1,2-Disubstituted Hexahydro-1H-benzo[d]imidazoles: Synthesis, Characterization, and Stability

Starting from commercially available (hetero)aromatic nitriles and (1R,2R)-cyclohexane-1,2-diamine, nine NH-imidazolines (hexahydro-1H-benzo[d]imidazoles) were synthesized in good yields. The molecular structures of three imidazolines were confirmed by X-ray analysis. N-Benzylation afforded some of the desired N-benzylimidazolines, but was incompatible with imidazolines that possessed strong electron-accepting heteroaromatic groups at C2. In the latter cases, the products decomposed during column chromatography to form N,N′-disubstituted cyclohexane-1,2-diamines.