Inorganic Chemistry, Vol.51, No.1, 88-97, 2012
Syntheses, Characterization, and Magnetic Studies of Copper(II) Complexes with the Ligand N,N,N',N'-Tetrakis(2-pyridylmethyl)-1,3-benzenediamine (1,3-tpbd) and its Phenol Derivative 2,6-Bis[bis(2-pyridylmethyl)amino]-p-cresol] (2,6-Htpcd)
The copper(II) complexes [Cu-4(1,3-tpbd)(2)(H2O)(4)(NO3)(4)](n)(NO3)(4n)center dot 13nH(2)O (1), [Cu-4(1,3-tpbd)(2)(AsO4)(ClO4)(3)(H2O)](ClO4)(2)center dot 2H(2)O center dot 0.5CH(3)OH (2), [Cu-4(1,3-tpbd)(2)(PO4)(ClO4)(3)(H2O)](ClO4)(2)center dot 2H(2)O.0.5CH(3)OH (3), [Cu-2(1,3-tpbd)-{(PhO)(2)PO2}(2)](2)(ClO4)(4) (4), and [Cu-2(1,3-tpbd){(PhO)PO3}(2)(H2O)(0.69)-(CH3CN)(0.31)](2)(BPh4)(4)center dot Et2O center dot CH3CN (5) [1,3-tpbd=N,N,N',N'-tetrakis(2-pyridylmethyl)-1,3-benzenediarnine, BPh4- = tetraphenylborate] were prepared and structurally characterized. Analyses of the magnetic data of 2, 3, 4, and [Cu-2(2,6-tpcd)(H2O)Cl](ClO4)(2) (6) [2,6-tpcd = 2,6-bis[bis(2-pyridylmethyl)amino]-p-cresolate] show the occurrence of weak antiferromagnetic interactions between the copper(II) ions, the bis-terdentate 1,3-tpbd/2,6-tpcd, mu(4)-XO4 (X = As and P) mu(1,2)-OPO and mu-O-phenolate appearing as poor mediators of exchange interactions in this series of compounds. Simple orbital symmetry considerations based on the structural knowledge account for the small magnitude of the magnetic couplings found in these copper(II) compounds.