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A metal-catalyzed new approach for ?-alkynylation of cyclic amines.

ABSTRACT: The first catalytic ?-alkynylation of cyclic amines with the help of the N-propargylic group to afford 2-(1-alkynyl) N-allylic cyclic amines with an exclusive E-stereoselectivity for the in situ formed C[double bond, length as m-dash]C bond has been realized. Based on mechanistic studies, it is proven that the reaction proceeds through metal-mediated anti-1,5-hydride transfer forming an iminonium intermediate, which accepts the addition of the in situ generated 1-alkynyl metal species. The synthetic application has also been demonstrated.

SUBMITTER: Cui Y

PROVIDER: S-EPMC6369436 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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A metal-catalyzed new approach for α-alkynylation of cyclic amines.

Cui Yifan Y Lin Weilong W Ma Shengming S

Chemical science 20181126 6

The first catalytic α-alkynylation of cyclic amines with the help of the N-propargylic group to afford 2-(1-alkynyl) N-allylic cyclic amines with an exclusive E-stereoselectivity for the in situ formed C[double bond, length as m-dash]C bond has been realized. Based on mechanistic studies, it is proven that the reaction proceeds through metal-mediated anti-1,5-hydride transfer forming an iminonium intermediate, which accepts the addition of the in situ ge ...[more]

PMID: 30842847

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