
- S Sander
- FB6-Anorganische Chemie, Gerhard-Mercator-Unviersitat Duisburg, Germany
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Sander S, Willner H, Khriachtchev L, Pettersson M, Räsänen M, Varetti EL. Vibrational Spectra of cis and trans Oxalyl Fluoride and Their Site-Selective IR-Induced Rotamerization in an Argon Matrix. JOURNAL OF MOLECULAR SPECTROSCOPY 2000; 203:145-150. [PMID: 10930342 DOI: 10.1006/jmsp.2000.8164] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A cis/trans equilibrium mixture of matrix-isolated oxalyl fluoride was irradiated with a narrowband tunable IR source in the 2nu (CO) spectral region (3680-3710 cm(-1)). Rotamerization of cis into trans and vice versa was achieved (even site selective) by selective IR pumping. The experiments strongly aided a detailed IR analysis of both rotamers. For a complete vibrational analysis, low-temperature Raman measurements were also performed. With the exception of the torsional vibration of cis oxalyl fluoride, all the fundamentals of both rotamers have been observed. Copyright 2000 Academic Press.
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Affiliation(s)
- S Sander
- Anorganische Chemie der Universität, Lotharstraße 1, Duisburg, D-47048, Germany
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Argüello GA, Willner H, Malanca FE. Reaction of CF3 radicals with CO and O2. Isolation of bis(trifluoromethyl)peroxydicarbonate, CF3OC(O)OOC(O)OCF3, and identification of bis(trifluoromethyl)trioxydicarbonate, CF3OC(O)OOOC(O)OCF3. Inorg Chem 2000; 39:1195-9. [PMID: 12526410 DOI: 10.1021/ic991265l] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis of CF3OC(O)OOCF3, CF3OC(O)OOC(O)OCF3, and CF3OC(O)OOOC(O)OCF3 is accomplished by the photolysis of a mixture of (CF3CO)2O, CO, and O2. Pure CF3OC(O)OOCF3 and CF3OC(O)OOC(O)OCF3 are isolated after thermal decomposition of CF3OC(O)OOOC(O)OCF3 and repeated trap-to-trap condensation. Additional spectroscopic data of known CF3OC(O)OOCF3 are obtained by recording NMR, IR, Raman, and UV spectra: At room temperature CF3OC(O)OOC(O)OCF3 is stable for days in the liquid or gaseous state. The melting point is -38 degrees C, and the boiling point is extrapolated to 73 degrees C from the vapor pressure curve log p = 8.657-1958/T (p/mbar, T/K). The new compound is characterized by molecular mass determination and by NMR, vibrational, and UV spectroscopy. The new trioxide CF3OC(O)OOOC(O)OCF3 cannot be separated from CF3-OC(O)OOC(O)OCF3 by distillation due to their similar boiling points. CF3OC(O)OOOC(O)OCF3 decomposes at room temperature within hours into a mixture of CF3OC(O)OOC(O)OCF3, CF3OC(O)OOCF3, CO2, and O2. Its characterization is discussed along with a possible mechanism for formation and decomposition reactions.
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Affiliation(s)
- G A Argüello
- Universität GH Duisburg, Lotharstrasse 1, D-47048 Duisburg, Germany
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