与烯烃的加成〔与碳正离子的反应) CH CH R一OH+H2c R=一c-cH3 CH3 CH 叔丁基醚 机理: CH 3 H2c H R ≥cH2 H3C-CO H3C CH CH3 CH3 R-Qc—cH3 R-O-C-CH3 CH 3 CH3◼ 与烯烃的加成（与碳正离子的反应） 机理： H2C CH3 CH3 H + R OH + R O C CH3 CH3 CH3 叔丁基醚 CH2 H3C H3C H + HO R H － + C CH3 H3C CH3 O H R C CH3 CH3 CH3 R O C CH3 CH3 CH3