Synthese und Reaktionen von 1,2,4,5-Tetramethylimidazol; die Kristallstruktur von Pentamethylimidazolium-iodid / Synthesis and Reactions of 1,2,4,5-Tetramethylimidazole; the Crystal Structure of Pentamethylimidazolium Iodide

1,2,4,5-Tetramethylimidazole (3) is obtained by metalation of 2,4,5-trimethylimidazole (2) with sodium in liquid ammonia and subsequent addition of methyl iodide. 3 reacts with Lewis acids to form the compounds Me4C3N2 · BH3 (8) and Me4C3N2 · E+ (4, 5, 7, 10; E = Me, H, SiMe3, C(O)Me). The X-ray structure reveals the ionic nature of pentamethylimidazolium iodide (4) in the solid state.