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Dual catalysis in enantioselective oxidopyrylium-based [5 + 2] cycloadditions.

ABSTRACT: A new method for effecting catalytic enantioselective intramolecular [5 + 2] cycloadditions based on oxidopyrylium intermediates is reported. The dual catalyst system consists of a chiral primary aminothiourea and a second achiral thiourea. Experimental evidence points to a new type of cooperative catalysis with each species being necessary to generate a reactive pyrylium ion pair that undergoes subsequent cycloaddition with high enantioselectivity.

SUBMITTER: Burns NZ

PROVIDER: S-EPMC3173575 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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Dual catalysis in enantioselective oxidopyrylium-based [5 + 2] cycloadditions.

Burns Noah Z NZ Witten Michael R MR Jacobsen Eric N EN

Journal of the American Chemical Society 20110825 37

A new method for effecting catalytic enantioselective intramolecular [5 + 2] cycloadditions based on oxidopyrylium intermediates is reported. The dual catalyst system consists of a chiral primary aminothiourea and a second achiral thiourea. Experimental evidence points to a new type of cooperative catalysis with each species being necessary to generate a reactive pyrylium ion pair that undergoes subsequent cycloaddition with high enantioselectivity. ...[more]

PMID: 21848300

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