Influence of Intermolecular Interactions on the Conformation of a 2-[Bis(2-Ethylphenyl)thiophosphorylhydroxymethyl]-l-Ethylbenzimidazole Molecule (L) upon Complex Formation with ZnCl_2: Crystal and Molecular Structures of Molecule L

摘要

The structures and conformations of a 2-[bis(2-ethylphenyl)thiophosphorylhydroxymethyl]-l-eth-ylbenzimidazole (L) molecule in the free form (L_(fr)) and in the [ZnCl_2L]L complex (I) are compared using the X-ray diffraction data. In complex I, one ligand molecule (L_c) is coordinated to the zinc atom in the bidentate chelating mode and the second molecule (L_(solv)) accomplishes the solvating function. An isomer with the cis orientation of the O(1) atom to the N(l) atom is observed in the crystal structure of L_(fr) like L_(solv) in complex I, with the formation of the five-membered corrugated H-heterocycle OC_2NH. L_(fr) and L_(solv) molecules differ in the arrangement of the aromatic rings of the 2R substituent of benzimidazole. Crystalline compound L forms dimeric associates in which three conjugate H-rings are closed by a bifurcate intermolecular hydrogen bond: two five-membered ONC_2H rings and one planar four-membered N_2H_2 ring ((N(1)…N(1A), 3.705 and H(1)…H(1A) 2.67 A). Unlike crystals of compound I with the pi-pi-stacking interaction between the planar-pap allel aromatic rings of benzimidazole of the L_(solv) and L_c molecules, the crystals of L have no similar interaction between the L_(fr) molecules.