Abstract The reaction of ethyl chloroglyoxylate phenyl hydrazone and diphenyl hydrazonyl chloride with several carboalkoxymethylene triphenylphosphoranes has been examined. The products isolated correspond to N-phenyl-3-carboalkoxy-5-alkoxy substituted pyrazoles. The mechanism advanced to account for the formation of the products involves the stepwise addition of a nitrile imine intermediate with the Wittig reagent.
