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Catalytic asymmetric methallylation of ketones with an (H8-BINOLate)Ti-based catalyst.

ABSTRACT: The first catalytic asymmetric methallylation of ketones is reported. The catalyst, which is generated from titanium tetraisopropoxide, H8-BINOL, 2-propanol, and tetramethallylstannane, reacts with ketones in acetonitrile to afford tertiary homoallylic alcohols in fair to excellent yields (55-99%) and fair to high enantioselectivities (46-90%). Ozonolysis of the resulting products provides access to chiral beta-hydroxy ketones, which are not readily prepared from direct asymmetric aldol reaction of acetone with ketones.

SUBMITTER: Kim JG

PROVIDER: S-EPMC2615050 | biostudies-literature | 2006 Sep

REPOSITORIES: biostudies-literature

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Catalytic asymmetric methallylation of ketones with an (H8-BINOLate)Ti-based catalyst.

Kim Jeung Gon JG Camp Elizabeth H EH Walsh Patrick J PJ

Organic letters 20060901 20

The first catalytic asymmetric methallylation of ketones is reported. The catalyst, which is generated from titanium tetraisopropoxide, H8-BINOL, 2-propanol, and tetramethallylstannane, reacts with ketones in acetonitrile to afford tertiary homoallylic alcohols in fair to excellent yields (55-99%) and fair to high enantioselectivities (46-90%). Ozonolysis of the resulting products provides access to chiral beta-hydroxy ketones, which are not readily prepared from direct asymmetric aldol reaction ...[more]

PMID: 16986913

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