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Catalytic enantioselective carboannulation with allylsilanes.

ABSTRACT: The first catalytic asymmetric carboannulation with allylsilanes is presented. The enantioselective [3+2] annulation is catalyzed using a scandium(III)/indapybox complex with tetrakis-[3,5-bis(trifluoromethyl)phenyl]-borate (BArF) to enhance catalytic activity and control stereoselectivity. Functionalized cyclopentanes containing a quaternary carbon center are derived from alkylidene oxindole, coumarin, and malonate substrates with high stereoselectivity. The enantioselective 1,4-conjugate addition and enantioselective lactone formation (by trapping of the ?-silyl carbocation) is also described.

SUBMITTER: Ball-Jones NR

PROVIDER: S-EPMC4795922 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

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Catalytic enantioselective carboannulation with allylsilanes.

Ball-Jones Nicolas R NR Badillo Joseph J JJ Tran Ngon T NT Franz Annaliese K AK

Angewandte Chemie (International ed. in English) 20140713 36

The first catalytic asymmetric carboannulation with allylsilanes is presented. The enantioselective [3+2] annulation is catalyzed using a scandium(III)/indapybox complex with tetrakis-[3,5-bis(trifluoromethyl)phenyl]-borate (BArF) to enhance catalytic activity and control stereoselectivity. Functionalized cyclopentanes containing a quaternary carbon center are derived from alkylidene oxindole, coumarin, and malonate substrates with high stereoselectivity. The enantioselective 1,4-conjugate addit ...[more]

PMID: 25045133

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