Relative reactivities of polyhalofluoroalkanes toward bromophilic or chlorophilic attacks have been evaluated for the first time by comparing the rates of halophilic attacks by a carbanion derived from the addition of...Relative reactivities of polyhalofluoroalkanes toward bromophilic or chlorophilic attacks have been evaluated for the first time by comparing the rates of halophilic attacks by a carbanion derived from the addition of a nucleophile to an olefin with the rate of β-elimination of the same carbanion intermediate. Relative reactivity orders of some polybromofluoroalkanes and polychlorofluoroalkanes are CF_2Br_2>CF_3CFBr_2 ~ CF_2BrCF_2Br>CF_3CBr_3, and CCl_4 > CF_3CCl_3 > CF_2ClCCl_3 > CFCl_3 > CFCl_2CFCl2 ~ CF_2ClCFCl_2. Early transition states for halophilic attacks are speculated.展开更多
文摘Relative reactivities of polyhalofluoroalkanes toward bromophilic or chlorophilic attacks have been evaluated for the first time by comparing the rates of halophilic attacks by a carbanion derived from the addition of a nucleophile to an olefin with the rate of β-elimination of the same carbanion intermediate. Relative reactivity orders of some polybromofluoroalkanes and polychlorofluoroalkanes are CF_2Br_2>CF_3CFBr_2 ~ CF_2BrCF_2Br>CF_3CBr_3, and CCl_4 > CF_3CCl_3 > CF_2ClCCl_3 > CFCl_3 > CFCl_2CFCl2 ~ CF_2ClCFCl_2. Early transition states for halophilic attacks are speculated.