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Intramolecular Hydrogen Transfer Reactions Catalyzed by Pentamethylcyclopentadienyl Rhodium and Cobalt Olefin Complexes: Mechanistic Studies.

ABSTRACT: The mechanism of intramolecular transfer dehydrogenation catalyzed by [Cp^*M(VTMS)₂] (1, M=Rh, 2, M=Co, Cp* = C₅Me₅, VTMS = vinyltrimethylsilane) complexes has been studied using vinyl silane protected alcohols as substrates. Deuterium-labeled substrates have been synthesized and the regioselectivity of H/D transfers investigated using ¹H and ²H NMR spectroscopy. The labeling studies establish a regioselective pathway consisting of alkene directed α C-H activation, 2,1 alkene insertion, and finally β-hydride elimination to give silyl enol ether products.

SUBMITTER: Bolig AD

PROVIDER: S-EPMC4742333 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Intramolecular Hydrogen Transfer Reactions Catalyzed by Pentamethylcyclopentadienyl Rhodium and Cobalt Olefin Complexes: Mechanistic Studies.

Bolig Andrew D AD Lyons Thomas W TW DiSalvo Darren T DT Brookhart Maurice M

Polyhedron 20160101 Pt A

The mechanism of intramolecular transfer dehydrogenation catalyzed by [Cp*M(VTMS)2] (1, M=Rh, 2, M=Co, Cp* = C5Me5, VTMS = vinyltrimethylsilane) complexes has been studied using vinyl silane protected alcohols as substrates. Deuterium-labeled substrates have been synthesized and the regioselectivity of H/D transfers investigated using 1H and 2H NMR spectroscopy. The labeling studies establish a regioselective pathway ...[more]

PMID: 26858471

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