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|Section2= |Section7= |Section8= }} Diethyl malonate, also known as DEM, is the diethyl ester of malonic acid. It occurs naturally in grapes and strawberries as a colourless liquid with an apple-like odour, and is used in perfumes. It is also used to synthesize other compounds such as barbiturates, artificial flavourings, vitamin B1, and vitamin B6. ==Structure and properties== Malonic acid is a rather simple dicarboxylic acid, with two the carboxyl groups close together. In forming diethyl malonate from malonic acid, the hydroxyl group (-OH) on both of the carboxyl groups is replaced by an ethoxy group (-OEt; -OCH2CH3). The methylene group (-CH2-) in the middle of the malonic part of the diethyl malonate molecule is neighboured by two carbonyl groups (-C(=O)-).〔(IR spectrum of Malonic acid )〕 The hydrogen atoms on the carbon adjacent to the carbonyl group in a molecule is significantly more acidic than hydrogen atoms on a carbon adjacent to alkyl groups (up to 30 orders of magnitude). (This is known as the α position with respect to the carbonyl.) The hydrogen atoms on a carbon adjacent to two carbonyl groups are even more acidic because on the – the carbonyl groups helps stabilize the carbanion resulting from the removal of a proton from the methylene group between them. : The extent of resonance stabilization of this compound's conjugate base is depicted by the three resonance forms below: : 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Diethyl malonate」の詳細全文を読む スポンサード リンク
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