四苯基卟啉在苯溶液中光解产生自由基的ESR研究

INVESTIGATION ON THE FREE RADICALS PRODUCED IN THE PHOTOLYSIS OF TETRA-PHENYL-PORPHYRIN IN BENZENE SOLUTION BY ESR METHOD

用自旋捕捉-ESR方法对四苯基卟啉(H_2TPP)在苯中光解后产生的活泼自由基进行研究。当PBN存在时,光解中可给出6重ESR峰,表明自旋加合物为[HTPP-PBN]。而氧和碘化物的猝灭作用可知H_2TPP的光解是经由三重激发态途径进行的。而PBN的光敏分解则是由尚未转入三重态的H_2TPP所引起的。

The active radicals produced from the photolysis of tetra-phenyl-porphyrin(H_2TPP)in benzene have been investigated by spin trapping-ESR technique. The ESR spectrum with 6 lines was detected in the presence of spin trap PBN, it means that spin adduct is [HTPPPBN]'. The ESR signal with 6 lines was quenched by O_2 and Nal, it can be concluded, therefore, that the photolysis process of H_2TPP was accomplished via triplet excited state.