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Highly concentrated catalytic asymmetric allylation of ketones.

ABSTRACT: [reaction: see text] We report the catalytic asymmetric allylation of ketones under highly concentrated reaction conditions with a catalyst generated from titanium tetraisopropoxide and BINOL (1:2 ratio) in the presence of isopropanol. This catalyst promotes the addition of tetraallylstannane to a variety of ketones to produce tertiary homoallylic alcohols in excellent yield (80-99%) with high enantioselectivities (79-95%). The resulting homoallylic alcohols can also be epoxidized in situ using tert-butyl hydroperoxide (TBHP) to afford cyclic epoxy alcohols in high yield (84-87%).

SUBMITTER: Wooten AJ

PROVIDER: S-EPMC2526120 | biostudies-literature | 2007 Feb

REPOSITORIES: biostudies-literature

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Highly concentrated catalytic asymmetric allylation of ketones.

Wooten Alfred J AJ Kim Jeung Gon JG Walsh Patrick J PJ

Organic letters 20070201 3

[reaction: see text] We report the catalytic asymmetric allylation of ketones under highly concentrated reaction conditions with a catalyst generated from titanium tetraisopropoxide and BINOL (1:2 ratio) in the presence of isopropanol. This catalyst promotes the addition of tetraallylstannane to a variety of ketones to produce tertiary homoallylic alcohols in excellent yield (80-99%) with high enantioselectivities (79-95%). The resulting homoallylic alcohols can also be epoxidized in situ using ...[more]

PMID: 17249767

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