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Enantioselective copper-catalyzed alkynylation of benzopyranyl oxocarbenium ions.

ABSTRACT: We have developed highly enantioselective, copper-catalyzed alkynylations of benzopyranyl acetals. By using a copper(I) catalyst equipped with a chiral bis(oxazoline) ligand, high yields and enantioselectivities are achieved in the alkynylation of widely available, racemic isochroman and chromene acetals to deliver ?-chiral oxygen heterocycles. This method demonstrates that chiral organometallic nucleophiles can be successfully used in enantioselective additions to oxocarbenium ions.

SUBMITTER: Srinivas HD

PROVIDER: S-EPMC4822504 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Enantioselective copper-catalyzed alkynylation of benzopyranyl oxocarbenium ions.

Srinivas Harathi D HD Maity Prantik P Yap Glenn P A GP Watson Mary P MP

The Journal of organic chemistry 20150407 8

We have developed highly enantioselective, copper-catalyzed alkynylations of benzopyranyl acetals. By using a copper(I) catalyst equipped with a chiral bis(oxazoline) ligand, high yields and enantioselectivities are achieved in the alkynylation of widely available, racemic isochroman and chromene acetals to deliver α-chiral oxygen heterocycles. This method demonstrates that chiral organometallic nucleophiles can be successfully used in enantioselective additions to oxocarbenium ions. ...[more]

PMID: 25847687

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