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Rhodium-catalyzed asymmetric hydrogenation of unprotected NH imines assisted by a thiourea.

ABSTRACT: Asymmetric hydrogenation of unprotected NH imines catalyzed by rhodium/bis(phosphine)-thiourea provided chiral amines with up to 97% yield and 95% ee. (1)H?NMR studies, coupled with control experiments, implied that catalytic chloride-bound intermediates were involved in the mechanism through a dual hydrogen-bonding interaction. Deuteration experiments proved that the hydrogenation proceeded through a pathway consistent with an imine.

SUBMITTER: Zhao Q

PROVIDER: S-EPMC5989712 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Rhodium-catalyzed asymmetric hydrogenation of unprotected NH imines assisted by a thiourea.

Zhao Qingyang Q Wen Jialin J Tan Renchang R Huang Kexuan K Metola Pedro P Wang Rui R Anslyn Eric V EV Zhang Xumu X

Angewandte Chemie (International ed. in English) 20140618 32

Asymmetric hydrogenation of unprotected NH imines catalyzed by rhodium/bis(phosphine)-thiourea provided chiral amines with up to 97% yield and 95% ee. (1)H NMR studies, coupled with control experiments, implied that catalytic chloride-bound intermediates were involved in the mechanism through a dual hydrogen-bonding interaction. Deuteration experiments proved that the hydrogenation proceeded through a pathway consistent with an imine. ...[more]

PMID: 24939397

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