自卤仿产生二卤卡宾的单电子转移过程

研究了从卤仿和氢氧化钠生成二卤卡宾的反应,根据化学和物理研究证明,是一单电子转移(SET)的反应机理.在类卡宾、三卤碳阴离子和二卤卡宾间设有平衡存在,卤素交换是单电子转移过程中形成的三卤甲基和二卤甲基游离基所引起的,它优先于卡宾对C=C的加成而发生,反应的初始电子给予体是CX3主要电子接受体是过量存在的卤仿.

Single electron transfer mechanism in the generation of dihalocarbene from haloform

Based on chem. and phys. evidence, a single electron transfer (SET) mechanism for the generation of dihalocarbene from haloform and sodium hydroxide is suggested. No equilibrium exists between the carbenoid-trihalocarbanion and dihalocarbene, and the halogen-exchange brought about by trihalomethyl and dihalomethyl radicals formed via the single electron transfer process occurs prior to the addition of carbene to the carbon-carbon double bond. The primary electron donor in this reaction is CX3- (X = halo) and the main electron acceptor is the haloform present in excess.