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Ghabi A, Slama T, Hedhli A, Boubaker T, Guillemin JC. Primary α-Phosphino- and α-Arseno-Nitriles, Analogues of α-Aminonitriles. Inorg Chem 2024. [PMID: 38818931 DOI: 10.1021/acs.inorgchem.4c01307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2024]
Abstract
More than 170 years after the synthesis of α-aminonitriles by the reaction of Strecker, α-phosphinonitriles, and α-arsenonitriles have been prepared and characterized by NMR and IR spectroscopy. For the simplest derivatives, the reaction was carried out by reaction of cyanomethyltributylstannane with phosphorus or arsenic trichloride, followed by a chemoselective reduction of the dichlorophosphine and dichloroarsine formed to the corresponding primary phosphine and arsine. The phosphinoacetonitrile can be stored at -80 °C for months in its pure state, but arsenoacetonitrile decomposes at this temperature. Chiral compounds can be synthesized from C-substituted cyano-1-alkyltributylstannanes. In 1H NMR spectroscopy, these chiral phosphines and arsines display diastereotopic protons for the PH2 and AsH2 groups, a property never observed for the NH2 group of α-aminonitriles. This work paves the way for further studies on the chemistry of these compounds, including a comparative chemistry of these phosphorus and arsenic derivatives with the well-known α-aminonitriles.
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Affiliation(s)
- Amira Ghabi
- Univ Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR - UMR6226, F-35000 Rennes, France
- Université de Monastir, Avenue Taher Hadded B.P 56, Monastir 5000, Tunisie
| | - Takwa Slama
- Univ Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR - UMR6226, F-35000 Rennes, France
- Université de Monastir, Avenue Taher Hadded B.P 56, Monastir 5000, Tunisie
| | - Amel Hedhli
- Univ Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR - UMR6226, F-35000 Rennes, France
- Université de Monastir, Avenue Taher Hadded B.P 56, Monastir 5000, Tunisie
| | - Taoufik Boubaker
- Université de Monastir, Avenue Taher Hadded B.P 56, Monastir 5000, Tunisie
| | - Jean-Claude Guillemin
- Univ Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR - UMR6226, F-35000 Rennes, France
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2
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Tipker RM, Muldoon JA, Jo J, Connors CS, Varga BR, Hughes RP, Glueck DS. Protonation of P-Stereogenic Phosphiranes: Phospholane Formation via Ring Opening and C-H Activation. ACS OMEGA 2023; 8:12565-12572. [PMID: 37033828 PMCID: PMC10077540 DOI: 10.1021/acsomega.3c00885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 03/09/2023] [Indexed: 06/19/2023]
Abstract
Protonation of cyclopropanes and aziridines is well-studied, but reactions of phosphiranes with acids are rare and have not been reported to result in ring opening. Treatment of syn-Mes*PCH2CHR (Mes* = 2,4,6-(t-Bu)3C6H2, R = Me or Ph, syn-1-2) or anti-Mes*PCH2CHPh (anti-2) with triflic acid resulted in regiospecific anti-Markovnikov C-protonation with ring opening and cyclophosphination of a Mes* ortho-t-Bu group to yield the phospholanium cations [PH(CH2CH2R)(4,6-(t-Bu)2-2-CMe2CH2C6H2)][OTf] (R = Me or Ph, 3-4), which were deprotonated with NEt3 to give phospholanes 5-6. Enantioenriched or racemic syn-1 both gave racemic 3. The byproduct [Mes*PH(CH2CH2Me)(OH)][OTf] (7) was formed from syn-1 and HOTf in the presence of water. Density functional theory calculations suggested that P-protonation followed by ring opening and hydride migration to C yields the phosphenium ion, [Mes*P(CH2CH2Me)][OTf], which undergoes C-H oxidative addition of an o-t-Bu methyl group. This work established a new reactivity pattern for phosphiranes.
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3
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Li Y, Zhang L, Luo S. Bond Energies of Enamines. ACS OMEGA 2022; 7:6354-6374. [PMID: 35224397 PMCID: PMC8867489 DOI: 10.1021/acsomega.1c06945] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 01/25/2022] [Indexed: 05/11/2023]
Abstract
Energetics of reactive intermediates underlies their reactivity. The availability of these data provides a rational basis for understanding and predicting a chemical reaction. We reported here a comprehensive computational study on the energetics of enamine intermediates that are fundamental in carbonyl chemistry. Accurate density functional theory (DFT) calculations were performed to determine the bond energies of enamines and their derived radical intermediates. These efforts led to the compilation of a database of enamine energetics including a thermodynamic index such as free-energy stability, bond dissociation energy (BDE), and acid dissociation constant (pK a) as well as a kinetic index such as nucleophilicity and electrophilicity. These data were validated by relating to experimentally determined parameters and their relevance and utility were discussed in the context of modern enamine catalysis. It was found that pK a values of enamine radical cations correlated well with redox potentials of their parent enamines, the former could be used to rationalize the proton-transfer behavior of enamine radical cations. An analysis of the BDE of enamine radical cations indicated that these species underwent facile β-C-H hydrogen transfer, in line with the known oxidative enamine catalysis. The enamine energetics offers the possibility of a systematic evaluation of the reactivities of enamines and related radicals, which would provide useful guidance in exploring new enamine transformations.
