Syntheses and Crystal Structures of Two Copper Complexes Based on Thienyl and Pyridyl Substituted Triaryltriazoles

Two new copper(II) complexes, trans-[Cu(L-1)(2)(MeOH)(2)](ClO4)(2) (1) and trans-[Cu(L-2)(2)(ClO4)(2)].2MeCN (2) (L-1=3-(2-pyridyl)-4-phenyl-5-(2-thienyl)-1,2,4-triazole, L-2=3-(2-pyridyl)-4-(p-chlorophenyl)-5-(2-thienyl)-1,2,4triazole), were synthesized and structurally characterized by FT-IR, elemental analyses, single-crystal X-ray crystallography and powder X-ray diffraction. Both 1 and 2 crystallize in monoclinic system with a space group P2(1)/c. X-ray crystallography analysis reveals that the copper ion in 1 and 2 sits in a distorted octahedral environment [CuN4O2] with two MeOH in the trans-position in 1 but two ClO4- in the trans-position in 2. Each L ligand in the equatorial plane adopts a chelating bidentate mode through the pyridyl N atom and one triazole N atom, while the thienyl group does not coordinate. 2 contains two MeCN guest molecules which produce pi-pi stacking interactions with the triazole ring. In 1 and 2 there are some intermolecular O-H...O, C-H...O and C-H....N hydrogen bonds and C-H...pi interactions, linking the mononuclear complexes to form a 3D framework.