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Easy To Synthesize, Robust Organo-osmium Asymmetric Transfer Hydrogenation Catalysts.

ABSTRACT: Asymmetric transfer hydrogenation (ATH) is an important process in organic synthesis for which the Noyori-type Ru(II) catalysts [(arene)Ru(Tsdiamine)] are now well established and widely used. We now demonstrate for the first time the catalytic activity of the osmium analogues. X-ray crystal structures of the 16-electron Os(II) catalysts are almost identical to those of Ru(II). Intriguingly the precursor complex was isolated as a dichlorido complex with a monodentate amine ligand. The Os(II) catalysts are readily synthesised (within 1?h) and exhibit excellent enantioselectivity in ATH reactions of ketones.

SUBMITTER: Coverdale JP

PROVIDER: S-EPMC4832837 | biostudies-other | 2015 May

REPOSITORIES: biostudies-other

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Easy To Synthesize, Robust Organo-osmium Asymmetric Transfer Hydrogenation Catalysts.

Coverdale James P C JP Sanchez-Cano Carlos C Clarkson Guy J GJ Soni Rina R Wills Martin M Sadler Peter J PJ

Chemistry (Weinheim an der Bergstrasse, Germany) 20150408 22

Asymmetric transfer hydrogenation (ATH) is an important process in organic synthesis for which the Noyori-type Ru(II) catalysts [(arene)Ru(Tsdiamine)] are now well established and widely used. We now demonstrate for the first time the catalytic activity of the osmium analogues. X-ray crystal structures of the 16-electron Os(II) catalysts are almost identical to those of Ru(II). Intriguingly the precursor complex was isolated as a dichlorido complex with a monodentate amine ligand. The Os(II) cat ...[more]

PMID: 25853228

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