KINETICS OF THE REACTION OF SODIUM THIOPHENOXIDE WITH METHYL 3-ARYLPROPYNOATES IN DMF

Methyl 3-arylpropynoates react with thiophenoxide ion in DMF containin g 8.5% MeOH to give an isomeric mixture of Z- and E-methyl 3-aryl-3-ph enylthio-propenoates. II has been found that the rate constant depends on the methanol concentration indicating a third order reaction. The plot of log k(3) values versus Hammett sigma constants varies between 0.42 to 0.77 depending on temperature. The activation parameters and r ho values indicate that the reaction proceeds via a converted mechanis m.