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Development of the Regiodivergent Asymmetric Prenylation of 3-Substituted Oxindoles.

ABSTRACT: This paper describes our efforts to design a Pd-catalyzed asymmetric prenylation of 3-substituted oxindoles that affords access to both the linear and reverse-prenylated products. Both 3-alkyl- and 3-aryloxindoles performed well under our optimized reaction conditions. The regiodivergent alkylation of monoterpene-derived electrophiles using this methodology was also investigated. The utility of this methodology in natural product synthesis was demonstrated through the efficient total syntheses of four Flustra alkaloids, which also allowed the absolute stereochemistry of the prenylated oxindole products to be assigned. Surprisingly, the same enantiomer of ligand produced linear and branched regioisomers of opposite chirality.

SUBMITTER: Trost BM

PROVIDER: S-EPMC5530868 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Development of the Regiodivergent Asymmetric Prenylation of 3-Substituted Oxindoles.

Trost Barry M BM Chan Walter H WH Malhotra Sushant S

Chemistry (Weinheim an der Bergstrasse, Germany) 20170306 18

This paper describes our efforts to design a Pd-catalyzed asymmetric prenylation of 3-substituted oxindoles that affords access to both the linear and reverse-prenylated products. Both 3-alkyl- and 3-aryloxindoles performed well under our optimized reaction conditions. The regiodivergent alkylation of monoterpene-derived electrophiles using this methodology was also investigated. The utility of this methodology in natural product synthesis was demonstrated through the efficient total syntheses o ...[more]

PMID: 28141896

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