“…In contrast, 1,1'-di (3,6,9-trioxadecyl)-4,4'-bipyridinium bis(tetrafluoroborate) and 1,1'-di (3,6,9-trioxadecyl)-4,4'-bipyridinium ditosylate are roomtemperature (RT) ionic liquids [5]. The 1,1'-diphenyl-4,4'-bipyridinium dialkylbenzenesulfonates that contain alkyl chains of length 10, 13, and 15 carbon atoms have T m values (205, 190 and 168 ‡C, respectively) above which each exhibits a SmA phase; the SmA phase for each then persists up to their decomposition temperatures (280-290 ‡C) [6]. Thus, it is evident that viologen compounds having suitably designed chemical architectures (dicationic salts), such as 1-alkyl-3-methylimidazolium, N-alkylpyridinium, and quaternary ammonium salts each of which is a monocationic salt [7][8][9], have great potential for the preparation of both RT ionic liquids (green solvents) and room temperature liquid crystalline (RTLC) ionic liquids (ordered reaction media).…”