酸催化(S1): CH3 CH3 CH3 ,c-c H2SO4 H3C-CH-C CH3 CH3OH 入cH,→山c-C-CH 0+ CH3 CH3 CH OH H,C-CH一C-CH H3C-CH- C-CH3 OH HOCH OH 酸催化（SN1)： H3C CH C HOCH3 CH3 CH3 OH H3C CH OH C CH3 CH3 CH3OH H2 SO4 CH C O H3C CH3 CH3 CH C O H3C CH3 CH3 H CH3OH H + H3C CH C CH3 CH3 OH OCH3