Dibenzotetraaza Crown Ethers: A New Family of Crown Ethers Based on <i>o</i>-Phenylenediamine
作者:Sven H. Hausner、Cynthia A. F. Striley、Jeanette A. Krause-Bauer、Hans Zimmer
DOI:10.1021/jo050281z
日期:2005.7.1
benzimidizoles were used to produce DBTA crown ethers with modified substituents and ether bridges, as well as benzimidazolidine crown ethers. The synthetic approach presented here proved to be a convenient route to a new family of crown ethers with overall yields of up to 48% based on the benzimidazole. Yields for the ring-closing step were generally high, ranging from 51% to 94%, without the need for high-dilution
二苯并四氮杂(DBTA)冠醚具有两个邻-苯二胺部分。它们是二苯并冠醚相转移催化剂的同系物,由苯并咪唑与低聚(乙二醇)二氯化物和低聚(乙二醇)二甲苯磺酸酯的缩合反应制得。制备了环大小为18冠6至42冠14的化合物。另外,各种改变的苯甲二唑被用于生产具有修饰的取代基和醚桥的DBTA冠醚,以及苯并咪唑烷冠醚。事实证明,此处提出的合成方法是通向冠醚新家族的便捷途径,基于苯并咪唑,其总收率可达48%。闭环步骤的收率通常较高,在51%至94%的范围内,而无需高稀释条件。N-有机基)化合物。进行了苦味酸盐提取研究以确定相转移催化能力。碱金属离子的萃取效率低于二苯并18-冠-6的萃取效率。其他金属离子的效率较高,对Pb 2+具有一定的选择性。四(N-甲基)DBTA-18-crown-6的提取效率通常高于其N-H类似物,但选择性较低。