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Stereodivergent Metal-Catalyzed Allene Cycloisomerizations.

ABSTRACT: Metal-catalyzed allene cycloisomerizations provide rapid entry into five-membered carbocyclic frameworks, a common motif in natural products and pharmaceuticals. While both Au(I) and Pd(0)-catalyzed allene cycloisomerizations give 5-endo-dig cyclization, Pd prefers the syn diastereomer in contrast to the anti isomer observed with Au. The change in stereoselectivity is proposed to arise from buildup of A^1,3 strain during the key carbopalladation step to furnish the cycloisomerized products in moderate to good dr with yields comparable to Au(I) catalysts.

SUBMITTER: Reeves RD

PROVIDER: S-EPMC8249080 | biostudies-literature |

REPOSITORIES: biostudies-literature

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