三蝶烯衍生的双氮杂双氧杂杯芳烃的合成与结构

Synthesis and Structures of Triptycene-derived Diazadioxacalixarenes

2,7-二氨基三蝶烯、2,7-二羟基三蝶烯与杂环化合物如三聚氰氯、1,5-二氟-2,4-二硝基苯和2,6-二氯-3,5-二氰基吡啶等通过两步芳香亲核取代反应得到系列双氮杂双氧杂杯芳烃大环分子.通过核磁谱以及X射线单晶衍射研究其在溶液中及固态下的结构以及组装行为.

A series of triptycene-derived diazadioxacalixarenes were synthesized by two-step SNAr reactions from 2,7-diaminotriptycene,2,7-dihydroxytriptycene with heterocyclic compounds such as cyanuric chloride,1,5-difluoro2,4-dinitrobenzene and 2,6-dichloropyridine-3,5-dicarbonitrile,respectively.X-Ray crystallographic analysis of the trimer obtained by reaction of 2,7-diaminotriptycene with 2,6-dichloropyridine-3,5-dicarbonitrile showed that the two pyridine rings are in the same side of the triptycene unit and the two residual chloride atoms point to the same direction,which greatly favors the subsequent cyclization reactions with 2,7-dihydroxytriptycene.Due to the 3D characteristic of triptycene unit,the synthetic macrocyclic molecules are pairs of diastereomers.Their structures and self-assembled properties were studied by NMR spectra and X-ray crystallographic analysis.The results showed that the diazadioxacalixarenes have some different properties from those of tetraazacalixarenes and tetraoxacalixarenes.The triptycene-derived tetra-NH-bridged azacalixarenes obtained from the reaction of 2,7-diaminotriptycene with 2,6-dichloropyridine-3,5-dicarbonitrile can self-assemble into a large square-shaped organic nanotube with aromatic single-walled surfaces by four infinite one-dimensional H-bond chains,and the nanotubes could further assemble into a 3D honeycombed architecture.However,the diazadioxacalixarene analog could not self-assemble into such architecture due to the structural and conformational changes made by the displacement of two bridging nitrogen atoms with oxygen atoms,which led to the destroy of the H-bond chains formed from the bridging NH groups with the cyano groups.Our results also showed that the trimer of 2,7-diaminotriptycene and 2,6-dichloropyridine3,5-dicarbonitrile could self-assemble into a nanotube architecture with a hole diameter of 8.16 ×8.95 through C—H… Cl H-bond（dH…Cl=2.87,θC—H…Cl=149.31°）,π…π（dπ…π=3.67） stacking and C—H…π（dC—H…π=2.86） interactions.