187. “Synthesis of cis and trans Whisky and Cognac lactones by the regiocontrolled alkylation of 2-(trimethylsiloxy)furan”
     Jefford, C.W.; Sledeski, A.W.; Boukouvalas, J.
     Helv. Chim. Acta 1989, 72, 1362-1370.

The racemic cis- and trans-5-butyltetrahydro-4-methylfuran-2-ones ( = whisky lactones) and their higher homologues tetrahydro-4-methyl-5-pentylfuran-2-ones ( = cognac lactones) have been prepared in 2–3 steps from 2-(trimethylsiloxy)furan. Regioselective alkylation of the latter afforded the 5-butyl- and 5-pentylfuran-2(5H)-ones which served as precursors for the stereocontrolled construction of either diastereoisomer of the beverage lactones. The structure and tautomerization of the diazomethane adducts of these 5-alkylfuran-2(5H)-ones are also described.

DOI : 10.1002/hlca.19890720625 

archive ouverte unige:152902