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Saeidian H, Ramezannejad M, Taheri S, Mirjafary Z. Toward tailoring of robust organobases based on extended π-systems: A density functional theory study of the carbonyl basicity. COMPUT THEOR CHEM 2020. [DOI: 10.1016/j.comptc.2019.112700] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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5
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Martín-Sómer A, Mó O, Yáñez M, Guillemin JC. Acidity enhancement of unsaturated bases of group 15 by association with borane and beryllium dihydride. Unexpected boron and beryllium Brønsted acids. Dalton Trans 2015; 44:1193-202. [DOI: 10.1039/c4dt02292k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
BeH2and BH3association with unsaturated bases of group 15 increases their acidity and changes the trend. Ethynyl : BeH2complexes unexpectedly behave as Be acids.
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Affiliation(s)
- Ana Martín-Sómer
- Departamento de Química
- Facultad de Ciencias
- Módulo 13
- Universidad Autónoma de Madrid
- 28049 Madrid
| | - Otilia Mó
- Departamento de Química
- Facultad de Ciencias
- Módulo 13
- Universidad Autónoma de Madrid
- 28049 Madrid
| | - Manuel Yáñez
- Departamento de Química
- Facultad de Ciencias
- Módulo 13
- Universidad Autónoma de Madrid
- 28049 Madrid
| | - Jean-Claude Guillemin
- Institut des Sciences Chimiques de Rennes
- École Nationale Supérieure de Chimie de Rennes
- CNRS
- UMR 6226
- 35708 Rennes Cedex 7
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Møllendal H, Samdal S, Gauss J, Guillemin JC. Synthesis, Microwave Spectrum, Quantum Chemical Calculations, and Conformational Composition of a Novel Primary Phosphine, Cyclopropylethynylphosphine, (C3H5C≡CPH2). J Phys Chem A 2014; 118:9419-28. [DOI: 10.1021/jp506169g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Harald Møllendal
- Centre for Theoretical
and Computational Chemistry (CTCC), Department of Chemistry, University of Oslo, P.O.
Box 1033, Blindern, NO-0315 Oslo, Norway
| | - Svein Samdal
- Centre for Theoretical
and Computational Chemistry (CTCC), Department of Chemistry, University of Oslo, P.O.
Box 1033, Blindern, NO-0315 Oslo, Norway
| | - Jürgen Gauss
- Institut für
Physikalische Chemie, Universität Mainz, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Jean-Claude Guillemin
- Institut
des Sciences
Chimiques de Rennes, École Nationale Supérieure de Chimie
de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837 35708 Rennes Cedex
7, France
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Baba G, Guillemin JC. Functionalised 1-Alkynylarsines: Synthesis, Characterisation, and Attempts of Rearrangement into Functionalised Arsaalkynes. Aust J Chem 2014. [DOI: 10.1071/ch14176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Functionalised 1-alkynylarsines were synthesised by reaction of the corresponding 1-alkynyltributylstannane on arsenic trichloride followed by chemoselective reduction of the formed 1-alkynyldichloroarsine by tributyltin hydride in the presence of small amounts of a radical inhibitor. Rearrangements of these compounds into the corresponding arsaalkynes were attempted.
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Kato T, Naka K. Arylaminomaleimides as a New Class of Aggregation-induced Emission-active Molecules Obtained from Organoarsenic Compounds. CHEM LETT 2012. [DOI: 10.1246/cl.2012.1445] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Takuji Kato
- Department of Chemistry and Materials Technology, Graduate School of Science and Technology, Kyoto Institute of Technology
| | - Kensuke Naka
- Department of Chemistry and Materials Technology, Graduate School of Science and Technology, Kyoto Institute of Technology
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Bouchoux G, Salpin JY. Gas-phase basicities of polyfunctional molecules. Part 2: Saturated basic sites. MASS SPECTROMETRY REVIEWS 2012; 31:353-390. [PMID: 21773983 DOI: 10.1002/mas.20343] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 05/27/2011] [Indexed: 05/31/2023]
Abstract
The present article is the second part of a general overview of the gas-phase protonation thermochemistry of polyfunctional molecules. The first part of the review (Mass Spectrom. Rev., 2007, 26:775-835) was devoted to the description of the physico-chemical concepts and of the methods of determination, both experimental and theoretical, of gas-phase basicity. Several clues concerning the structural and energetic aspects of the protonation of isolated species have been emphasized. In the present article, specific examples are examined. The field of investigation is limited to molecules containing a "saturated" basic site, that is, nitrogen or oxygen atoms engaged in simple σ bonds with their neighboring. Aliphatic, cyclic and aromatic poly-amines, amino alcohols, alcohols, ethers, and hydroxyl-ethers, are successively presented.
