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Asymmetric Redox-Annulation of Cyclic Amines.

ABSTRACT: Cyclic amines such as 1,2,3,4-tetrahydroisoquinoline undergo regiodivergent annulation reactions with 4-nitrobutyraldehydes. These redox-neutral transformations enable the asymmetric synthesis of highly substituted polycyclic ring systems in just two steps from commercial materials. The utility of this process is illustrated in a rapid synthesis of (-)-protoemetinol. Computational studies provide mechanistic insights and implicate the elimination of acetic acid from an ammonium nitronate intermediate as the rate-determining step.

SUBMITTER: Kang Y

PROVIDER: S-EPMC4599696 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Asymmetric Redox-Annulation of Cyclic Amines.

Kang YoungKu Y Chen Weijie W Breugst Martin M Seidel Daniel D

The Journal of organic chemistry 20151001 19

Cyclic amines such as 1,2,3,4-tetrahydroisoquinoline undergo regiodivergent annulation reactions with 4-nitrobutyraldehydes. These redox-neutral transformations enable the asymmetric synthesis of highly substituted polycyclic ring systems in just two steps from commercial materials. The utility of this process is illustrated in a rapid synthesis of (-)-protoemetinol. Computational studies provide mechanistic insights and implicate the elimination of acetic acid from an ammonium nitronate interme ...[more]

PMID: 26348653

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