Kubota Yasuhiro, Kasatani Kouhei, Takai Hiroki, Funabiki Kazumasa, Matsui Masaki
Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.
Dalton Trans. 2015 Feb 21;44(7):3326-41. doi: 10.1039/c4dt03318c.
The synthesis and the solution/solid-state fluorescence properties of pyrimidine-based monoboron complexes differing in terms of the substituents [either two fluorine atoms (BF2 complex) or two phenyl groups (BPh2 complex)] on the boron atom are reported herein. Unrestricted C-Ar intramolecular rotation in the non-, trifluoromethyl-, and cyano-substituted derivatives resulted in negligible fluorescence in solution. On the other hand, methoxy- and dimethylamino-substituted analogues caused the restriction of the C-Ar intramolecular rotation and consequently resulted in relatively strong fluorescence in solution. The non-, trifluoromethyl-, and cyano-substituted derivatives showed a pronounced aggregation-induced emission enhancement effect. Dimethylamino-substituted derivatives exhibited solvatochromism in the fluorescence spectra. Substitution with BPh2 effectively enhanced the fluorescence quantum yield compared to the corresponding BF2 complexes in the solid-state.
本文报道了硼原子上取代基不同（两个氟原子（BF2配合物）或两个苯基（BPh2配合物））的嘧啶基单硼配合物的合成及其溶液/固态荧光性质。在未取代、三氟甲基取代和氰基取代的衍生物中，不受限制的C-Ar分子内旋转导致溶液中的荧光可忽略不计。另一方面，甲氧基和二甲基氨基取代的类似物导致C-Ar分子内旋转受到限制，从而在溶液中产生相对较强的荧光。未取代、三氟甲基取代和氰基取代的衍生物表现出明显的聚集诱导发光增强效应。二甲基氨基取代的衍生物在荧光光谱中表现出溶剂化显色现象。与相应的BF2配合物相比，用BPh2取代有效地提高了固态下的荧光量子产率。
