NOTE
Decarboxylation of 6-Nitrobenzisoxazole-3-Carboxylate Ion in Dichloromethane:
The Effects of Surfactant Structure ation of 1 is relatively simple; with or without added water bulky groups at the ammonium ion center increase catalysis, probably by making it The spontaneous decarboxylation of the 6-nitrobenzisoxazoledifficult for the ions to pack around a microdroplet of water in a reverse 3-carboxylate ion, 1, in dichloromethane is catalyzed by amine micelle. In that event they form small ion clusters which are more catalytioxide surfactants, C 14 H 29 N / R 2 O 0 , R ร
Me, n-Pr, and less strongly cally effective than micelles (6, 7). by betaine sulfonate surfactants. The amine oxides are sufficiently basic in the solvent to deprotonate the carboxylic acid. Solutions of the amine oxides tolerate water which, as with cationic surfactants, MATERIALS AND METHODS sharply inhibits reaction, but solutions of C 14 H 29 N / R 2 SO 0 3 , R ร
Me, n-Pr, will not tolerate water. The water inhibitions are proba-Materials bly due to formation of ''water-pool'' reverse micelles which are catalytically less effective than small surfactant clusters. แญง 1996
The preparation and purification of 1, and the sulfobetaine surfactants have been described (1,11). The amine oxides were prepared by heating Academic Press, Inc.