Ring expansions of beta-keto lactones with zinc carbenoids: syntheses of (+)-patulolide A and (+/-)-patulolide B.
A one-pot ring expansion/oxidation/elimination method has been developed in which beta-keto lactones are converted efficiently to alpha,beta-unsaturated-gamma-keto lactones. The reaction can be successfully applied to a variety of ring sizes. Alkene stereochemistry is dependent upon ring size and reaction conditions. The method was applied to the synthesis of (+)-patulolide A.
Ronsheim
Matthew D
MD
Department of Chemistry, University of New Hampshire, Durham, New Hampshire 03824.
Zercher
Charles K
CK
D000475:Alkenes / Q000737:chemistry*; D002384:Catalysis; D003500:Cyclization; D007202:Indicators and Reagents; D007659:Ketones / Q000737:chemistry*; D007783:Lactones / Q000138:chemical synthesis* / Q000737:chemistry*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010084:Oxidation-Reduction; D013237:Stereoisomerism; D015032:Zinc / Q000737:chemistry*
D000475:Alkenes; D007202:Indicators and Reagents; D007659:Ketones; D007783:Lactones; C049726:patulolide B; C049725:patulolide A; D015032:Zinc