A stereoselective synthesis of methyl trans-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate

摘要

A convenient method is described for the stereoselective synthesis of methyl trans -3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate (5) via methyl 3,3-dimethyl -4,6,6,6-tetrachlorohexanoate (4) as a key intermediate, which was obtained by addition of carbon tetrachloride to methyl 3,3-dimethyl-4-pentenoate (3). Treatment of (4) with sodium methoxide in a single-vessel via methyl 4,6,6-trichloro-3,3-dimethyl-5-hexenoate (6) gave trans-rich (5) in excellent yield.