羟脯氨酸衍生物催化syn-Aldol反应的研究
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摘要
本文以羟脯氨酸为原料,设计合成了一系列磺酰胺和硫脲类化合物,并将其作为双功能催化剂用于催化正己醛与对硝基苯甲醛的不对称Aldol反应的研究,筛选出效果较好的催化剂。系统考察了溶剂,添加剂,温度等因素对反应活性和选择性的影响。结果表明,通过催化剂的筛选和条件优化,能顺利得到醛与醛交叉Aldol反应的产物,产率适中,并且产物以syn构型为主。这类syn-Aldol催化反应的报道较少。
In this dissertation, a series of sulfonamides and thioureas were designed and synthesized from hydroxyproline, these compounds were screened as bifunctional organocatalysts in catalyzing the asymmetric Aldol reaction of hexanal with 4-nitrobenzaldehyde and the catalyst with good catalytic efficiency was identified. The influence of solvent, additive and temperature etc on the reactivity and enantioselectivity were optimized systematically. The research results demonstrated that the direct cross-Aldol reaction between two different aldehydes under the optimization reactive conditions could proceed smoothly to obtain the major.syn-configuration product with moderate yield. Resulting in this kind of.syn-selective aldol product was seldom being reported.
In this dissertation, a series of sulfonamides and thioureas were designed and synthesized from hydroxyproline, these compounds were screened as bifunctional organocatalysts in catalyzing the asymmetric Aldol reaction of hexanal with 4-nitrobenzaldehyde and the catalyst with good catalytic efficiency was identified. The influence of solvent, additive and temperature etc on the reactivity and enantioselectivity were optimized systematically. The research results demonstrated that the direct cross-Aldol reaction between two different aldehydes under the optimization reactive conditions could proceed smoothly to obtain the major.syn-configuration product with moderate yield. Resulting in this kind of.syn-selective aldol product was seldom being reported.
引文
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