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Iridium-catalyzed asymmetric hydrogenation of racemic ?-substituted lactones to chiral diols.

ABSTRACT: We report a protocol for the highly efficient iridium-catalyzed asymmetric hydrogenation of racemic ?-substituted lactones via dynamic kinetic resolution. Using Ir-SpiroPAP (R)-1d as a catalyst, a wide range of chiral diols were prepared in a high yield (80-95%) with a high enantioselectivity (up to 95% ee) under mild reaction conditions. This protocol was used for enantioselective syntheses of (-)-preclamol and a chiral 2,5-disubstituted tetrahydropyran.

SUBMITTER: Yang XH

PROVIDER: S-EPMC5396509 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Iridium-catalyzed asymmetric hydrogenation of racemic α-substituted lactones to chiral diols.

Yang Xiao-Hui XH Yue Hai-Tao HT Yu Na N Li Yi-Pan YP Xie Jian-Hua JH Zhou Qi-Lin QL

Chemical science 20161115 3

We report a protocol for the highly efficient iridium-catalyzed asymmetric hydrogenation of racemic α-substituted lactones via dynamic kinetic resolution. Using Ir-SpiroPAP (R)-1d as a catalyst, a wide range of chiral diols were prepared in a high yield (80-95%) with a high enantioselectivity (up to 95% ee) under mild reaction conditions. This protocol was used for enantioselective syntheses of (-)-preclamol and a chiral 2,5-disubstituted tetrahydropyran. ...[more]

PMID: 28451302

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