Controlling the ligating behaviour of biologically important p-hydroxybenzoate towards copper(II) by the use of nitrogen bases: synthesis, characterization and single crystal X-ray structure determination of [trans-Cu(en)2(H20)2](L1)2.2H20 and [cis-Cu(L1)2(L2)2] where en=ethylenediamine, L1=p-hydroxybenzoate, L2= 3-picoline

Two new copper (II) complex salts have been prepared and characterized by elemental analysis, spectroscopic techniques and conductance measurements. In complex 1 copper (II) is coordinated to four nitrogen atoms and two water molecules while in complex 2 copper (II) is ccordinated to four oxygen atoms and two nitrogen atoms.

Two new copper(II) complex salts of composition [trans-Cu(en)2(H2O)2](p-hydroxybenzoate )2 · 2H2O (1) and [cis-Cu(p-hydroxybenzoate)2(3-picoline)2] (2) have been prepared. The newly synthesized complex salts have been characterized by elemental analyses, spectroscopic techniques (UV/visible, IR and EPR) and conductance measurements. The complex salt 1 crystallizes in the monoclinic space group P21/c having cell dimensions a = 11.8907 (2), b = 9.4443 (2), c = 10.8489 (3)Å, β = 100.340 (1)°, V = 1198.54 (5) Å3, Z = 2 and complex salt 2 crystallizes in the monoclinic space group P2/c having cell dimensions a = 9.9924 (3), b = 10.6862 (4), c = 11.6493 (3)Å, β = 108.588 (2)°, V = 1179.03 (6)Å3, Z = 2. X-ray structure determination revealed an ionic structure consisting of one complex cation [trans-Cu(en)2(H2O)2]2+ , two [C7H5O3]- ions, two lattice water molecules in 1 and coordinated structure consisting of two p-hydroxybenzoate and two 3-picoline units attached to copper center in 2. In co...