SYNTHESIS AND PHOTOCHEMICAL-REACTION OF N,N-BIS[2-(CINNAMOYLOXY)ETHYL] AMMONIUM-SALTS

Some dicinnamates containing quaternary ammonium salt were synthesized by the quaterni-zation of N-methylbis[2-(cinnamoyloxy)ethyl]amine with various alkyl bromides. The photochemical behavior of the obtained compounds was evaluated in water or some organic solvents. The rate of photochemical reaction of the dicinnamates obeyed second order kinetics on the initial stage, and it was found that the reaction proceeded quantitatively by the photo-irradiation for long time. The photochemical reactivity was also strongly affected by the kind of reaction media. That is, the rate of bis[2-(cinnamoyloxy) ethyl]dimethylam- monium bromide (3 a) in water was about three times higher than that of 3 a in methanol, and the rate in diehloromethane was two times higher than that in methanol. However, the rate of 3 a was not affected by the kind of substituent on the ammonium salt. Furthermore, it was found that the dieinnamates containing quaternary ammonium salt have higher photochemical reactivity than the corresponding hydrophobic compound 1, 5-pentanediol dicinnamate. The photochemical reversion of the resulting photoproduct was also studied in water. As a result, although the photodimerization was proceeded quantitatively by irradiation with 313 nm light, the extent of photoreverse reaction by irradiation with 254 nm light was about 20%. © 1990, The Chemical Society of Japan. All rights reserved.