有机合成中的保护基 如何制备5-甲基-5-羟基己酮-2? C>2CH3Mgl oEt 需要保护 OH OMg OMg OEt CH3MgI O OH t br. EtoNa OH CO2Et CO2Et (1)CH3 Mgl OEt HO OH OEt (1)H OH如何制备5-甲基-5-羟基己酮-2 ? O O O OEt 2CH3MgI OH + 需要保护 O O OEt CH3MgI OMgI O + OMgI OMgI H3O OH OH HO OH HCl O O O OEt OEt O O Br OEt O + EtONa (1) O CO2Et CO2Et H3O O O OH O O OEt CH3MgI (1)H3O O OH 一、有机合成中的保护基