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Affiliation(s)
- Guy Bouchoux
- Ecole Polytechnique, Laboratoire des Mécanismes Réactionnels (DCMR), Département de Chimie, 91120 Palaiseau, France.
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Zevatskii YE, Samoilov DV. Empirical method for consideration of solvent effect on the dissociation constants of carboxylic acids. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2011. [DOI: 10.1134/s1070428008010065] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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11
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Nazari F, Ansari N. Theoretical insights into the trends in molecular properties of HCY, HSiY and HGeY molecules where Y = N, P, As. J Mol Model 2009; 16:1075-84. [PMID: 19924453 DOI: 10.1007/s00894-009-0600-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2009] [Accepted: 09/16/2009] [Indexed: 10/20/2022]
Abstract
To obtain insights into the factors that govern the analogy between HCN and its isostructures, HXY where X = C, Si, Ge and Y = N, P, As, the electronic and structural properties of these species in ground, cationic and anionic states at the QCISD, MP2 and B3LYP levels with 6-311++G** basis set and the first exited state with TD-B3LYP method have been presented. The results suggest that there are some correlations between structural and thermodynamic properties of the smallest member of this group (HCN) and heavier congers. The results of computation at these levels also predict the stability of HCAs in the ground state and HCN, HSiN and HGeN in the cationic state from the energetic point of view. Molecular electrostatic potential map inspection shows that in HXN species nucleophilic region positions on N atom but in HXP and HXAs molecules by increasing the size of central atom nucleophilic region shifts from region near X atom toward terminal atom. Finally, the nature of bonds of HXY molecules are systematically studied through atoms in molecules (AIM) and natural bond orbital analyses (NBO).
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Affiliation(s)
- Fariba Nazari
- Faculty of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), 5195-1159, Zanjan, 45195, Iran.
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12
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Hurtado M, Yáñez M, Guillemin JC. Enhanced acidity of cyclopenta-2,4-dienylborane and its Al and Ga analogues. The role of aromatization. Phys Chem Chem Phys 2009; 11:8759-66. [PMID: 20449020 DOI: 10.1039/b906045f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The intrinsic acidity of cyclopenta-2,4-dienylborane and its Al and Ga analogues has been compared to that of cyclopentadiene by means of B3LYP/6-311+G(3df,2p)//CCSD/6-311+G(d,p) calculations. Substitution of one of the H atoms of the C(sp(3))H(2) group of cyclopentadiene by an XH(2) (X = B, Al, Ga) leads to an acidity enhancement which is significantly large for the boron derivative (95 kJ mol(-1)); but much smaller for the Al and Ga containing analogues. This acidity enhancement reflects the stabilization of the anion, in the substituted derivatives, due to a significant reinforcement of the C-X bond. This enhancement is however smaller than expected because, although XH(2) (X = B, Al, Ga) substitution leads to a significant aromatization of the neutral compounds, the aromaticity significantly decreases upon deprotonation, whereas for the unsubstituted parent compound is the other way around. Cyclopenta-2,4-dienylborane and its Al and Ga analogues behave as highly fluxional systems.
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Affiliation(s)
- Marcela Hurtado
- Departamento de Química, C-9. Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain
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13
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Benidar A, Khater B, Guillemin JC, Gámez JA, Yáñez M. Gas-Phase Infrared Spectra of Vinyl Selenol and Vinyl Tellurol. J Phys Chem A 2009; 113:12857-63. [DOI: 10.1021/jp906075j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Abdessamad Benidar
- Institut de Physique de Rennes, Equipe Astrochimie Expérimentale UMR 6251 CNRS, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
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Khater B, Guillemin JC, Benidar A, Bégué D, Pouchan C. Vinylphosphine-borane: Synthesis, gas phase infrared spectroscopy, and quantum chemical vibrational calculations. J Chem Phys 2008; 129:224308. [DOI: 10.1063/1.3035902] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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15
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Eizaguirre A, Mó O, Yáñez M, Guillemin JC. α,β-Unsaturated and Saturated Derivatives of Be, Mg, and Ca: Are They Carbon or Metal Acids in the Gas Phase? Chemistry 2008; 14:10423-9. [DOI: 10.1002/chem.200801012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Gámez J, Guillemin JC, Mó O, Yáñez M. Strong Dissimilarities Between the Gas-Phase Acidities of Saturated and α,β-Unsaturated Boranes and the Corresponding Alanes and Gallanes. Chemistry 2008; 14:2201-8. [DOI: 10.1002/chem.200701254] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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17
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Bouchoux G. Gas-phase basicities of polyfunctional molecules. Part 1: Theory and methods. MASS SPECTROMETRY REVIEWS 2007; 26:775-835. [PMID: 17854059 DOI: 10.1002/mas.20151] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The experimental and theoretical methods of determination of gas-phase basicities, proton affinities and protonation entropies are presented in a tutorial form. Particularities and limitations of these methods when applied to polyfunctional molecules are emphasized. Structural effects during the protonation process in the gas-phase and their consequences on the corresponding thermochemistry are reviewed and classified. The role of the nature of the basic site (protonation on non-bonded electron pairs or on pi-electron systems) and of substituent effects (electrostatic and resonance) are first examined. Then, linear correlations observed between gas-phase basicities and ionization energies or substituent constants are recalled. Hydrogen bonding plays a special part in proton transfer reactions and in the protonation characteristics of polyfunctional molecules. A survey of the main properties of intermolecular and intramolecular hydrogen bonding in both neutral and protonated species is proposed. Consequences on the protonation thermochemistry, particularly of polyfunctional molecules are discussed. Finally, chemical reactions which may potentially occur inside protonated clusters during the measurement of gas-phase basicities or inside a protonated polyfunctional molecule is examined. Examples of bond dissociations with hydride or alkyl migrations, proton transport catalysis, tautomerization, cyclization, ring opening and nucleophilic substitution are presented to illustrate the potentially complex chemistry that may accompany the protonation of polyfunctional molecules.
