脂族酰基过氧化物分解动力学的研究——Ⅹ.过氧化酰热分解反应的自旋捕获 ESR 研究

Studies on the Kinetics of Decomposition of Diacyl Peroxides——Ⅹ.An ESR Study of the Trapping Experiment of Thermal Decomposition Products

脂族酰基过氧化物在非极性溶剂中的热分解反应主要是自由基过程.但由于反应中生成的酰氧基自由基RCOO·和其脱羧生成的烷基自由基R·都是短寿命自由基,不能直接用ESR检测.

C-Phenyl-N-t-butylnitrone(PBN),nitrosobenzene(NB)and t-nitrosobutane(TNB)have been used as spin-trapping agents for the trapping and detection ofshort-lived alkyl radicals formed during the decomposition of several diacyl peroxides(CH3)2 CH(CE2)3(6),(CH3)2CHCH2(7),(CH3)3 CCH2(8)and(CH3)3CCH2CH(CH3)CH2(9)]in benzene or carbon tetrachloride.The ESR spectra of the nitroxide radicals producedby the addition of alkyl radicals to spin-trapping agents have been recorded.It isobserved that the hydrogens ofα-CH2 in 2,4,4-trimethyipentyl radical are diastereoto-pic and nonequivalent and,on account of this,the ESR spectrum produced from theadduct with this radical is different from that with the other radicals.