Br NHCCF3 SNi2 F3CCN Br 75% Br 卤代环烷烃的S2反应 CI CH3 CH3 CH3 CH3 CH3 (A) (B) 6 反应活性与过渡态势能有关。 Br Br NHCCF3 N Cl O SNi2 75% ? F3CCN O Br N Cl 卤代环烷烃的SN2反应 CH3 CH3 Cl CH3 CH3 Cl (A) (B) H H H CH3 CH3 H H H CH3 CH3 Cl Cl Nu Nu 反应活性与过渡态势能有关。  -  -  -  -