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Gold(I)-catalyzed cascade cyclization of allenyl epoxides.

ABSTRACT: Cationic gold(I) phosphite catalysts activate allenes for epoxide cascade reactions. The system is tolerant of numerous functional groups (sulfones, esters, ethers, sulfonamides) and proceeds at room temperature in dichloromethane. The cyclization pathway is sensitive to the substitution pattern of the epoxide and the backbone structure of the A-ring. It is capable of producing medium-ring ethers, fused 6-5 bicyclic, and linked pyran-furan structures. The resulting cycloisomers are reminiscent of structures found in numerous polyether natural products.

SUBMITTER: Tarselli MA

PROVIDER: S-EPMC2742359 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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Gold(I)-catalyzed cascade cyclization of allenyl epoxides.

Tarselli Michael A MA Zuccarello J Lucas JL Lee Stephen J SJ Gagné Michel R MR

Organic letters 20090801 15

Cationic gold(I) phosphite catalysts activate allenes for epoxide cascade reactions. The system is tolerant of numerous functional groups (sulfones, esters, ethers, sulfonamides) and proceeds at room temperature in dichloromethane. The cyclization pathway is sensitive to the substitution pattern of the epoxide and the backbone structure of the A-ring. It is capable of producing medium-ring ethers, fused 6-5 bicyclic, and linked pyran-furan structures. The resulting cycloisomers are reminiscent o ...[more]

PMID: 19588972

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