Bulky Diarylammonium Arenesulfonates as Selective Esterification Catalysts

diarylammonium arenesulfonates - esterification -

Significance

Polymer-supported bulky diarylammonium arenesulfonate catalyst was found to promote the direct ester condensation reaction of 4-phenylbutyric acid with 1-octanol to give 1-octyl 4-phenylbutyrate in over 99% yield. The catalyst was readily recovered and reused by filtration. The recycling of the catalyst was repeated nine times during which no loss of catalytic activity was observed.

Comment

Diarylammonium arenesulfonates were developed as a novel entry of the catalyst promoting direct esterification of carboxylic acids with alcohols. The main part of this paper describes the solution-phase esterification with the new catalyst. Heterogeneous switching of the catalysis makes this paper substantially stronger.