摘要
以乙酰乙酸苄酯(4)为原料,经Knorr缩合制备了2,4-二甲基-3-丙酸甲酯基-5-羧酸苄酯基-1-氢吡咯(2)和2,4-二甲基-3-羧酸甲酯基-5-羧酸苄酯基-1-氢吡咯(3)。乙醚介质中,溴水氧化条件下,吡咯(2)发生自身缩合生成二吡咯甲烷(7),吡咯(3)无反应发生。在Pb(OAC)4氧化条件下,当其浓度为吡咯(3)浓度的2倍时,在80℃,吡咯(3)完全转化,所得产物经HCl甲醇溶液回流,以82%的产率制备了新型2-甲氧基甲基-3-羧酸甲酯基-4-甲基-5-羧酸苄酯基-1-氢吡咯(1)。吡咯(1)、(2)、(3)及二吡咯(7)的结构用核磁、元素分析、质谱和红外测试技术进行了表征。吡咯(1)的构建对进一步研究吡咯构效关系具有一定参考价值。
2,4-Dimethyl-3-(3-methoxy-3-oxopropyl)-5-benzylcarboxylate-1H-pyrrole(2) and 2,4-dimethyl-3-methoxymethyl-5-benzylcarboxylate-1H-pyrrole(3) were synthesized from benzyl ethylacetate(4) via the Knorr condensation reaction.In the ether solution of bromine,pyrrole(2) was converted to the corresponding dipyrromethane(7) through self-condensation,while no reaction happened to pyrrole(3).Under the 2 mol/L Pb(OAC)4 oxidative condition,when it was twice the concentration of pyrrole(3),at 80 ℃,pyrrole(3) was completely consumed.After the subsequent refluxing in the methanol solution of hydrochloride acid,a novel 2-methoxymethyl-3-methylcarboxylate-4-methyl-5-benzylcarboxylate-1H-pyrrole(1) was synthesized in a yield of 82%.Pyrrole(1),pyrrole(2),pyrrole(3) and dipyrrolemethane(7) were characterized through NMR,elemental analysis,MS and IR.The construction of pyrrole(1) will be helpful for the further study of the structure-functionality relationship of pyrrole derivatives.
出处
《应用化学》
CAS
CSCD
北大核心
2010年第1期48-52,共5页
Chinese Journal of Applied Chemistry
基金
国家自然科学基金(20802002)
安徽省教育厅基金(KJ2009A130)资助项目