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Enantioselective thiourea-catalyzed cationic polycyclizations.

ABSTRACT: A new thiourea catalyst is reported for the enantioselective cationic polycyclization of hydroxylactams. Both the yield and enantioselectivity of this transformation were found to vary strongly with the identity of a single aromatic residue on a common catalyst framework, with more expansive and polarizable arenes proving optimal. Evidence is presented for a mechanism in which stabilizing cation-pi interactions are a principal determinant of enantioselectivity.

SUBMITTER: Knowles RR

PROVIDER: S-EPMC2989498 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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Enantioselective thiourea-catalyzed cationic polycyclizations.

Knowles Robert R RR Lin Song S Jacobsen Eric N EN

Journal of the American Chemical Society 20100401 14

A new thiourea catalyst is reported for the enantioselective cationic polycyclization of hydroxylactams. Both the yield and enantioselectivity of this transformation were found to vary strongly with the identity of a single aromatic residue on a common catalyst framework, with more expansive and polarizable arenes proving optimal. Evidence is presented for a mechanism in which stabilizing cation-pi interactions are a principal determinant of enantioselectivity. ...[more]

PMID: 20369901

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