Serial double nucleophilic addition of amines to the imidazole nucleus

2-(1-Chloro-2,2-dimethylpropyl)-1-methyl-1H-imidazole hydrochloride (2a.HCl ) was treated with an excess of N,N-dimethylamine at room temperature to gi ve an abnormal addition product, 4,5-bis(N,N-dimethylamino)-1-methyl-2-(2,2 -dimethylpropyl)-2-imidazoline (4a), in 74.2% yield together with a normal S(N)2 product, 2-(1-N,N-dimethylamino-2,2-dimethylpropyl)-1-methyl-1H-imida zole (3a), in 15.0% yield. The former might be evolved from a serial double nucleophilic addition of the secondary amine molecules to the imidazole nu cleus, which has been generally considered as an electron-excessive and sta ble aromatic ring. (C) 2000 Elsevier Science Ltd. All rights reserved.