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Gold(I)-catalyzed enantioselective ring expansion of allenylcyclopropanols.

ABSTRACT: The asymmetric gold(I)-catalyzed ring expansion of 1-allenylcyclopropanols is described. The method provides synthetically valuable cyclobutanones with a vinyl-substituted quaternary stereogenic center in high enantioselectivities and yields. The method shows a broad substrate scope, tolerating protected alcohols and amines, alkenes, unsaturated esters, and acetals. The reaction is easily adjustable to large-scale synthesis, leading to product formation without significant loss of selectivity or yield with only 0.5 mol% catalyst loading.

SUBMITTER: Kleinbeck F

PROVIDER: S-EPMC2740622 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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Gold(I)-catalyzed enantioselective ring expansion of allenylcyclopropanols.

Kleinbeck Florian F Toste F Dean FD

Journal of the American Chemical Society 20090701 26

The asymmetric gold(I)-catalyzed ring expansion of 1-allenylcyclopropanols is described. The method provides synthetically valuable cyclobutanones with a vinyl-substituted quaternary stereogenic center in high enantioselectivities and yields. The method shows a broad substrate scope, tolerating protected alcohols and amines, alkenes, unsaturated esters, and acetals. The reaction is easily adjustable to large-scale synthesis, leading to product formation without significant loss of selectivity or ...[more]

PMID: 19530649

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