Thiophen-2-yl and bithienyl substituted pyrazine-2,3-dicarbonitriles as precursors for tetrasubstituted zinc azaphthalocyanines
作者:Eva H. Mørkved、Trygve Andreassen、Roland Fröhlich、Frode Mo、Susana V. Gonzalez
DOI:10.1016/j.poly.2013.02.017
日期:2013.4
coplanarity between the two ring systems, and red-shifted UV–Vis Q-bands are observed. This lowering in energy is favourable for various applications. Pyrazine-2,3-dicarbonitriles substituted in the 5-position with alkyl-thiophen-2-yl groups or bithienyl groups, were synthesized as precursors for the parent tetrasubstituted ZnAzaPcs, expected to show further red-shifted Q-bands. The reagent Zn(quinoline)2Cl2
外围的噻吩-2-基取代基扩展了锌(II)氮杂酞菁(ZnAzaPc)的大环共轭,这是由于两个环系统之间存在共面性,并且观察到了红移的UV-Vis Q谱带。能量的降低对于各种应用是有利的。合成了在5位上被烷基噻吩-2-基或双噻吩基取代的吡嗪2,3,3-二腈,作为母体四取代ZnAzaPcs的前体,预计还会显示出红移的Q带。Zn(喹啉)2 Cl 2试剂用于一步环四聚。没有被二噻吩基取代的前体产生干净的反应,并且主要得到聚合物材料。获得了分别分别被5-乙基-噻吩-2-基和3,4-二甲基-噻吩-2-基四取代的两个ZnAzaPcs,收率为40-50%。对于两种四聚体的蓝绿色DMF溶液,在660 nm处有UV-Vis Q谱带,摩尔消光系数为111000和89000 M-1 cm-1。2D NMR方法应用于DMF-d7溶液的分析。两种化合物的1H NMR信号的部分重叠,表明存在聚集现象。另外,光谱中尖峰的广