5.合成下列化合物 C(CH3n (1) CH3C 解 MgBr HlR CH3COCH3 CH3 H2 SO4 C(CH3hz HCHO, CHCHO CH3COCH3 解 3HCHO+ CH, CHo Ca(ohh 〔HoCH2)3cCHo HCHO 2CH3 COCH (HOCH,,C a(OH)