Control of Self-Assembly of a 3-Hexen-1,5-diyne Derivative: Toward Soft Materials with an Aggregation-Induced Enhancement in Emission

The supramolecular architectures of a fluorophore are controlled through the design of a conjugated polycatenar molecule, the self-assembly of which can be addressed toward a columnar liquid-crystalline phase and organogels. Thus, depending on the environmental conditions for self-assembly, compound CA9 organizes into an unprecedented hexagonal columnar mesophase in the condensed state, in which half a molecule constitutes the slice of the column, or into a rectangular mesomorphic-like organization in the presence of apolar solvents such as cyclohexane and dodecane, at a concentration in which fibers form and gelling conditions are fulfilled. In this Colr-type arrangement, the organization within the columns depends on the solvent. All of the materials prepared show luminescence, and moreover, a remarkable 3-fold increase in fluorescence intensity was observed in going from the solution to the gel state.

本研究通过设计共轭多链分子，实现对荧光团超分子组装结构的精准调控，该分子的自组装可定向形成柱状液晶相与有机凝胶。据此，根据自组装的环境条件差异，化合物CA9可在凝聚态下自组装为前所未有的六方柱状介晶相（此时半个分子构成柱切片）；或在环己烷、十二烷等非极性溶剂中，当处于满足纤维形成与凝胶化条件的浓度时，形成类矩形介观有序结构。在该Colr型有序结构中，柱内的组装模式随溶剂种类变化而改变。所有制备得到的材料均具备发光特性，且从溶液态转变为凝胶态时，荧光强度显著提升至原有的3倍。