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Affiliation(s)
- Guy Bouchoux
- Laboratoire des Mécanismes Réactionnels, Département de Chimie, Ecole Polytechnique, 91120 Palaiseau, France.
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18
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Jaramillo P, Pérez P, Fuentealba P. Relationship between basicity and nucleophilicity. J PHYS ORG CHEM 2007. [DOI: 10.1002/poc.1251] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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19
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Min SJ, Jones GO, Houk KN, Danishefsky SJ. Creating Quaternary Centers with High Exo Stereoselectivity Using Activated α-Alkynyl Dienophiles. J Am Chem Soc 2007; 129:10078-9. [PMID: 17655309 DOI: 10.1021/ja073528d] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sun-Joon Min
- Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA
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20
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Luna A, Mó O, Yáñez M, Gal JF, Maria PC, Guillemin JC. Gas-Phase Protonation and Deprotonation of Acrylonitrile Derivatives NCCHCHX (X=CH3, NH2, PH2, SiH3). Chemistry 2006; 12:9254-61. [PMID: 16991171 DOI: 10.1002/chem.200600154] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A combined experimental and theoretical study on the gas-phase basicity and acidity of a series of cyanovinyl derivatives is presented. The gas-phase basicities and acidities of (N[triple chemical bond]C--CH==CH--X, X=CH(3), NH(2)) were obtained by means of Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry techniques. The corresponding calculated values were obtained at the G3B3 level of theory. The effects of exchanging CH(3) for SiH(3), and NH(2) for PH(2), were analyzed at the same level of theory. For the neutral molecules, the Z isomer is always the dominant species under standard gas-phase conditions at 298 K. The loss of the proton from the substituent X was found systematically to be much more favorable than deprotonation of the HC==CH linking group. The corresponding isomeric E ion is much more stable than the Z ion, so that only the former should be found in the gas phase. The most significant structural changes upon deprotonation occur for the methyl and amino derivatives because, in both cases, deprotonation of X leads to a significant charge delocalization in the corresponding anion. Protonation takes place systematically at the cyano group, whereby the isomeric E ion is again more stable than the Z ion. Push-pull effects explain the preference of aminoacrylonitrile to be protonated at the cyano group, which also explains the high basicity of this derivative relative to other members of the analyzed series that present rather similar gas-phase basicities, GB approximately 780 kJ mol(-1), indicating that the different nature of the substituents has only a weak effect on the intrinsic basicity of the cyano group. The cyanovinyl derivatives have a significantly stronger gas-phase acidity than that of the corresponding vinyl compounds CH(2)==CH--X. This acidity-strengthening effect of the cyano group is attributed to the greater stabilization of the anion with respect to the corresponding neutral compound.
