Conducting redox polymers: investigations of polythiophene-Ru(bpy)3n+ hybrid materials
                                
                                    
                                        作者:S. Sherry Zhu、Richard P. Kingsborough、Timothy M. Swager                                    
                                    
                                        DOI:10.1039/a903193f
                                    
                                    
                                        日期:——
                                    
                                    A series of thiophene-appended Ru
   II
 (bpy)
   3
  derivatives, Ru(1)
   3
 , Ru(2)
   3
 , Ru(3)
   3
 , Ru(bpy)
   2
 (1), and Ru(bpy)
   2
 (2), and their resulting polymers have been synthesized and characterized. The bpy ligands 5,5′-bis(5-(2,2′-bithienyl))-2,2′-bipyridine, 1, 4,4′-bis(5-(2,2′-bithienyl))-2,2′-bipyridine, 2, and 4-(5-(2,2′-bithienyl))-2,2′-bipyridine, 3, all contain electrochemically polymerizable bithienyl moieties. The monomers Ru(2)
   3
 , Ru(3)
   3
 , Ru(bpy)
   2
 (1) and Ru(bpy)
   2
 (2) display spectroscopic features that are similar to the ligand-based and MLCT bands found for Ru(bpy)
   3
 . The cyclic voltammograms of all of these polymers display both metal-centered and thiophene-based electroactivity. High redox conductivity was found in poly(Ru(2)
   3
 ) and poly(Ru(3)
   3
 ) for both the thiophene-based oxidation and metal-based reduction processes. These results indicate that the polymers display charge localization for both the metal complexes as well as the tetrathienyl connecting units. The degree of interconnection (number of linkages) as well as the substitution pattern were found to control the conductivity of these polymers. The highest conductivity (3.3×10
   –3
  S cm
   –1
 ) was found for poly(Ru(2)
   3
 ), which is able to have up to 6 linkages with other ruthenium complexes as well as possessing a 4,4′-substitution pattern that allows effective orbital overlap of the conjugated polymer backbone with the ruthenium centers.
                                    一系列附有
噻吩的 Ru II (bpy) 3 衍
生物,包括 Ru(1) 3、Ru(2) 3、Ru(3) 3、Ru(bpy) 2 (1) 和 Ru(bpy) 2 (2),及其所得聚合物已被合成并表征。这些 bpy 
配体 5,5′-双(5-(2,2′-双
噻吩基))-2,2′-联
吡啶 (1)、1,4,4′-双(5-(2,2′-双
噻吩基))-2,2′-联
吡啶 (2) 和 4-(5-(2,2′-双
噻吩基))-2,2′-联
吡啶 (3) 均含有电
化学可聚合的双
噻吩基基团。单体 Ru(2) 3、Ru(3) 3、Ru(bpy) 2 (1) 和 Ru(bpy) 2 (2) 表现出与 Ru(bpy) 3 的
配体基和
金属-
配体转移 (MLCT) 带相似的光谱特征。这些聚合物的循环伏安图显示出
金属中心和基于
噻吩的电活性。在聚(Ru(2) 3) 和聚(Ru(3) 3) 中发现了较高的氧化还原导电性,适用于基于
噻吩的氧化过程和
金属基的还原过程。这些结果表明,这些聚合物在
金属络合物和四
噻吩连接单元上均表现出电荷局部化。连接的程度(连结数量)以及取代模式被发现会影响这些聚合物的导电性。聚(Ru(2) 3) 的导电性最高(3.3×10 –3 S cm –1),可与其他
钌络合物形成多达 6 个连接,同时具备 4,4′-取代模式,使共轭聚合物主链与
钌中心有效重叠。