Study of the mechanism of base induced dehydrobromination of trans-β-bromostyrene
作者:Mieczysław Mąkosza、Alexey A Chesnokov
DOI:10.1016/s0040-4020(03)00107-8
日期:2003.3
Observation that rates of dehydrobromination of trans-β-bromostyrene (1) and the Hofmann degradation of tetrabutyl ammonium cation depend on strength of base in different ways and that treatment of 1 with base results in fast abstraction of the β-proton imply the possibility that the dehydrobromination of 1 could proceed via α-elimination and Ph migration. In order to clarify this question, β-13C-labeled
观察到反式-β-溴苯乙烯(1)的脱氢溴化速率和四丁基铵阳离子的霍夫曼(Hofmann)降解以不同的方式取决于碱的强度,并且用碱处理1会导致β质子的快速提取暗示这种可能性1的脱氢溴化可通过α消除和Ph迁移进行。为了阐明该问题,β- 13 C标记1得到并进行脱溴化氢PTC其进入不进行pH的迁移。将所得到的结果与不可逆的E1cB机制是一致的。