Orthoamide und Iminiumsalze, LXXXVIII. Synthese N,N,N′,N′,N″,N″-persubstituierter Guanidiniumsalze aus N,N′-persubstituierten Harnstoff/Säurechlorid-Addukten**
AbstractN,N,N′,N′,N″,N″-Hexamethylguanidinium chloride9cwas prepared by treating the reaction mixture formed fromN,N,N′,N′-tetramethylurea (1a) and phthaloyl chloride (16) with dimethyltrimethylsilylamine15.N,N,N′,N′-Tetramethyl-chloroformamidinium chloride (2a) is an intermediate in this synthesis. The chloroformamidinium chloride2acan also be prepared by treating the urea1awith thionyl chloride or phosphorus pentachloride, respectively. The guanidinium salt9ccan be obtained from the crude2athus prepared and the silylamine15. From urea/phosphoryl chloride adducts and primary aromatic amines have been prepared guanidines38, which are converted toN,N′-diaryl-N,N′,N″,N″-tetramethyl-guanidinium iodides39on treatment with methyl iodide. TheN,N′,N″-trimethyl-N,N′,N″-triphenylguanidinium salt44awas prepared from the chloroformamidinium salt43andN-methylaniline. The guanidinium salt9cis the reaction product when the urea1a/POCl3adduct is treated with the silylamine15.