Synthesis of 5-alkyl-4-bromo-5-hydroxy-2 (5H)-furanones and 5-alkylidene-4-bromo-2(5H)-furanones

Article abstract of DOI:10.1016/S0040-4039(00)97887-0

Treatment of monoalkylsubstituted allenic esters 4 with NBS and water in the darkness yields β-bromo-α,β-butenolides 5, that are easily transformed into 5-alkyl-4-bromo-5-hydroxy-2(5H)-furanones 8 and 5-alkylidene-4-bromo-2-(5H)-furanones 2.