作者:Peng Hui Yang、Qun Zheng Zhang、Hong Jiang Yu
DOI:10.1007/s11164-011-0471-z
日期:2012.9
To obtain 2-benzimidazolyl acrylate 2, a new efficient synthesis of 2-benzimidazoleacetate, involving esterification of 2-benzimidazole acetic acid at low temperature as the crucial step, was developed. The generality and efficiency of the process was illustrated by the high-yield synthesis of methyl, ethyl, i-propyl, and n-butyl 2-benzimidazoleacetate. The Knoevenagel reaction of 2-benzimidazoleacetate with aromatic aldehydes was studied. It was found that only in the presence of a catalytic amount of morpholine could the Knoevenagel reaction proceed to give the expected 3-aryl-2-benzimidazolyl acrylate. A mechanism for the morpholine-catalyzed reaction is suggested.
为获得2-苯并咪唑基丙烯酸酯2,开发了一种高效的新合成方法,涉及在低温下对2-苯并咪唑乙酸进行酯化,这是关键步骤。通过高产率合成甲基、乙基、异丙基和正丁基2-苯并咪唑乙酸,证明了该过程的普适性和效率。研究了2-苯并咪唑乙酸与芳烃醛的Knoevenagel反应。结果发现,只有在催化量的吗啉存在下,Knoevenagel反应才能进行,生成预期的3-芳基-2-苯并咪唑基丙烯酸酯。提出了一种吗啉催化反应的机制。