摘要
研究了在无溶剂条件下,由铜盐催化的苄胺与查尔酮的C—N/C—C键活化串联反应,合成了一系列2,4,6-三芳基吡啶衍生物。重点考察了催化剂、反应温度和反应溶剂等因素对目标产物产率的影响,并通过核磁氢谱和碳谱对串联产物进行了结构鉴定。实验结果表明:在无溶剂情况下,三氟甲磺酸铜(Cu(OTf)_2)催化合成2,4,6-三芳基吡啶衍生物的产率高(60%~88%),该方法具有反应条件温和,原料易得和底物适用范围广等特点。
An efficient copper-catalyzed C—N/C—C bond cleavage of aromatic methylamines andα,β-unsaturated ketones was developed to construct 2,4,6-triarylpyridine derivatives under neat conditions.The effects of catalyst,reaction temperature and solvent were studied.The product structures were characterized by 1 H NMR and 13 C NMR.This simple fragment assembly strategy uses mild conditions and affords a broad range of 2,4,6-triarylpyridine derivatives in up to 60%-88% yield from simple and readily available starting materials.This method has the advantages of operational simplicity,simple and readily available starting materials and wide substrate scope.
引文
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