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Abstract
The synthesis, characterization and reactivity of several bi- and tridentate, N-ligated manganese carbonyl trifluoromethyl complexes are presented. These complexes exhibit elongated Mn–CCF3 bonds (versus Mn(CF3)(CO)5), suggesting a lability that could be utilized for the transfer or insertion of the CF3 functional group into organic substrates. Unlike their Mn–X congeners (X = Cl, Br), these Mn–CF3 complexes exhibit a preference for hard donor ancillary ligands, thus enabling the synthesis of 4 N-ligated Mn–CF3 complexes including a mixed-donor tridentate complex using an NNS Schiff base ([2-(methylthio)-N-(1-(pyridin-2-yl)ethylidene)aniline]). Although we have not yet identified efficient CF3 transfer reactions, fluoride abstraction from the Mn–CF3 complexes using trimethylsilyl triflate affords the first stable Mn fluorocarbenes as evidenced by 19F NMR spectroscopy.
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Kraft BM, Clot E, Eisenstein O, Brennessel WW, Jones WD. Mechanistic investigation of vinylic carbon–fluorine bond activation of perfluorinated cycloalkenes using Cp*2ZrH2 and Cp*2ZrHF. J Fluor Chem 2010. [DOI: 10.1016/j.jfluchem.2010.05.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Schaub T, Fischer P, Steffen A, Braun T, Radius U, Mix A. C−F Activation of Fluorinated Arenes using NHC-Stabilized Nickel(0) Complexes: Selectivity and Mechanistic Investigations. J Am Chem Soc 2008; 130:9304-17. [DOI: 10.1021/ja074640e] [Citation(s) in RCA: 209] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Thomas Schaub
- Institut für Anorganische Chemie der Universität Karlsruhe, 76131 Karlsruhe, Germany, Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany, and Fakultät für Chemie, Universität Bielefeld, Universitätsstrasse 25, 33615 Bielefeld, Germany
| | - Peter Fischer
- Institut für Anorganische Chemie der Universität Karlsruhe, 76131 Karlsruhe, Germany, Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany, and Fakultät für Chemie, Universität Bielefeld, Universitätsstrasse 25, 33615 Bielefeld, Germany
| | - Andreas Steffen
- Institut für Anorganische Chemie der Universität Karlsruhe, 76131 Karlsruhe, Germany, Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany, and Fakultät für Chemie, Universität Bielefeld, Universitätsstrasse 25, 33615 Bielefeld, Germany
| | - Thomas Braun
- Institut für Anorganische Chemie der Universität Karlsruhe, 76131 Karlsruhe, Germany, Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany, and Fakultät für Chemie, Universität Bielefeld, Universitätsstrasse 25, 33615 Bielefeld, Germany
| | - Udo Radius
- Institut für Anorganische Chemie der Universität Karlsruhe, 76131 Karlsruhe, Germany, Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany, and Fakultät für Chemie, Universität Bielefeld, Universitätsstrasse 25, 33615 Bielefeld, Germany
| | - Andreas Mix
- Institut für Anorganische Chemie der Universität Karlsruhe, 76131 Karlsruhe, Germany, Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany, and Fakultät für Chemie, Universität Bielefeld, Universitätsstrasse 25, 33615 Bielefeld, Germany
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Steffen A, Sladek MI, Braun T, Neumann B, Stammler HG. Catalytic C−C Coupling Reactions at Nickel by C−F Activation of a Pyrimidine in the Presence of a C−Cl Bond: The Crucial Role of Highly Reactive Fluoro Complexes. Organometallics 2005. [DOI: 10.1021/om050080l] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Andreas Steffen
- Fakultät für Chemie, Universität Bielefeld, Postfach 100131, 33501 Bielefeld, Germany
| | - Marianna I. Sladek
- Fakultät für Chemie, Universität Bielefeld, Postfach 100131, 33501 Bielefeld, Germany
| | - Thomas Braun
- Fakultät für Chemie, Universität Bielefeld, Postfach 100131, 33501 Bielefeld, Germany
| | - Beate Neumann
- Fakultät für Chemie, Universität Bielefeld, Postfach 100131, 33501 Bielefeld, Germany
| | - Hans-Georg Stammler
- Fakultät für Chemie, Universität Bielefeld, Postfach 100131, 33501 Bielefeld, Germany
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Clot E, Mégret C, Kraft BM, Eisenstein O, Jones WD. Defluorination of Perfluoropropene Using Cp*2ZrH2 and Cp*2ZrHF: A Mechanism Investigation from a Joint Experimental−Theoretical Perspective. J Am Chem Soc 2004; 126:5647-53. [PMID: 15113236 DOI: 10.1021/ja0499243] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cp*(2)ZrH(2) (1) (Cp* = pentamethylcyclopentadienyl) reacts with perfluoropropene (2) to give Cp*(2)ZrHF (3) and hydrodefluorinated products under very mild conditions. Initial C-F bond activation occurs selectively at the vinylic terminal position of the olefin to exchange fluorine for hydrogen. Subsequent hydrodefluorination leads to the formation of the n-propylhydride complex Cp*(2)ZrH(CH(2)CH(2)CH(3)), which can be cleaved with dihydrogen to give propane and 1. A theoretical study of the reaction of Cp*(2)ZrH(2) (Cp* = cyclopentadienyl) and CF(2)[double bond]CF(CF(3)) has been undertaken. Several mechanisms have been examined in detail using DFT(B3PW91) calculations and are discussed for this H/F exchange: (a) internal olefin insertion/beta-fluoride elimination, (b) external olefin insertion/beta-fluoride elimination, and (c) F/H metathesis from either an inside or outside approach. Of these, the first case is found to be energetically preferred. Selective defluorination at the terminal carbon has been shown to be favored over defluorination at the substituted and allylic carbons.
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Affiliation(s)
- Eric Clot
- Laboratoire de Structure et Dynamique des Systèmes Moléculaires et Solides (UMR 5636), Case Courrier 14, Université Montpellier 2, 34095 Montpellier Cedex 5, France
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Yaozeng H, Jisen L, Jianqiang Z, Qiwen W, Meimei G. Oligomerization of perfluoropropylene catalyzed by π-bis(arene)chromium(0) complexes. J Organomet Chem 1981. [DOI: 10.1016/s0022-328x(00)86098-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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