分子内电荷转移吩噁嗪衍生物的合成及溶致变色效应的研究  

Synthesis and solvatochromism of an intramolecular charge transfer phenoxazine derivative

作　　者：任泓扬[1] 吴义芳[2] 王炳喜[1] 

机构地区：[1]福州大学材料科学与工程学院,福州350116 [2]菏泽学院化学化工系,菏泽274015

出　　处：《化工新型材料》2015年第7期137-139,142,共4页New Chemical Materials

基　　金：福州大学科技发展基金资助项目(2010XQ02)

摘　　要：在钯催化剂条件下,2-(4-溴苯基)-1-苯基-1H-苯并咪唑(PPBI-Br)和吩噁嗪(PXZ)反应合成新型分子PPBIPXZ。采用核磁和质谱表征PPBI-PXZ的结构,紫外-可见光谱和荧光发射光谱探究其光物理性质,热重分析其热稳定性。量化计算结果表明:PPBI-PXZ分子的最高已占有轨道(HOMO)主要分布在供体PXZ部分,最低未占有轨道(LUMO)则分布在受体PPBI部分,供体和受体间的二面角达87.0°,电荷转移量0.891,S1态与T1态能级差计算值为0.28eV。在正己烷、甲苯、乙酸乙酯、二氯甲烷和乙腈5种极性递增的溶剂中,PPBI-PXZ在370nm附近出现吸收肩峰,其最大发射波长从419nm红移至577nm。这种显著的溶致变色现象展现了扭曲分子的分子内电荷转移(TICT)的特征。A new compound（PPBI-PXZ）was synthesized by the reaction of 2-（4-bromophenyl）-1-phenyl-1H-benzimidazole（PPBI-Br）with phenoxazine（PXZ）using apalladium catalyst.The compound was characterized by NMR and MS.Photophysical properties were investigated by UV-Vis and emission spectra.Thermal stability was determined by thermogravimetric analysis.The results of quantum chemistry calculation showed that the electron density of the HOMO state was localized on PXZ unit,while corresponding LUMO state was mainly distributed on PPBI unit.The dihedral angle between the PXZ and PPBI was 87.0°.The charge transfer amount（q）was 0.891.The calculated energy gap between the lowest singlet state（S1）and the lowest triplet state（T1）was 0.28 eV.In n-hexane,toluene,ethyl acetate,dichloromethane and acetonitrile,PPBI-PXZ solutions had an absorption shoulder around 370 nm and emitted light with maximum wavelengths from 419 nm to 577 nm.The obvious solvatochromism demonstrated the nature of intramolecular charge transfer of twisted molecule.

关 键 词：吩噁嗪 苯并咪唑 分子内扭曲电荷转移 溶致变色 量化计算 

分 类 号：O626[理学—有机化学]