4)酮酯缩合 酮的c-H比酯的c-H活泼。 0 0 0 CH3CCH3+CH3(CH2)4COOC2Hs 1)NaH →CH3(CH2)4CCH2CCH 2)H OCH3 O OCH3 O COOCH CH.CH-CHCCH CH3O CH30 0 CHCH2CCH3 OCH3 O CH3 O Na2CO3 Claisen缩合 CH30 H3C