2-[(Cyclo­penta-1,3-dien-2-yl)diphenyl­meth­yl]-1-methyl-1H-imidazole

The title compound, C(22)H(20)N(2), (Ib), forms along with 2-[(cyclo-penta-1,3-dien-1-yl)diphenyl-meth-yl]-1-methyl-1H-imid-azole, (Ia), which differs with respect to the position of the double-bonds in the C(5)H(5) ring, in an approximately 3:7 ratio (Ia:Ib; NMR spectroscopy data). However, in a single crystal, only compound (Ib) is present. H atoms of the CH(2) group (C(5)H(5) ring) were found from the difference Fourier synthesis and refined isotropically using the riding model. Hypothesis on possible presence of the (Ia) isomer in crystal lattice (model with a C(5)H(5) ring disordered between two positions) was especially checked and rejected due to its inconsistency. In the crystal structure, no significant hydrogen-bonding inter-actions between the CH(2) groups of the C(5)H(5) rings and nonsubstituted N-atoms of the imidazole rings were observed. Despite the fact that the chemically achiral compound (I) crystallizes in a chiral space group P2(1)2(1)2(1), neither the absolute structure determination nor assignment of the inversion twinning was possible in the absence of a heavy atom.