Valera Jorge S, Sánchez-Naya Roberto, Ramírez Francisco J, Zafra José L, Gómez Rafael, Casado Juan, Sánchez Luis
Química Orgánica I, Facultad de Ciencias Químicas, UCM, Ciudad Universitaria, s/n, 28040, Madrid, Spain.
Departamento de Química Física, Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos s/n, 29071, Malaga, Spain.
Chemistry. 2017 Aug 16;23(46):11141-11146. doi: 10.1002/chem.201702391. Epub 2017 Jul 26.
The chiroptical features of supramolecular polymers formed from N-heterotriangulenes 1-3 have been investigated by circular dichroism (ECD) and vibrational circular dichroism (VCD) techniques. In solution, the CD spectra demonstrate that the helicity of the aggregates depends on only the stereogenic centres located at the peripheral chains. In the gel state, the chiroptical features are conditioned by the point chirality of the stereogenic centres and by the achiral solvent utilised. Sonication of the gels formed in CCl reveals both kinetic and thermodynamic phases. These findings reveal the presence of pathway complexity in the gel state triggered by sonication. The described solvent-induced helical stereomutation demonstrates that the gel state can be utilised as an outstanding benchmark for investigating uncommon chiroptical effects and to explore the rules of chirality transmission.
通过圆二色性（ECD）和振动圆二色性（VCD）技术研究了由N-杂三蝶烯1-3形成的超分子聚合物的手性光学特征。在溶液中，CD光谱表明聚集体的螺旋度仅取决于位于外围链上的手性中心。在凝胶态下，手性光学特征受手性中心的点手性和所使用的非手性溶剂的影响。在CCl中形成的凝胶的超声处理揭示了动力学和热力学阶段。这些发现揭示了超声处理引发的凝胶态中存在途径复杂性。所描述的溶剂诱导的螺旋立体突变表明，凝胶态可作为研究罕见手性光学效应和探索手性传递规则的出色基准。
