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Rhodium-catalyzed asymmetric hydrogenation of ?-cyanocinnamic esters with the assistance of a single hydrogen bond in a precise position.

ABSTRACT: With the assistance of hydrogen bonds, the first asymmetric hydrogenation of ?-cyanocinnamic esters is developed, affording chiral ?-cyano esters with excellent enantioselectivities (up to 99% ee). This novel methodology provides an efficient and concise synthetic route to chiral GABA-derivatives such as (S)-Pregabalin, (R)-Phenibut, (R)-Baclofen. Interestingly, in this system, the catalyst with a single H-bond donor performs better than that with double H-bond donors, which is a novel discovery in the metalorganocatalysis area.

SUBMITTER: Li X

PROVIDER: S-EPMC5890790 | biostudies-literature |

REPOSITORIES: biostudies-literature

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