Six optically active 4-alkyl-3-a-(1-naphthyl)ethylthiazolium salts I (n = 1, 2, 7, 11, 15, 21) were prepared by the reaction of a-(1-naphthyl)-N-(thioformyl)ethylamine with haloketones. When these optically active thiazolium salts were used as catalysts in the benzoin condensation, reasonable yield (20-30%) and moderate optical purity (47-57%) of benzoin was obtained in aqueous solution The micellar properties of (+)-I (n = 1, X = Cl) (II) in various buffer solution and asym. benzoin condensation using II as catalyst were studied. The observation of crit. micelle concentration (cmc) in various buffer solns. shows that II exists as a micelle to catalyze the benzoin condensation. The yield of benzoin up to 61% with optical purity of 23.6% was obtained in the presence of borax.

Key words: THIAZOLE P, CONDENSATION REACTION, CATALYSIS, MICELLE, NAPHTHALENE P, SURFACE CHEMISTRY, ALKANE P, CRITICAL MASS, GUM BENZOIN