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Desymmetrization of cyclic 1,3-diketones via Ir-catalyzed hydrogenation: an efficient approach to cyclic hydroxy ketones with a chiral quaternary carbon.

ABSTRACT: We herein report an efficient method to synthesize cyclic hydroxy ketones with a chiral quaternary center. Catalyzed by an Ir/f-ampha complex, cyclic ?,?-disubstituted 1,3-diketones were hydrogenated, giving mono-reduced products with both high enantioselectivities and diastereoselectivities. In addition, C[double bond, length as m-dash]C and C[triple bond, length as m-dash]C bonds could survive in this catalytic system. This method was applied in the preparation of (+)-estrone. No diols were observed in this chemical transformation. The enantiomeric and diastereomeric induction were achieved as a result of steric hindrance.

SUBMITTER: Gong Q

PROVIDER: S-EPMC6601421 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Desymmetrization of cyclic 1,3-diketones via Ir-catalyzed hydrogenation: an efficient approach to cyclic hydroxy ketones with a chiral quaternary carbon.

Gong Quan Q Wen Jialin J Zhang Xumu X

Chemical science 20190521 25

We herein report an efficient method to synthesize cyclic hydroxy ketones with a chiral quaternary center. Catalyzed by an Ir/f-ampha complex, cyclic α,α-disubstituted 1,3-diketones were hydrogenated, giving mono-reduced products with both high enantioselectivities and diastereoselectivities. In addition, C[double bond, length as m-dash]C and C[triple bond, length as m-dash]C bonds could survive in this catalytic system. This method was applied in the preparation of (+)-estrone. No diols were ob ...[more]

PMID: 31341590

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