【摘要】 无溶剂下,无水NaHSO4催化环己酮(或环戊酮)和芳香醛的Cross-Aldol缩合,合成了14个相应的α,α’-双亚苄基环酮。探讨了醛酮物质的量比、反应温度和催化剂的量对反应的影响,利用薄板层析(TLC)确定了反应时间。该反应的优化条件为:n(芳醛,4.1 mmol)∶n(环酮)=4.1∶2.0,反应温度60~65℃,催化剂0.5mmol,反应时间2.0~4.0 h,产率可达81%~93%。产物经熔点、红外光谱和核磁共振波谱分析确证。结果表明,该方法具有反应条件温和、操作和后处理简单、产率高、污染少等特点。更多还原

【Abstract】 The cross-aldol condensations of aromatic aldehydes with cyclohexanone or cyclopentanone catalyzed by anhydrous NaHSO4under solvent-free conditions have afforded 14 α,α’-bis( substituted-benzylidene) cycloalkanones.The reaction conditions,namely,molar ratios of aromatic aldehydes to cycloalkanones,reaction temperatures and the catalyst loading were optimized. Reaction times were determined by thin layer chromatography( TLC). The optimum reaction conditions were as follows: the molar ratio of aromatic aldehydes to cycloalkanones was 4. 1 ∶ 2. 0,reaction temperature was 60 ~ 65 ℃,mass ratio of catalyst was 0. 5 mmol and reaction time was 2. 0 ~ 4. 0 h. High yields,81%~ 93%,of the products were achieved. The products were characterized by melting points,IR and1H NMR spectroscopy. The experimental results showed that the method possesses the advantages of mild reaction condition,simple operation and easy after-treatment,good yields and less pollution.更多还原