Hydrolysis of Esters with Polymer Sulfonic Acid

IV. Hydrolysis of Aromatic Esters with Polymer Sulfonic Acids

Abstract

The hydrolysis of aromatic esters with various polymer sulfonic acids was carried out. For the hydrolysis of methyl benzoate in water, polystyrenesulfonic acid (PS-S) was a more effec-tive catalyst than hydrochloric acid, but an addition of acetone reduced the catalytic efficiency. The catalytic effect of polyvinylacetal sulfonic acid, polyvinylsulfonic acid and vinylsulfonic acid vinylalcohol copolymer were nearly the same as that of hydrochloric acid. Also for the hydrolysis of methyl o-and p-hydroxybenzoates in water PS-S was more effective than hydrochloric acid; these two esters showed somewhat different behavior by the hydrolysis. In aqueous acetone the substituents such as p-and o-hydroxy, p-nitro and p-chloro showed little difference in the catalytic effect of polymer sulfonic acids. Partial neutralization of PS-S with quaternary ammonium hydroxides reduced the catalytic effect of the remaining free sulfonic acid groups for the hydrolysis of the benzoates. Hydrolysis of some other esters with ring structure was also studied.