 At -60 ̊C the reaction of 1 and 2 afforded evenly to the lactone (3), the carbonyl addition product which underwent conversion on treatment with acid.The free acid (4) was obtained when the latter was cleaved reductively with zinc and alkali.Cyclization of the product occurred when treated with ZnCl2 in acetic acid anhydride and gave the compound 6-acetoxy-3-MC (5).