4(5)-Monosubstituted imidazoles (9) have been prepared via base-induced cycloaddition of tosylmethyl isocyanide (TosMIC) to N-(dimethylsulfamoyl)aldimines (2) or N-tosylaldimines (3). In the first case, N-(dimethylsulfamoyl)imidazoles 8 are the initial reaction products, from which the dimethylsulfamoyl group is readily removed with aqueous HBr. In the second case, the tosyl group of 1-tosylimidazoles
4(5)-单取代的
咪唑(9)是通过将
甲苯磺酰基甲基异
氰化物(TosMIC)与N-(二甲基
氨磺酰基)醛
亚胺(2)或N-
甲苯磺酰基
亚胺(3)进行碱诱导的环加成而制备的。在第一种情况下,N-(二甲基
氨磺酰基)
咪唑8是初始反应产物,可以用HBr
水溶液很容易地从中除去二甲基
氨磺酰基。在第二种情况下,在一个操作中,1-
甲苯基
咪唑10的
甲苯磺酰基自发地丢失,得到4(5)-单取代的
咪唑9。