A study about the scope of the method for the attainment of 4,5-dihydro-1H-imidazolium salts by dehydrogenation of N,N´-dibenzyland N-aryl-N´-benzylimidazolidines is presented. Employed dehydrogenating agents were N-bromoacetamide (NBA), N-bromosuccinimide (NBS), carbon tetrachloride and 1,3-dibromo-5,5-dimethylhydantoin (DBDMH). DBDMH was the choice reagent due to the purity of the attained products, lowest reaction times and highest yields.