ANNULATED DERIVATIVES OF 2,2'-BIIMIDAZOLE, 2-(2'-IMIDAZOLYL)BENZIMIDAZOLE, AND 2,2'-BIBENZIMIDAZOLE

Preparation of bisannulated salts of 2,2'-biimidazole, 2-(2'-imidazoly l)benzimidazole, 2,2'-bibenzimidazole, and annulated salts of 1,1'-dim ethyl-2,2'-biimidazole, 1,1'-dimethyl-2-(2'-imidazolyl)benzimidazole, and 1,1'-dimethyl-2,2'-bibenzimidazole is accomplished by direct alkyl ation of the parent azaheterocycle with excess 1,n-dihaloalkane. Discu ssions of the product conformations use electronic absorption spectra and NMR. The redox potentials of these salts are measured in DMF and C H3CN, and become increasingly more negative and less reversible as the systems become less planar.