Wong Cheok-Lam, Poon Chun-Ting, Yam Vivian Wing-Wah
Institute of Molecular Functional Materials, (Areas of Excellence Scheme, University Grant Committee (Hong Kong)) and, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.
Chemistry. 2016 Aug 26;22(36):12931-40. doi: 10.1002/chem.201601585. Epub 2016 Aug 1.
A series of dithienylethene-containing boron(III) ketoiminates, as well as their corresponding β-ketoimine ligands, have been synthesized and characterized. The photophysical, electrochemical, and photochromic properties of the compounds have been studied. Photocyclization has been found to be suppressed upon introduction of a phenyl substituent on the nitrogen atom of the β-ketoiminate core, whereas photochromism could be observed by replacement of the phenyl substituent with a bulky mesityl group. It is believed that the steric effect of the mesityl unit restricts molecular rotation, resulting in such a prominent difference in the photochromic properties.
一系列含二噻吩乙烯的硼（III）酮亚胺及其相应的β-酮亚胺配体已被合成并表征。研究了这些化合物的光物理、电化学和光致变色性质。发现在β-酮亚胺核心的氮原子上引入苯基取代基会抑制光环化，而用庞大的均三甲苯基取代苯基取代基时可观察到光致变色现象。据信均三甲苯基单元的空间效应限制了分子旋转，从而导致光致变色性质上如此显著的差异。
