Patent ID: 6713631
Filing Date: 2004-03-30
Classification: C07D

Abstract:
A preparation method of 2,2â€²-bi-1H-imidazole which comprises reacting glyoxal with excess amount of an ammonium salt selected from the group consisting of ammonium acetate, ammonium benzoate, ammonium bromide, ammonium carbonate, ammonium chloride, ammonium chromate, ammonium dichromate, ammonium formate, ammonium nitrate, ammonium oxalate, ammonium sulfamate, ammonium sulfate, ammonium sulfite, ammonium tartarate, ammonium tetrafluoroborate, ammonium thiocynanate and ammonium thiosulfate, wherein the reaction scheme is: and wherein NH4+Aâˆ’ represents an ammonium salt.