1、E2反应 ● Regiochemistry(区域选择性) Zaitsey's rule 从含氢较少的β-碳 上消去得到多取代基烯烃 CH3CHCH2CH3 OCH3 CH3=CHCH3 CH2=CHCH2 CH3 Br 80% 20% OH CH3CHCH2CH2CH3- CHa CH=CHCH, CHx CH2 =CHCH2CH2CH 67% 33% CH3 cH3ccH2cH3⊥OH CH3 CH3 CH3C=CHCH3 CH2=CCH2 CH3 c 70% 30%1、E2反应 Regiochemistry（区域选择性） Zaitsev’s Rule —— 从含氢较少的β-碳 上消去得到多取代基烯烃 C H3CHCH2C H3 B r - OCH3 CH3CH=CHCH 3 + CH2 =CHCH2CH3 C H3CHCH2C H2C H3 C l - OH CH3CH=CHCH 2CH3 + CH2 =CHCH2CH2CH3 80% 20% 67% 33% C H3CCH2C H3 C l C H3 - OH C H2 =CCH2C H3 C H3 C H3C=CHCH3 C H3 + 70% 30%