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Enantioselective, Copper-Catalyzed Alkynylation of Ketimines To Deliver Isoquinolines with ?-Diaryl Tetrasubstituted Stereocenters.

ABSTRACT: An enantioselective, copper-catalyzed alkynylation of cyclic ?,?-diaryl ketiminium ions has been developed to deliver isoquinoline products with diaryl, tetrasubstituted stereocenters. The success of this reaction relied on identification of Ph-PyBox as the optimal ligand, i-Pr2NEt as the base, and CHCl3 as the solvent. A broad scope and functional group tolerance were observed. Notably, the use of both aryl and silyl acetylenes results in high yields and enantioselectivities. Mechanistic experiments are consistent with a dimeric or higher order catalyst.

SUBMITTER: Dasgupta S

PROVIDER: S-EPMC5161116 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Enantioselective, Copper-Catalyzed Alkynylation of Ketimines To Deliver Isoquinolines with α-Diaryl Tetrasubstituted Stereocenters.

Dasgupta Srimoyee S Liu Jixin J Shoffler Clarissa A CA Yap Glenn P A GP Watson Mary P MP

Organic letters 20161116 23

An enantioselective, copper-catalyzed alkynylation of cyclic α,α-diaryl ketiminium ions has been developed to deliver isoquinoline products with diaryl, tetrasubstituted stereocenters. The success of this reaction relied on identification of Ph-PyBox as the optimal ligand, i-Pr<sub>2</sub>NEt as the base, and CHCl<sub>3</sub> as the solvent. A broad scope and functional group tolerance were observed. Notably, the use of both aryl and silyl acetylenes results in high yields and enantioselectiviti ...[more]

PMID: 27934382

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