Copper complexes with quadridentate bis(pyrazolyl)thioether amine and tris(pyrazolyl)amine ligands. Structural characterization of the complexes [Cu(NCS)(tpea)][Cu(NCS)2] and [CuCl(bdma)]Cl·2H2O

Abstract

Copper complexes with the two tripod quadridentate ligands tris(2-pyrazolylethyl)amine (tpea) and bis[2-(3′,5′-dimethylpyrazolyl)ethyl](2-methylthioethyl)amine (bdma) having N₄ and N₃S donor sets, respectively, have been synthesized and assigned the following formulae: [CuX(tpea)] BPh₄(X = Cl, Br, or NCS), [CuCl(tpea)]₂[CuCl₄], [Cu(NCS)L][Cu(NCS)₂](L = tpea or bdma), [Cu(NCS)(bdma)]BPh₄·(CH₃)₂CO, [CuCl(bdma)]Cl·2H₂O, and [CuBr(bdma)]₃[CuBr₃]Br·H₂O. The structures of [Cu(NCS)(tpea)][Cu(NCS)₂](1) and [CuCl(bdma)]Cl·2H₂O (2) have been solved by X-ray diffraction methods. Both compounds crystallize in the monoclinic space group P2₁/c with Z= 4 and unit-cell dimensions: (1), a=18.026(9), b= 8.847(4), c=16.302(7)Å, and β=113.18(5)°; (2),a=17.243(8),b=10.001(5), c=14.763(7)Å, and β= 109.52(6)°. The structure of complex (1) consists of isolated [Cu(NCS)(tpea)]⁺ cations, where the copper(II) atom is in an approximately trigonal-bipyramidal environment of five N atoms, and of layers formed by the [Cu(NCS)₂]^– anion, with pseudo-tetrahedral copper(I) atoms. The copper(II) atom in the [CuCl(bdma)]⁺ cation of (2) is in a square-pyramidal environment of one S, one Cl, and three N atoms.