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Lewis acid-catalyzed conjugate additions of silyloxyallenes: a selective solution to the intermolecular Rauhut-Currier problem.

ABSTRACT: Silyloxyallenes serve as highly useful alpha-acylvinyl anion equivalents. These latent allenolates undergo conjugate additions to alkylidene malonates in the presence of 10 mol % Sc(OTf) 3. The reaction delivers intermolecular Rauhut-Currier products in excellent yields and regioselectivities for a wide scope of substrates. Notably, the formal cross-coupling of two different alpha,beta-unsaturated carbonyl compounds (a cross Rauhut-Currier reaction) is achieved. Preliminary investigations have demonstrated good levels of enantioselectivity for the addition of a racemic silyloxyallene with a chiral Lewis acid.

SUBMITTER: Reynolds TE

PROVIDER: S-EPMC2977949 | biostudies-literature | 2008 Jun

REPOSITORIES: biostudies-literature

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Lewis acid-catalyzed conjugate additions of silyloxyallenes: a selective solution to the intermolecular Rauhut-Currier problem.

Reynolds Troy E TE Binkley Michael S MS Scheidt Karl A KA

Organic letters 20080514 12

Silyloxyallenes serve as highly useful alpha-acylvinyl anion equivalents. These latent allenolates undergo conjugate additions to alkylidene malonates in the presence of 10 mol % Sc(OTf) 3. The reaction delivers intermolecular Rauhut-Currier products in excellent yields and regioselectivities for a wide scope of substrates. Notably, the formal cross-coupling of two different alpha,beta-unsaturated carbonyl compounds (a cross Rauhut-Currier reaction) is achieved. Preliminary investigations have d ...[more]

PMID: 18476709

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