Enantioselective preparation of .beta.-alkyl-.gamma.-butyrolactones from functionalized ketene dithioacetals

• Published in: Journal of organic chemistry Vol. 58; no. 10; pp. 2725 - 2737
• Main Authors: Koch, Stacie S. Canan, Chamberlin, A. Richard
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 01.05.1993; Amer Chemical Soc
• Subjects: Chemistry; Chemistry, Organic; Exact sciences and technology; Heterocyclic compounds; Heterocyclic compounds with o, s, se, te hetero atom and condensed derivatives; Organic chemistry; Physical Sciences; Preparations and properties; Science & Technology; STRUCTURALLY SIMPLE ALPHA,BETA-BUTENOLIDES; STEREOSELECTIVE ALDOL CONDENSATIONS; ORGANIC-SYNTHESIS; ASYMMETRIC-SYNTHESIS; ABSOLUTE-CONFIGURATION; L-GLUTAMIC ACID; STREPTOMYCIN BIOSYNTHESIS; SYNTHETIC MICROBIAL CHEMISTRY; DEHYDROGENASE CATALYZED OXIDATIONS; RING-CLOSURE; Five membered ring; Dithioacetal; Chiral auxiliary; Cyclization; Asymmetric synthesis; Deprotection; Lactone; Oxygen heterocycle; Thioketenes; Alkylation
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo00062a013

An efficient and general enantioselective synthesis of beta-alkyl-gamma-butyrolactones has been developed. The key step of this procedure is an oxazolidinone-directed alkylation of a lithiated ketene dithioacetal that proceeds with excellent regiochemical control and high diastereofacial selectivity. Reductive removal of the chiral auxiliary followed by acid-induced cyclization of the resultant hydroxy ketene dithioacetal gives the enantiomerically pure beta-alkyl-gamma-butyrolactone.