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A torquoselective 6? electrocyclization approach to reserpine alkaloids.

ABSTRACT: A highly torquoselective thermal triene 6? electrocyclization controls the relative stereochemistry between the C3 and C18 stereocenters of the dodecahydroindolo[2,3-a]benzo[g]quinolizine skeleton of reserpine-type alkaloids. Employing a tandem cross-coupling/electrocyclization protocol allowed us to form the requisite triene and ensure its subsequent cyclization. A novel low-temperature dibromoketene acetal Claisen rearrangement established the requisite exocyclic dienylbromide precursor for the palladium-catalyzed cross-coupling reaction.

SUBMITTER: Barcan GA

PROVIDER: S-EPMC3488149 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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A torquoselective 6π electrocyclization approach to reserpine alkaloids.

Barcan Gregg A GA Patel Ashay A Houk K N KN Kwon Ohyun O

Organic letters 20121005 21

A highly torquoselective thermal triene 6π electrocyclization controls the relative stereochemistry between the C3 and C18 stereocenters of the dodecahydroindolo[2,3-a]benzo[g]quinolizine skeleton of reserpine-type alkaloids. Employing a tandem cross-coupling/electrocyclization protocol allowed us to form the requisite triene and ensure its subsequent cyclization. A novel low-temperature dibromoketene acetal Claisen rearrangement established the requisite exocyclic dienylbromide precursor for th ...[more]

PMID: 23039026

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