Photo-decomposition Products of 1-Azidopyrene in Various Solvents

Abstract

1-Pyrenylnitrene formed by the photolysis of 1-azidopyrene in degassed methanol gave 1- aminopyrene and 1, 1'-azopyrene while it gave only 1, 1'-azopyrene in degassed benzene. When phenol exsisted in degassed benzene, N- (1-pyrenyl) -p-benzoquinone monoimine was formed in addition to 1-aminopyrene and 1, 1'-azopyrene.1-Aminopyrene, 1, 1'-azopyrene and a quinone imine compound were formed by the photolysis of 1-azidopyrene in phenol resin matrix. The formation of quinone imine compound was due to the reaction of 1-pyrenylnitrene with phenol group of the resin, and resulted in the insolubilization of phenol resin in alkaline water. When oxygen exsisted in the solution, 1-nitropyrene and 1, 1'-azoxypyrene were produced besides the compounds described above. The rate constants of hydrogen abstraction of 1- pyrenylnitrene from the solvents were determined from the amount of 1-aminopyrene formed by a flash photolysis of 1-azidopyrene in toluene, p-xyrene, ethylbenzene, cumene, methanol, diphenylmethane and phenol as follows; 1.1 x 10³, 1.8 X 10³, 3.7 X 10³, 1.8 x 10³, 4.0 X 10⁸, 6.0 X 10⁴, x 10⁵ (l mol^-1 sec^-1) Hydrogen of benzene was not abstracted by 1-pyrenylnitrene. N(1-P y r eny) -2, 6-dimethyl-p-benzoquinone monoimine, N- (1-pyrenyl) -2, 4-dimethyl-o-benzoquinone monoimine and N- (1-pyrenyl) -4-benzyl-o-benzoquinone monoimine were formed by the reaction of 1-pyrenylnitrene with 2, 6-xylenol, 2, 4-xylenol and p-benzylphenol, respectively.