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Metal-free transfer hydrogenation of olefins via dehydrocoupling catalysis.

ABSTRACT: A major advance in main-group chemistry in recent years has been the emergence of the reactivity of main-group species that mimics that of transition metal complexes. In this report, the Lewis acidic phosphonium salt [(C6F5)3PF][B(C6F5)4] 1 is shown to catalyze the dehydrocoupling of silanes with amines, thiols, phenols, and carboxylic acids to form the Si-E bond (E = N, S, O) with the liberation of H2 (21 examples). This catalysis, when performed in the presence of a series of olefins, yields the concurrent formation of the products of dehydrocoupling and transfer hydrogenation of the olefin (30 examples). This reactivity provides a strategy for metal-free catalysis of olefin hydrogenations. The mechanisms for both catalytic reactions are proposed and supported by experiment and density functional theory calculations.

SUBMITTER: Perez M

PROVIDER: S-EPMC4121813 | biostudies-other | 2014 Jul

REPOSITORIES: biostudies-other

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Metal-free transfer hydrogenation of olefins via dehydrocoupling catalysis.

Pérez Manuel M Caputo Christopher B CB Dobrovetsky Roman R Stephan Douglas W DW

Proceedings of the National Academy of Sciences of the United States of America 20140707 30

A major advance in main-group chemistry in recent years has been the emergence of the reactivity of main-group species that mimics that of transition metal complexes. In this report, the Lewis acidic phosphonium salt [(C6F5)3PF][B(C6F5)4] 1 is shown to catalyze the dehydrocoupling of silanes with amines, thiols, phenols, and carboxylic acids to form the Si-E bond (E = N, S, O) with the liberation of H2 (21 examples). This catalysis, when performed in the presence of a series of olefins, yields t ...[more]

PMID: 25002489

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