Synthesis and anion binding behaviour of diamide derivatives of pyrrole-2,5-diacetic acid
作者:Rongqing Li、Louise S. Evans、David S. Larsen、Philip A. Gale、Sally Brooker
DOI:10.1039/b412654h
日期:——
Four examples of bis-amidopyrrole derivatives of pyrrole-2,5-diacetic acid have been prepared. The reaction of diethyl pyrrole-2,5-diacetate with a large excess (24 equiv.) of N,N-dimethylethylenediamine gave N,N′-bis(2-dimethylaminoethyl)-1H-pyrrole-2,5-diacetamide (1). Three further examples, N,N′-bis[2-(2-pyridyl)ethyl]-1H-pyrrole-2,5-diacetamide (2), N,N′-bis(2-pyridylmethyl)-1H-pyrrole-2,5-diacetamide (3) and N,N′-dibenzyl-1H-pyrrole-2,5-diacetamide (4), were prepared in a one pot procedure by converting pyrrole-2,5-diacetic acid into the N-hydroxysuccinimide ester and then reacting this with four equivalents of the appropriate amine, 2-(2-aminoethyl)pyridine, 2-aminomethylpyridine or benzylamine, respectively. Compounds 1–4 are shown to be effective anion receptors in acetonitrile-d3 solution, with comparable binding affinities to those found for simple pyrrole-2,5-dicarboxamides, despite possessing a more flexible hydrogen bonding array.
现已制备出四种吡咯-2,5-二乙酸双脒吡咯衍生物。吡咯-2,5-二乙酸二乙酯与大量过量(24 等量)的 N,N-二甲基乙二胺反应,得到 N,N′-双(2-二甲基氨基乙基)-1H-吡咯-2,5-二乙酰胺(1)。另外三个例子,N,N′-双[2-(2-吡啶基)乙基]-1H-吡咯-2,5-二乙酰胺(2)、N,N′-双(2-吡啶基甲基)-1H-吡咯-2,5-二乙酰胺(3)和 N,N′-二苄基-1H-吡咯-2,5-二乙酰胺(4),是通过将吡咯-2、5-二乙酸转化为 N-羟基琥珀酰亚胺酯,然后分别与四种当量的适当胺、2-(2-氨乙基)吡啶、2-氨甲基吡啶或苄胺反应制备。研究表明,化合物 1-4 在乙腈-d3 溶液中是有效的阴离子受体,其结合亲和力与简单的吡咯-2,5-二羧酰胺相当,尽管其氢键阵列更为灵活。