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Affiliation(s)
- Alberto Luna
- Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain
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Guillemin JC, Legoupy S, Batten S, Legon A. The ground-state rotational spectrum and molecular geometry of ethynylstannane. Phys Chem Chem Phys 2006; 8:2145-52. [PMID: 16751872 DOI: 10.1039/b517507k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ground-state rotational spectra of 24 isotopomers of ethynylstannane have been observed by pulsed-jet, Fourier-transform microwave spectroscopy. The spectroscopic constants, B(0,)D(J) and D(JK) are reported for symmetric-top isotopomers H(3)(n)Sn(12)C(12)CH, where n = 116, 117, 118, 119, 120, 122 and 124, D(3)(n)Sn(12)C(12)CH, where n = 116, 118, 120, 122 and 124, H(3)(n)Sn(13)C(12) CH and H(3)(n)Sn(12)C(13)CH , where n = 116,118 and 120, and H(3)(n)Sn(12)C(12)CD, where n = 116, 118 and 120. In addition, the values of A(0), B(0), C(0), Delta(J) and Delta(JK) were obtained for the three asymmetric-top isotopomers DH(2)(n)Sn(12)C(12)CH, where n = 116, 118 and 120. Hyperfine structure was resolved and assigned in the transitions of the isotopomers H(3)(n)SnCCD, where n = 116, 118 and 120, and in the isotopomers H(3)(117)SnCCH and H(3)(119)SnCCH. In the former group, the hyperfine structure arises from D nuclear quadrupole coupling while in the latter group its origin lies in the spin-rotation coupling of the I = 1/2 Sn nuclear spin to the rotational motion. For these isotopomers, D nuclear quadrupole and spin-rotation coupling constants are determined where appropriate. The rotational constants obtained for the 24 isotopomers of H(3)SnCCH were used to obtain the following types of molecular geometry for ethynylstannane: r(0), r(s), and r(m).
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Affiliation(s)
- Jean-Claude Guillemin
- Laboratoire de Synthèse et Activation de Biomolécules, UMR CNRS 6052, ENSCR, Institut de Chimie de Rennes, 35700 Rennes, France
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Benidar A, Guillemin JC, Mó O, Yañez M. Infrared Spectra of a Species of Astrochemical Interest: Aminoacrylonitrile (3-Amino-2-propenenitrile). J Phys Chem A 2005; 109:4705-12. [PMID: 16833811 DOI: 10.1021/jp050148a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ammonia easily reacts on cyanoacetylene in the gas phase or in a solvent to form the Z- and E-isomers of aminoacrylonitrile (3-amino-2-propenenitrile, 2). This kinetically stable enamine presents interest for its possible presence in the interstellar medium, the comets, the atmospheres of Planets including the Primitive Earth, and from a theoretical point of view. B3LYP/6-311+G(3df,2p) and G2 calculations indicate that the imine isomer is significantly less stable than the enamine 2. DFT and G2 calculations indicate that the Z-isomer of compound 2 lies ca. 8.0 kJ mol(-1) lower in energy than the E-isomer. The infrared spectra of the aminoacrylonitrile, in both the gas and condensed phases were recorded in the range 500-4000 cm(-1). Consistent with the theoretical calculations, the imine and the E-isomer of the enamine have never been detected in the infrared spectrum of a gaseous sample and only the Z-isomer has been observed. With a neat sample in the condensed phase, IR spectra of a 1:1 and 20:1/Z:E mixtures were recorded. The comparison of these data with the spectrum of the Z-isomer in the gas phase allowed us to deduce the IR spectrum of the E-isomer. The E-Z isomerization takes place through a torsion around the C=C bond. A possible mechanism involving a previous enamine-imine tautomerism must be discarded because it implies a much larger barrier than the direct isomerization process. Consistently, the presence of a deuterium atom has not been observed on the sp2 carbon of the products of distillation of a 1:1/E:Z mixture of the NCCH=CHND2.
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Affiliation(s)
- Abdessamad Benidar
- PALMS, UMR CNRS 6627, Université de Rennes 1, 35042 Rennes, France, Laboratoire de Synthèse et Activation de Biomolécules, UMR CNRS 6052, ENSCR, Institut de Chimie de Rennes, 35700 Rennes, France
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Guillemin JC, Riague EH, Gal JF, Maria PC, Mó O, Yáñez M. Acidity Trends in α,β-Unsaturated Sulfur, Selenium, and Tellurium Derivatives: Comparison with C-, Si-, Ge-, Sn-, N-, P-, As-, and Sb-Containing Analogues. Chemistry 2005; 11:2145-53. [PMID: 15714535 DOI: 10.1002/chem.200400989] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The gas-phase acidity of CH3-CH2XH (X=S, Se, Te), CH2=CHXH (X=S, Se, Te) and PhXH (X=S, Se) compounds was measured by means of Fourier transform ion cyclotron resonance mass spectrometry. To analyze the role that unsaturation plays on the intrinsic acidity of these systems, a parallel theoretical study, in the framework of the G2 and the G2(MP2) theories, was carried out for all ethyl, ethenyl (vinyl), ethynyl, and phenyl O-, S-, Se-, and Te-containing derivatives. Unsaturated compounds are stronger acids than their saturated analogues, because of the strong pi-electron donor ability of the heteroatoms that contributes to a large stabilization of the unsaturated anions. Ethynyl derivatives are stronger acids than vinyl compounds, while phenyl derivatives have an intrinsic acidity intermediate between that of the corresponding vinyl and ethynyl analogues. The CH2=CHXH vinyl compounds (enol-like) behave systematically as slightly stronger acids than their CH3-C(H)X (keto-like) tautomers. Vinyl derivatives are stronger acids than ethyl compounds, because the anion stabilization attributable to unsaturation is greater than that undergone in the neutral compounds. Conversely, the enhanced acidity of the ethynyl derivatives with respect to the vinyl compounds is due to two concomitant effects, the stabilization of the anion and the destabilization of the neutral compound. The acidities of ethyl, vinyl, and ethynyl derivatives containing heteroatoms of Groups 14, 15, and 16 of the periodic table are closely related, and reflect the differences in electronegativity of the CH3CH2-, CH2=CH-, and CH[triple chemical bond]C- groups.
