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Organocatalytic Highly Enantioselective Tandem Michael-Knoevenagel Reaction for the Synthesis of Substituted Thiochromanes.

ABSTRACT: Enantioenriched tetrasubstituted thiochromanes have been synthesized using a tandem Michael addition-Knoevenagel reaction between 2-mercaptobenzaldehydes and benzylidenemalonates with a 9-epi-aminoquinine thiourea derivative as the catalyst. Steric and electron effects were found to affect profoundly the enantioselectivity and diastereoselectivity of the reaction.

SUBMITTER: Dodda R

PROVIDER: S-EPMC2350192 | biostudies-literature | 2008 Mar

REPOSITORIES: biostudies-literature

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Organocatalytic Highly Enantioselective Tandem Michael-Knoevenagel Reaction for the Synthesis of Substituted Thiochromanes.

Dodda Rajasekhar R Mandal Tanmay T Zhao Cong-Gui CG

Tetrahedron letters 20080301 12

Enantioenriched tetrasubstituted thiochromanes have been synthesized using a tandem Michael addition-Knoevenagel reaction between 2-mercaptobenzaldehydes and benzylidenemalonates with a 9-epi-aminoquinine thiourea derivative as the catalyst. Steric and electron effects were found to affect profoundly the enantioselectivity and diastereoselectivity of the reaction. ...[more]

PMID: 19295905

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