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Synthesis of sultam scaffolds via intramolecular oxa-Michael and diastereoselective Baylis-Hillman reactions.

ABSTRACT: A divergent synthetic approach to new sultams utilizing intramolecular oxa-Michael and Baylis-Hillman reactions of readily prepared vinyl sulfonamides and suitably protected amino alcohols, is reported. A variety of seven- and eight-membered ring sultam scaffolds were synthesized using oxa-Michael pathways, whereas both five- and six-membered rings were synthesized using Baylis-Hillman methods. Baylis-Hillman reactions proceed with good to excellent levels of diastereoselectivity, and oxa-Michael reactions leading to eight-membered ring sultams provide empirical evidence validating 8- endo-trig cyclization pathways.

SUBMITTER: Zhou A

PROVIDER: S-EPMC2742884 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature

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Synthesis of sultam scaffolds via intramolecular oxa-Michael and diastereoselective Baylis-Hillman reactions.

Zhou Aihua A Hanson Paul R PR

Organic letters 20080614 14

A divergent synthetic approach to new sultams utilizing intramolecular oxa-Michael and Baylis-Hillman reactions of readily prepared vinyl sulfonamides and suitably protected amino alcohols, is reported. A variety of seven- and eight-membered ring sultam scaffolds were synthesized using oxa-Michael pathways, whereas both five- and six-membered rings were synthesized using Baylis-Hillman methods. Baylis-Hillman reactions proceed with good to excellent levels of diastereoselectivity, and oxa-Michae ...[more]

PMID: 18553974

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