Experimental Crystal data

R factor = 0.055; wR factor = 0.175; data-to-parameter ratio = 14.2. The benzimidazolone part of the title molecule, C17H25N3O3, is almost planar (r.m.s. deviation = 0.016 Å) and its mean plane is aligned at 7.9 (4) with respect to the mean plane of the nitro substituent. In the crystal, two molecules are disposed about a center of inversion, generating a N— H O hydrogen-bonded cyclic dimer with a R22(8) graph-set motif. Related literature For the crystal structure of 1-isopropenyl-1H-benzimidazol