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Probing the Hydrogenation of Vinyl Sulfoxides Using para-Hydrogen.

ABSTRACT: Vinyl sulfoxides are an important functional group used in a wide range of organic transformations. Here, we use [IrCl(COD)(IMes)] where IMes = 1,3-bis(2,4,6-trimethyl-phenyl)imidazole-2-ylidene and COD = cis,cis-1,5-cyclooctadiene to rapidly hydrogenate phenylvinylsulfoxide. We use para-hydrogen-induced hyperpolarization (PHIP) to follow this reaction with [IrCl(H)₂(IMes)(S(O)(Ph)(Et))₂] dominating in the later stages. Decomposition to form the reduced C-S bond cleavage product [Ir₂(H)₃(?²-H)(?²-SPh)₂(IMes)₂(S(Et)(Ph)O)] limits turnover. The related product [Ir₂(H)₄(?²-S)(IMes)₂(S(O)(CH₂Ph)₂)₂] is formed from dibenzylsulfoxide, demonstrating the wider utility of this transformation.

SUBMITTER: Tickner BJ

PROVIDER: S-EPMC6880776 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Probing the Hydrogenation of Vinyl Sulfoxides Using para-Hydrogen.

Tickner Ben J BJ Parker Rachel R RR Whitwood Adrian C AC Duckett Simon B SB

Organometallics 20191114 22

Vinyl sulfoxides are an important functional group used in a wide range of organic transformations. Here, we use [IrCl(COD)(IMes)] where IMes = 1,3-bis(2,4,6-trimethyl-phenyl)imidazole-2-ylidene and COD = cis,cis-1,5-cyclooctadiene to rapidly hydrogenate phenylvinylsulfoxide. We use para-hydrogen-induced hyperpolarization (PHIP) to follow this reaction with [IrCl(H)2(IMes)(S(O)(Ph)(Et))2] dominating in the later stages. Decomposition to form the reduced ...[more]

PMID: 31787798

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