where used for C-alkylation to achieve the intermediates of biologically active molecules . Herein we treated O-protected oxime 2l with dichlorocarbene and obtained the product 9a, minor product, and major product 9b is debenzylated, whose cyclopropane proton and NH are combined shows as mulltplet . The cleavage of benzyloxy group due to excess of reagent in reaction medium, which is consistent with reported methods where unprotected oxime under similar condition gives nitrile .