H LO 21 2. Zn/H2O CHO CHO OH 4)CHCH=CH OCH CH= CHCH3 CH3 H HBI 答 CH,=CHCH,OH CHzCOOH 答:CH2= CHCHO CH-CH2CF CH3ONa CHCHOH HOH Naoh CH3 CH= CHCH,CI OH 答 - oNa OCH, CH=CHCH3 比C以 HIO A O 27. HO OH 答:HC CH3CHCHCHCH 3+ HBr OCH CH3 CH2CHCH2CH HbR OH CH38 21． H + OH 1. O3 2. Zn/H2O 答： CHO CHO 22． OCH2CH CHCH3 答： CH3 CHCH CH2 OH 23． OH + HBr 答： Br 24． CH2 CHCH2OH CrO3 CH3COOH 答： CH2 CHCHO 25． CH3ONa CH3OH CH CH2 O 答： CHCH2OH OCH3 26． OH N CHCH2Cl aOH CH3CH 答： ONa OCH2CH CHCH3 27． CH3 H HIO4 3C HO OH 答： H3C CH3 OO 28． CH + HBr 3CH2CHCH2CH3 OCH3 + 答： + OH CH3CH2CHCH2CH3 CH3Br 29． H + CH HO OH 答： O