Synthesis, spectroscopic studies and structural characterisation of some new 2-(phosphonioaryl)imidazolide betaines
作者:David W. Allen、Jacqueline Hawkrigg、Harry Adams、Brian F. Taylor、David E. Hibbs、Michael B. Hursthouse
DOI:10.1039/a704358i
日期:——
The synthesis is described of three series of 2-(phosphonioaryl)(benz)imidazolide betaines, viz (i) the 2-(2- or 3- or 4-tributylphosphoniophenyl)benzimidazolides, (ii) the 2-(2- and 4-triorganophosphoniophenyl)-1H-phenanthro[9,10-d]imidazolides, and (iii) the 2-(2- and 4-triorganophosphoniophenyl)-4,5-diphenylimidazolides. A detailed 1H, 13C and 31P NMR study of the 2-(tributylphosphoniophenyl)benzimidazolides reveals significant differences in the spectroscopic parameters of the betaines compared with those of the phosphonium salts from which they are derived. Full X-ray structural studies are reported for 2-(4-triphenylphosphoniophenyl)-1H-phenanthro[9,10-d]imidazol-1-ide and 2-(4-triphenylphosphoniophenyl)-4,5-diphenylimidazol-1-ide, and comparisons made with related pyridiniumimidazolide systems. The phosphonioimidazolide betaines exhibit negative solvatochromism.
描述了三个系列的2-(膦酰基芳基)(苯并)咪唑化物甜菜碱的合成,即(i) 2-(2-或3-或4-三丁基膦酰基苯基)苯并咪唑化物,(ii) 2-(2-和4) -三有机膦酰基苯基)-1H-菲并[9,10-d]咪唑化物,和(iii)2-(2-和4-三有机膦酰基苯基)-4,5-二苯基咪唑化物。 2-(三丁基膦酰基苯基)苯并咪唑化物的详细 1H、13C 和 31P NMR 研究表明,与衍生甜菜碱的鏻盐相比,甜菜碱的光谱参数存在显着差异。报告了 2-(4-三苯基膦酰基苯基)-1H-菲[9,10-d]咪唑-1-ide 和 2-(4-三苯基膦酰基苯基)-4,5-二苯基咪唑-1-ide 的完整 X 射线结构研究,并与相关吡啶鎓咪唑化物系统进行比较。膦酰咪唑甜菜碱表现出负溶剂化变色现象。