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Affiliation(s)
- Jean-Claude Guillemin
- Laboratoire de Synthèse et Activation de Biomolécules, UMR CNRS 6052, ENSCR, Institut de Chimie de Rennes, 35700 Rennes Cedex, France.
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Quintanilla E, Dávalos JZ, Abboud JLM, Alcamí M, Cabildo MP, Claramunt RM, Elguero J, Mó O, Yáñez M. Why Does Pivalaldehyde (Trimethylacetaldehyde) Unexpectedly Seem More Basic Than 1-Adamantanecarbaldehyde in the Gas Phase? FT-ICR and High-Level Ab Initio Studies. Chemistry 2005; 11:1826-32. [PMID: 15669041 DOI: 10.1002/chem.200400781] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Fourier transform ion cyclotron resonance spectroscopy (FT ICR) techniques, including collision-induced dissociation (CID) methodology, were applied to the study of the gas-phase protonation of pivalaldehyde (1) and 1-adamantanecarbaldehyde (2). A new synthetic method for 2 was developed. The experiments, together with a thorough computational study involving ab initio and density functional theory (DFT) calculations of high level, conclusively show that upon monoprotonation in the gas phase, compound 1 yields monoprotonated methyl isopropyl ketone 3. The mechanism of this gas-phase acid-catalyzed isomerization is different from that reported by Olah and Suryah Prakash for the reaction in solution. In the latter case, isomerization takes place through the diprotonation of 1.
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Affiliation(s)
- Esther Quintanilla
- Instituto de Química Física Rocasolano, CSIC, C/Serrano 119, 28006 Madrid, Spain
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Carrasco N, González-Nilo F, Rezende MC. Relative solvation and strength of polycyano- and polynitromethanes in water: a study with molecular dynamics simulations. J PHYS ORG CHEM 2004. [DOI: 10.1002/poc.867] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Galiano L, Alcamí M, Mó O, Yáñez M. Gas-phase chemistry of ethynylamine, -phosphine and -arsine. Structure and stability of their Cu+ and Ni+ complexes. Chemphyschem 2003; 4:72-8. [PMID: 12596468 DOI: 10.1002/cphc.200390011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The Cu+ and Ni+ binding energies of ethynylamine, ethynylphosphine and ethynylarsine have been calculated at the B3LYP/6-311 + G(2df,2p)//B3LYP/6-311G(d,p) level of theory. Significant differences between nitrogen-containing and phosphorus- or arsenic-containing compounds have been found regarding structural effects upon metal cation association. While for ethynylamine the global minimum of the potential energy surface corresponds to the complex in which the metal cation binds to the beta-carbon, for ethynylphosphine the most favourable process corresponds to phosphorus attachment. For ethynylarsine, the conventional pi-complex is the most stable one. This behavior resembles that found for the corresponding vinyl analogues, with the only exception being the arsenic derivative. The calculated Cu+ and Ni+ binding energies for attachment to the heteroatom follow a different trend, P > As > N, to that predicted for the corresponding proton affinities, P > N > As. Cu+ and Ni+ binding energies are almost identical when the metal cation binds to the heteroatom. However, Ni+ binding energies are slightly larger than Cu+ binding energies when the metal cation interacts with the C identical to C bond.
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Affiliation(s)
- Luis Galiano
- Departamento de Química C-9, Universidad Autónoma de Madrid Cantoblanco 28049 Madrid, Spain
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Zilberg S, Haas Y. Isomerization around a CN double bond and a CC double bond with a nitrogen atom attached: thermal and photochemical routes. Photochem Photobiol Sci 2003; 2:1256-63. [PMID: 14717219 DOI: 10.1039/b306137j] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Longuet-Higgins phase change theorem is used to show that, in certain photochemical reactions, a single product is formed via a conical intersection. The cis-trans isomerization around the double bond in the formaldiminium cation and vinylamine are shown to be possible examples. This situation is expected to hold when the reactant can be converted to the product via two distinct elementary ground-state reactions that differ in their phase characteristics. In one, the total electronic wavefunction preserves its phase in the reaction; in the other, the phase is inverted. Under these conditions, a conical intersection necessarily connects the first electronic excited state to the ground state, leading to rapid photochemical isomerization following optical excitation. Detailed quantum chemical calculations support the proposed model. The possibility that a similar mechanism is operative in other systems, among them the rapid photo-induced cis-trans isomerization of longer protonated Schiff bases (the parent chromophores of rhodopsins), is discussed.
