Kinetic studies on the reaction between substituted benzyl phosphonates and substituted benzaldehydes

Abstract

The kinetics of Wittig-Horner reaction between several middle-active phosphonates and substituted benzaldehydes, and the effect of substituents which bond on phosphonates and benzaldehydes respectively on the reaction rate have been studied. Experimental findings are consistent with intermediate formation being the rate-determining step. The substituents on phosphonates play an important part in the formation of the intermediate. Large negative entropy values provide further evidence for the rate-detemining step, and for the intermediate, which probably has a four- membered cyclic structure. © ARKAT.