Chloromethylethyl ether

Another approach, particularly valuable for the synthesis of imidazolium salts containing sterically hindered substituents, for example, multiple-substituted phenyl groups at the nitrogen atoms, consists of a two-step protocol (route D) [28]. Under mild conditions, lequiv of glyoxal is treated with 2equiv of arylamine in -propanol to form the corresponding diimine as an intermediate. Subsequent cyclization by condensation with chloromethylethyl ether leads to the desired diarylimidazolium salt in moderate yields (40 -47%) without the need of a purification step. 

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