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A new organocatalyzed Michael-Michael cascade reaction generates highly substituted fused carbocycles.

ABSTRACT: While beta-ketoesters are useful Michael donors, they were previously ineffective in Michael-Michael cascade reactions using alpha,beta-unsaturated aldehydes in conjunction with diphenylprolinol silyl ether organocatalysts. However, through rational modification of substrates and manipulation of the catalytic cycle, we developed an efficient Michael-Michael cascade reaction using beta-ketoesters of type 9. In this transformation, highly substituted fused carbocycles are generated in a single step in up to 87% yield and 99% ee.

SUBMITTER: McGarraugh PG

PROVIDER: S-EPMC2802209 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature

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A new organocatalyzed Michael-Michael cascade reaction generates highly substituted fused carbocycles.

McGarraugh Patrick G PG Brenner Stacey E SE

Organic letters 20091201 24

While beta-ketoesters are useful Michael donors, they were previously ineffective in Michael-Michael cascade reactions using alpha,beta-unsaturated aldehydes in conjunction with diphenylprolinol silyl ether organocatalysts. However, through rational modification of substrates and manipulation of the catalytic cycle, we developed an efficient Michael-Michael cascade reaction using beta-ketoesters of type 9. In this transformation, highly substituted fused carbocycles are generated in a single ste ...[more]

PMID: 19921792

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