Two forms of a copper(II) complex of 3-phenyl-5-(2-pyridyl)-4-(4-pyridyl)-4H-1,2,4-triazole: a six-coordinate monomer versus a five-coordinate polymer

摘要: The reaction of the new bidirectional ligand 3-phenyl-5-(2-pyridyl)-4-(4-pyridyl)-4 H -1,2,4-triazole (pyppt) with Cu(ClO 4 ) 2  · 6H O in a 2:1 molar ratio EtOH affords complex [Cu II (ClO ] · H ( 1 as microcrystalline turquoise solid. Recrystallisation from MeCN by vapour diffusion Et gives blue crystals monomeric octahedral ] · MeCN ). In contrast, addition to solution followed slow evaporation yields five-coordinate polymeric {[Cu ](ClO  · EtOH} ∞ 3 structures both complexes have been determined single crystal X-ray diffraction.