Quaternary Pyridinium Ketoximes - New Efficient Micellar Hydrolytic Catalysts

Abstract

A series of quaternized alkyl pyridyl ketoximes was synthesized and tested as micellar hydrolytic catalysts. 2- And 4-[1-(hydroxyimino)tridecyl]-1-methylpyridinium bromides were surprisingly efficient, most probably due to the location of their nucleophilic hydroxyimino group below the micellar surface. Absorbance of the reaction mixture vs time plots exhibited remarkable positive deviation from the first-order kinetics when hydrolysis of 4-nitrophenyl phosphates was catalyzed by 1-dodecyl-3-[1-(hydroxyimino)ethyl]- or 3-[1-(hydroxyimino)tridecyl]-1-methylpyridinium bromide.