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Lewis acid mediated (3 + 2) cycloadditions of donor-acceptor cyclopropanes with heterocumulenes.

ABSTRACT: Isocyanates, isothiocyanates, and carbodiimides are effective substrates in (3 + 2) cycloadditions with donor-acceptor cyclopropanes for the synthesis of five-membered heterocycles. These reactions exhibit a broad substrate scope, high yields, and well-defined chemoselectivity. Discussed herein are the implications of Lewis acid choice on the stereochemical outcome and the reaction mechanism.

SUBMITTER: Goldberg AF

PROVIDER: S-EPMC3490221 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Lewis acid mediated (3 + 2) cycloadditions of donor-acceptor cyclopropanes with heterocumulenes.

Goldberg Alexander F G AF O'Connor Nicholas R NR Craig Robert A RA Stoltz Brian M BM

Organic letters 20121009 20

Isocyanates, isothiocyanates, and carbodiimides are effective substrates in (3 + 2) cycloadditions with donor-acceptor cyclopropanes for the synthesis of five-membered heterocycles. These reactions exhibit a broad substrate scope, high yields, and well-defined chemoselectivity. Discussed herein are the implications of Lewis acid choice on the stereochemical outcome and the reaction mechanism. ...[more]

PMID: 23046060

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