Br2 B 构象改变最小原理 b.与卤化氢加成 Br H CH3-C=CH2+HBr CH3-C-CH3 CH3- C-CH2Br CH3 CH3 CH3 90% 10% Br + Br2 Br Br 1 2 4 3 5 6 Br - Br2 Br + Br - Br Br 1 2 3 4 5 6 构象改变最小原理 b. 与卤化氢加成 CH3 C=CH2 CH3 + HBr CH3 C CH3 Br CH3 + CH3 C CH2Br CH3 H 90% 10%