EXPEDIENT SYNTHESIS OF (R)-PATULOLIDE-A

An efficient derivation of the title compound has been formulated from easily accessible 10-undecenoic acid(1). Thus, dodec-11-en-2-ol (3), prepared from 1, was pyranylated and subjected to bromination with NBS followed by acetolysis to furnish E)-1-acetoxy-11-(tetrahydropyranylo xy)-dodec-2-ene (5). Its hydrolysis, oxidation, and depyranylation aff orded the (2E)-hydroxy ester (9). This, on Candida rugosa lipase-catal yzed acetylation, SeO2 oxidation, hydrolysis, and Yamaguchi macrolacto nization, led to (R)-patulolide A (I) with 67.1% ee. The enantiomeric excess was improved to 97% by first resolving the alcohol 3 via porcin e pancreatic lipase catalyzed acetylation and converting the correspon ding (R)-acetate (13) to I as done above.