CH3 CH nO2 常用: Fe/hcl NH2 Fe/HCl Zn/HCl EtOH.△ NO 74 NH nO2 NH NH 12 Sncl s Naoh 浓HCl CHO CHO CHOCH3 NO2 NO2 Fe / HCl EtOH, CH3 NH2 NH2 74% NO2 CHO NH3 CHO NH2 CHO 浓 HCl SnCl2 NaOH 常用: Fe / HCl Zn / HCl