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Diastereoselective syntheses of substituted cis-hydrindanones featuring sequential inter- and intramolecular Michael reactions.

ABSTRACT: The hydrindane (bicyclo[4.3.0]nonane) structural motif (1) and related cis-1-hydrindanone skeleton (2) are common substructures in many natural products. Herein, we describe efficient access to substituted cis-1-hydrindanones enabled by a sequence of Michael reactions. A copper-catalyzed intermolecular Michael addition of a cyclic silyl ketene acetal to a ?-substituted-?-alkoxycarbonyl-cyclopentenone enables construction of a quaternary center and is followed, after incorporation of an additional Michael acceptor, by a second, intramolecular addition of a nucleophilic ?-ketoester. This strategy affords stereoselective access to substituted bicyclic cis-hydrindanone ring systems containing up to three contiguous stereocenters.

SUBMITTER: Liu J

PROVIDER: S-EPMC5021295 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Diastereoselective syntheses of substituted cis-hydrindanones featuring sequential inter- and intramolecular Michael reactions.

Liu Junjia J Marsini Maurice A MA Bedell T Aaron TA Reider Paul J PJ Sorensen Erik J EJ

Tetrahedron 20160315 26

The hydrindane (bicyclo[4.3.0]nonane) structural motif (1) and related cis-1-hydrindanone skeleton (2) are common substructures in many natural products. Herein, we describe efficient access to substituted cis-1-hydrindanones enabled by a sequence of Michael reactions. A copper-catalyzed intermolecular Michael addition of a cyclic silyl ketene acetal to a β-substituted-α-alkoxycarbonyl-cyclopentenone enables construction of a quaternary center and is fol ...[more]

PMID: 27642195

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