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Enantioselective total synthesis of (+)-reserpine.

ABSTRACT: A catalytic, enantioselective synthesis of (+)-reserpine is reported. The route features a highly diastereoselective, chiral catalyst-controlled formal aza-Diels-Alder reaction between a 6-methoxytryptamine-derived dihydro-?-carboline and an enantioenriched ?-substituted enone to form a key tetracyclic intermediate. This approach addresses the challenge of setting the C3 stereogenic center by using catalyst control. Elaboration of the tetracycle to (+)-reserpine includes an intramolecular aldol cyclization and a highly diastereoselective hydrogenation of a sterically hindered enoate.

SUBMITTER: Rajapaksa NS

PROVIDER: S-EPMC3578295 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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Enantioselective total synthesis of (+)-reserpine.

Rajapaksa Naomi S NS McGowan Meredeth A MA Rienzo Matthew M Jacobsen Eric N EN

Organic letters 20130118 3

A catalytic, enantioselective synthesis of (+)-reserpine is reported. The route features a highly diastereoselective, chiral catalyst-controlled formal aza-Diels-Alder reaction between a 6-methoxytryptamine-derived dihydro-β-carboline and an enantioenriched α-substituted enone to form a key tetracyclic intermediate. This approach addresses the challenge of setting the C3 stereogenic center by using catalyst control. Elaboration of the tetracycle to (+)-reserpine includes an intramolecular aldol ...[more]

PMID: 23331099

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