Hydrogen Migration in Transition Metal Alkyne and Related Complexes
- 25 September 1985
- journal article
- research article
- Published by Wiley in Helvetica Chimica Acta
- Vol. 68 (6) , 1461-1506
- https://doi.org/10.1002/hlca.19850680602
Abstract
The electronic and structural characteristics of the reaction interconverting a l‐alkyne complex into a vinylideneviaa 1,2 hydrogen shift are examined. In a mononuclear system, initial slippage of the alkyne to an η1geometry is indicated. The subsequent step is shown to be analogous to the isomerization of a methylvinyl cation. We conclude that an alternative route involving a hydrido‐acetylide species will be of much higher energy. A concerted shift in binuclear and trinuclear systems is ruled out, based on the loss of a strong bonding interaction between the alkyne and the metallic piece, in the transition state. In trinuclear systems, a mechanism for the isomerization is suggested involving prior oxidative addition of the CH bond across a metal‐metal bond. The metallic piece in this case assists the transformation. The discussion is extended to other reactions featuring hydrogen shifts; these include the intramolecular formation of a binuclear vinylidene from a 1,2‐hydrido‐acetylide complex, the isomerization of a binuclear μ‐alkylidyne into a μ‐vinyl geometry and the transfer of a bridging hydrogen onto a capping hydrocarbon fragment in trinuclear cluster complexes.Keywords
This publication has 149 references indexed in Scilit:
- Reactivity of acetylenes coordinated to cobalt. 6. Preparation and structure of (.mu.-C4O2R1R2)(.mu.-C:CR3R4)Co2(CO)6 compounds. Unexpected 1,2-shift of the substituents of coordinated haloacetylenesInorganic Chemistry, 1983
- Mechanism, regiochemistry, and stereochemistry of the insertion reaction of alkynes with methyl(2,4-pentanedionato)(triphenylphosphine)nickel. A cis insertion that leads to trans kinetic productsJournal of the American Chemical Society, 1981
- Acetylene isomerization by manganese(I): preparation and structure of (C5H5)2Mn2(CO)4CCH2Inorganic Chemistry, 1979
- Crystal and molecular structures of HFe3(CH3C:NH)(CO)9 and HFe3(N:CHCH3)(CO)9, isomeric cluster complexes derived from the reduction of acetonitrileJournal of the American Chemical Society, 1979
- Synthesis of triiron carbonyl cluster complexes containing isomeric triply bridging acimidoyl or alkylidenimido group derived from the reduction of organic nitrilesJournal of the American Chemical Society, 1979
- Organometallic models for possible Fischer-Tropsch intermediates. Synthesis, structure, and reactions of a formaldehyde complex of osmiumJournal of the American Chemical Society, 1979
- Electron correlation theories and their application to the study of simple reaction potential surfacesInternational Journal of Quantum Chemistry, 1978
- Stable dimethyl, methyl, and unsubstituted vinylidene complexesJournal of the American Chemical Society, 1978
- Vinyl triflate chemistry: unsaturated cations and carbenesAccounts of Chemical Research, 1978
- Chemistry and the carbon arcAccounts of Chemical Research, 1973