Enantiomerically Pure Lactones. 2. Approaches to Cis or Trans Multicyclic Lactones

Article abstract of DOI:10.1021/jo01309a008

Enantiomerically pure bicyclic lactones 1-3 and tricyclic lactones 4 and 5 have been prepared by either of two procedures, each hinging upon the liquid chromatographic seperation of rationally selected diastereomeric derivatives.After seperation, the diastereomers are converted by a simple high-yield reaction sequence to the enantiomeric multiring lactones, none of which has been previously reported in optically active form. The relative strengths and weaknesses of each approach are discussed.Lactones 4 and 5 were α-methylated, these derivatives being suitable for the determination of enantiomeric purity and absolute configuration using the chiral solvating agent (S)-(+)-2,2,2-trifluoro-1-(9-anthryl)ethanol.