The ring contraction of δ-lactones with leaving group α-substituents: A strategy for the synthesis of 2,5-disubstituted highly functionalised homochiral tetrahydrofurans

Choi SMS, Myerscough PM, Fairbanks AJ, Skead BM, Bichard CJF, Mantell SJ, Son JC, Fleet GWJ, Saunders J, Brown D

Treatment of derivatives of δ-lactones having a leaving group at C-2 with methanol in the presence of base gives methyl tetrahydrofuran-α- carboxylates in good to excellent yield with a high degree of stereocontrol of the carbon substituents at C-2 and C-5.