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A diketone or dione is a molecule containing two ketone groups. The simpliest diketone is diacetyl, also known as 2,3-butanedione. Diacetyl, acetylacetone, and hexane-2,5-dione are examples of 1,2-, 1,3-, and 1,4-diketones, respectively. Dimedone is an example of a cyclic diketone. ==1,2-Diketones== An important member is biacetyl, CH3C(O)C(O)CH3. These compounds are often generated by dehydrogenation of the diols:〔 :RCH(OH)CH(OH)R → RC(O)C(O)R + 2 H2 A distinctive feature of 1,2-diketones is the long C-C bond linking the carbonyl groups. This bond distance is about 1.54 Å, compared to 1.45 Å for the corresponding bond in 1,3-butadiene. The effect is attributed to repulsion between the partial positive charges of the carbonyl carbon atoms. 1,2-Diketones condense with many bifunctional nucleophiles, such as urea and thiourea to give heterocycles. Upon condensation with aromatic amines, they convert to the diketimine ligands. 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「Diketone」の詳細全文を読む スポンサード リンク
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