四氨基柱[5]芳烃二聚体的合成、结构及性质研究  

Tetraaminopillar[5]arene Dimers:Synthesis,Structure and Properties

作　　者：吴明港 杨勇[2] 薛敏 Wu Minggang;Yang Yong;Xue Min(Department of Physics,Zhejiang Sci-Tech University,Hangzhou 310018;Department of Chemistry,Zhejiang Sci-Tech University,Hangzhou 310018)

机构地区：[1]浙江理工大学物理系,杭州310018 [2]浙江理工大学化学系,杭州310018

出　　处：《化学学报》2022年第8期1057-1060,共4页Acta Chimica Sinica

基　　金：国家自然科学基金(Nos.21772178,21971223)资助。

摘　　要：构象固定的刚性多环主体分子为构筑高级复杂的机械互锁结构提供了重要平台.为挑战合成刚性多环主体并进一步构筑多层次机械互锁结构,氧杂杯[4]芳烃桥连的柱[5]芳烃二聚体经过Raney Ni催化氢化还原硝基、与叔丁氧羰基(Boc)-β-丙氨酸缩合和脱去N-Boc保护基三步反应,生成了四氨基柱[5]芳烃二聚体.X射线单晶衍射实验表明三环目标主体分子具有双桶望远镜形状,并且构象刚性,随取代基不同仅有微小变化.此外,该四氨基二聚体可作为主体与己二腈形成高稳定性的1∶2络合物.该研究为制备复杂超分子体系提供了新的机会.Multi-macrocyclic hosts with fixed conformations provide important platforms for the construction of complicated mechanically inter-locked structures.In order to synthesize rigid multi-macrocycles,a type of oxacalix[4]arene-bridged pillar[5]arene dimers were further derivatized.Firstly,the four NO2 groups in pillar[5]arene dimer 1 were reduced under catalytic hydrogenation conditions using Raney Ni as a catalyst to give tetraamino compound 2.Unfortunately,the aromatic amino groups in compound 2 were unstable in the air and hard for next investigation of molecular recognition.Therefore,further derivatization was used to introduce more stable aliphatic amino groups.After multiple optimization attempts,the“1+4”intermediate product 3 was obtained in a high yield of 72% from reaction of compound 2 and ten equivalents of t-butoxycarbonyl(Boc)-β-alanine 5 in the presence of dicyclohexylcarbodiimide(DCC)at room temperature.The N-Boc protection groups were further removed in the presence of trifluoroacetic acid in CHClto afford target compound 4 with four aliphatic amino groups.The structure of 4 was thoroughly confirmed by nuclear magnetic resonance(NMR),high resolution mass spectrometry(HRMS)and X-ray single crystal analysis.X-ray single crystal analysis indicated that the tricyclic host had a shape of binoculars and the conformation was rigid,which could be slightly tuned by different substituents.With a pillar-calix-pillar structure,the host-guest properties of compound 4 were investigated subsequently.Because of its small cavity,oxacalix[4]arene unit played just a role of framework to make two pillar cavities parallel and appropriate for association with guest molecules.The dimers 4 could associate with 1,4-dicyanobutane and form the complex of 2G?4 with strong binding ability.The binding constants(K_(1)=3.9×10^(4) L·mol^(-1),K_(2)=2.4×10^(4) L·mol^(-1),K_(a)=9.4×10^(8) L^(2)·mol^(-2))were determined by ultraviolet and visible(UV-Vis)spectroscopy.The complexation between pillar[5]arene dimer 1 with NOgroup

关 键 词：大环 芳烃二聚体 芳烃 构象固定 主客体化学 

分 类 号：O625.1[理学—有机化学]