方酸内鎓盐骨架桥接双冠醚的合成

SYNTHESIS OF BIS-CROWN ETHERS BRIDGED BY SGNAROINE SKELETON

冠醚的离子识别功能早已为人们熟知,并在相转移催化,手性氨基酸的合成与折分,稀有金属及放射性元素的分离与富集,酶摸拟等研究领域应用十分广泛.拥有两个离子识别部位的双冠醚能形成可能满足不同需求的双核或夹心型金属配合物,因而越来越引起人们的兴趣.目前,已有数量众多的以脂肪链或芳环等为栈桥的双冠醚相继出现。发展双冠醚的新品种,寻找新的有效合成方法无疑将对双冠醚的研究起到促进作用。作为一个双功能基化合物,方酸能桥接两个结构片段形成具有多种特性的方酸内鎓盐。因此。

In this communication two bis—crow ethers 3 and 5 bridged by 2, 4—dioxocyclobutene component have been synthesized by two different routes. The aromatic amino squarylium bis—crow ether 3 is obtained coveniently by reacting squaric acid with crown 2—, whereas the ali—phatic amino squarylium bis—crown ether 5 is synthesized in good yield by the transamidation of bis (2—nitroanilino)squaraine with crown 4.