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Affiliation(s)
- Shmuel Zilberg
- Department of Physical Chemistry, Farkas Center for Light Induced Processes, The Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
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del Carmen Sicilia M, Mó O, Yáñez M, Guillemin JC, Gal JF, Maria PC. Is allylphosphine a carbon or a phosphorus base in the gas phase? EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2003; 9:245-255. [PMID: 12939477 DOI: 10.1255/ejms.558] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The gas-phase basicity of allylphosphine (2-propenylphosphine) was measured by means of Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry techniques. A complete survey of the allylphosphine-H(+) potential energy surface, carried out through the use of high-level G2(MP2) and B3LYP/6-311+G(3df,2p) calculations, allows us to conclude that, under low-pressure, low-energy ICR conditions, the interaction between the protonated reference base, B(ref)H(+), and allylphosphine leads to a complex in which B(ref)H(+) attaches to the phosphorus atom of allylphosphine, where the electrostatic potential is strongly attractive. Hence, in the first step only the phosphorus protonated species should be formed. Its isomerization to yield the C(beta)-protonated form, which is the global minimum of the potential energy surface, implies a very high activation barrier that cannot be overtaken under normal experimental ICR conditions. Therefore, the main conclusion of our study is that allylphosphine behaves as a phosphorus base in the gas phase, even though the C(beta)-protonated structure is the most stable protonated species. We have also shown that both C(beta)- and C(gamma)-protonation triggers a cyclization of the system. An analysis of the bonding of the different protonated species as compared with that of the neutral system is presented.
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Corral I, Mó O, Yáñez M. The importance of agostic-type interactions for the binding energies of Ni+to saturated and α,β-unsaturated alkanes, silanes and germanes. NEW J CHEM 2003. [DOI: 10.1039/b305532a] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Galiano L, Alcamí M, Mó O, Yáñez M. Gas-Phase Chemistry of Ethyl and Vinyl Amines, Phosphines, and Arsines: A DFT Study of the Structure and Stability of Their Cu+ Complexes. J Phys Chem A 2002. [DOI: 10.1021/jp026386c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- L. Galiano
- Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco 28049, Madrid, Spain
| | - M. Alcamí
- Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco 28049, Madrid, Spain
| | - O. Mó
- Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco 28049, Madrid, Spain
| | - M. Yáñez
- Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco 28049, Madrid, Spain
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Benidar A, Le Doucen R, Guillemin JC, Mó O, Yáñez M. Vibrational Spectra of Vinylarsine and Vinylstibine. An Experimental and Theoretical Study. J Phys Chem A 2002. [DOI: 10.1021/jp0145558] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | | | - Jean-Claude Guillemin
- Laboratoire de Synthèse et Activation de Biomolécules, UMR CNRS 6052, ENSCR, 35700 Rennes, France
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Riague EH, Guillemin JC. Synthesis and Characterization of Allylic and Propargylic Selenols. Organometallics 2001. [DOI: 10.1021/om010453s] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- El Hassan Riague
- Laboratoire de Synthèses et Activations de Biomolécules, UMR CNRS 6052, ENSCR, 35700 Rennes, France
| | - Jean-Claude Guillemin
- Laboratoire de Synthèses et Activations de Biomolécules, UMR CNRS 6052, ENSCR, 35700 Rennes, France
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Gal JF, Decouzon M, Maria PC, González AI, Mó O, Yáñez M, El Chaouch S, Guillemin JC. Acidity trends in alpha,beta-unsaturated alkanes, silanes, germanes, and stannanes. J Am Chem Soc 2001; 123:6353-9. [PMID: 11427060 DOI: 10.1021/ja004079j] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The gas-phase acidity of ethyl-, vinyl-, ethynyl-, and phenyl-substituted silanes, germanes, and stannanes has been measured by means of FT-ICR techniques. The effect of unsaturation on the intrinsic acidity of these compounds and the corresponding hydrocarbons was analyzed through the use of G2 ab initio and DFT calculations. In this way, it was possible to get a general picture of the acidity trends within group 14. As expected, the acid strength increases down the group, although the acidity differences between germanium and tin derivatives are already rather small. As has been found before for amines, phosphines, and arsines, the carbon, silicon, germanium, and tin alpha,beta-unsaturated compounds are stronger acids( )than their saturated analogues. The acidifying effect of unsaturation is much larger for carbon than for Si-, Ge-, and Sn-containing compounds. The allyl anion is better stabilized by resonance than its Si, Ge, and Sn analogues, [CH(2)(-)(delta)--CH(+)(delta)(') --CH(2)(-)(delta)](-) vs [CH(2)(-)(delta)()II = CH(-)(delta)()III - XH(2)(-)(delta)()IV](-) (X = Si, Ge, Sn). The enhanced acid strength of unsaturated compounds is essentially due to a greater stabilization of the anion with respect to the neutral, because the electronegativity of the alpha,beta-unsaturated carbon group increases with its degree of unsaturation. The phenyl derivatives are systematically weaker acids than the corresponding ethynyl derivatives by 15-20 kJ mol(-)(1). Experimentally, toluene acidity is very close to that of propyne, because the deprotonation of propyne takes place preferentially at the =CH group rather than at the -CH(3) group.
