METHANOLYSIS OF ORTHO-FORMYLBENZENESULFONATES AND PARA-FORMYLBENZENESULFONATES IN BASIC-MEDIA - EVIDENCE FOR THE INTRAMOLECULAR NUCLEOPHILIC CATALYSIS BY THE CARBONYL GROUP

Methanolysis of p-methoxyphenyl 2-formylbenzenesulfonate, in the prese nce of anhydrous potassium carbonate at ambient temperature gives the dimethyl acetal of 2-formylbenzenesulfonic acid in excellent yield. p- Methoxyphenyl 4-formylbenzenesulfonate under identical conditions rema ins unaffected. These results provide evidence for the catalytic invol vement of the neighbouring aldehyde carbonyl group and operation of in tramolecular nucleophilic catalysis during the nucleophilic substituti on at sulfonyl sulfur.