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Affiliation(s)
- J F Gal
- Chimie des Matériaux Organiques et Métalliques, Université de Nice-Sophia Antipolis, Parc Valrose, 06108 Nice Cedex 2, France
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Alcamí M, Mó O, Yáñez M. Computational chemistry: a useful (sometimes mandatory) tool in mass spectrometry studies. MASS SPECTROMETRY REVIEWS 2001; 20:195-245. [PMID: 11835306 DOI: 10.1002/mas.10005] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In this review, we present a brief summary of the theoretical methods most frequently used in gas-phase ion chemistry. In subsequent sections, the performance of these methods is analyzed, paying attention to the reliability of geometries, vibrational frequencies, energies, and entropies. The possible pathologies of the different methods, in the form of instabilities of the wave function or spin contamination problems, are discussed. Several examples are presented to illustrate the usefulness of ab initio or density functional theory (DFT) methods to predict the existence of elusive molecules and/or to characterize non-conventional structures, and to rationalize the charge redistributions normally associated with ion-molecule interactions and which result in bond-weakening or bond-reinforcement effects. Finally, the role of non-classical structures in ion-molecule interactions is also illustrated with different examples.
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Affiliation(s)
- M Alcamí
- Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain
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Guillemin JC, El Chaouch S, Bouayad A, Janati T. Partial pressures and nature of products. Application to the photolysis of PH3 and NH3 in the atmosphere of Jupiter and Saturn. ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 2001; 27:245-253. [PMID: 11605639 DOI: 10.1016/s0273-1177(01)00054-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The photolysis of mixtures of gases containing NH3 or PH3 presents important differences mainly due to the strength of the X-H bond. On some examples, these differences are evidenced and the consequences for mixtures of gases containing these two compounds are shown: the photolysis of ammonia and ethylene mainly gives ethyl-, butyl- and hexylamine whereas the photolysis of phosphine and ethylene leads to ethyl- and vinylphosphine. When gaseous mixtures of NH3, PH3 and ethylene are photolyzed together, the presence of phosphine dramatically decreases the formation of nitrogen derivatives. The relevance of such lab studies to the atmospheres of Jupiter and Saturn is discussed.
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Affiliation(s)
- J C Guillemin
- Laboratoire de Syntheses et Activations de Biomolecules, UMR CNRS 6052, ENSCR, 35700 Rennes, France.
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38
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Lamsabhi M, Alcamí M, Mó O, Bouab W, Esseffar M, Abboud JLM, Yáñez M. Are the Thiouracils Sulfur Bases in the Gas-phase? J Phys Chem A 2000. [DOI: 10.1021/jp000071k] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- M. Lamsabhi
- Departement de Chimie, Faculté des Sciences Semlalia Université Cadi Ayyad., Marrakech, Morocco, Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco, and Instituto “Rocasolano”, C.S.I.C., Serrano, 119, 28006-Madrid, Spain
| | - M. Alcamí
- Departement de Chimie, Faculté des Sciences Semlalia Université Cadi Ayyad., Marrakech, Morocco, Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco, and Instituto “Rocasolano”, C.S.I.C., Serrano, 119, 28006-Madrid, Spain
| | - O. Mó
- Departement de Chimie, Faculté des Sciences Semlalia Université Cadi Ayyad., Marrakech, Morocco, Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco, and Instituto “Rocasolano”, C.S.I.C., Serrano, 119, 28006-Madrid, Spain
| | - W. Bouab
- Departement de Chimie, Faculté des Sciences Semlalia Université Cadi Ayyad., Marrakech, Morocco, Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco, and Instituto “Rocasolano”, C.S.I.C., Serrano, 119, 28006-Madrid, Spain
| | - M. Esseffar
- Departement de Chimie, Faculté des Sciences Semlalia Université Cadi Ayyad., Marrakech, Morocco, Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco, and Instituto “Rocasolano”, C.S.I.C., Serrano, 119, 28006-Madrid, Spain
| | - J. L.-M. Abboud
- Departement de Chimie, Faculté des Sciences Semlalia Université Cadi Ayyad., Marrakech, Morocco, Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco, and Instituto “Rocasolano”, C.S.I.C., Serrano, 119, 28006-Madrid, Spain
| | - M. Yáñez
- Departement de Chimie, Faculté des Sciences Semlalia Université Cadi Ayyad., Marrakech, Morocco, Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco, and Instituto “Rocasolano”, C.S.I.C., Serrano, 119, 28006-Madrid, Spain
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