Sintese, análise estrutural e supramolecular de complexos triazenido de Ag(I), Cd(II) E Zn(II)

Abstract

In this work was synthesized and determined the crystal and molecular structure of two silver triazenide complexes, two cadmium triazenide complexes and a zinc triazenide complex. The complexes {Ag[C12H9N2NNNC6H4(NO2)](C5H5N)}2 (1) and {Ag[C6H3Br2NNNC6H3Br2](C5H5N)}2 (2) crystallize in the monoclinic crystal system, space group P2(1)/c and P2(1)/n respectively. The refinement of those structures converge to de follow discordance indexes R1 = 0,0473 and 0,0503 respectively. The structures of complexes (1) and (2) consist of binucleated neutral silver complexes, centrosymmetric and acentric, respectively, in which metal ions are coordinated by two desprotonated molecules of the ligand (L1) and (L2), respectively, and a neutral molecule of the pyridine. Both complexes (1) and (2) show Ag···Ag interactions allowing an expansion of the coordination geometry of distorted tetrahedral from the distorted T in the case of complex (1) and distorted T to a distorted pyramid with square base in the case of complex (2). In addition, the complex (1) shows the formation of 2-D supramolecular arrangement, forming centrosymmetric dimers through interactions Ag-arene- η2, η2 π and hydrogen centrosymmetric bonding C-H···O and formation of supramolecular 3-D to the complex (2) through non-classic centrosymmetric hydrogen bonds C-H···Mi, weak interactions Br2···Br2ii and Br3···Br3ii . The cadmium complex Cd[(C6H3Br2NNNC6H3Br2)(C5H5N)]2 (3) and [Cd(C6H3Br2NNNC6H3NO2OCH3)2(C5H5N)2] (4) are mononucleated. The complex (3) present a distorted octahedral geometry of coordination and the complex (4) present a distorted tetrahedral geometry of coordination. They crystallized on the monoclinic and triclinic crystal system and P2(1)/c and P(-1) space group, respectively. The refinement of those structures converge to the discordance indexes R1 = 0,0310 and 0,0693 respectively. The structure of the complex (3) consists of a neutral mononuclear complex of cadmium, centrosymmetric, in which the ion metal is hexacoordenated, presenting a coordination geometry distorted octahedral with two molecules of ligand (L2) connected in a bidentate chelating and two molecules of pyridine trans. The structure of the complex (4) consists of a neutral mononuclear complex of cadmium, acentric, in which the ion metal is tetracoordenated, with distorted tetrahedral coordination geometry with two molecules of ligand (L3) linked monodentate and two molecules of pyridine. The complex (3) provides 2-D supramolecular arrangement according to the non-classical hydrogen bonds centrosymmetric C16-H16···Bri and Br2···Br4ii and the complex (4) shows 2-D supramolecular arrangement via hydrogen bonds non-classical centrosymmetric C-H···O. The zinc complex Zn(C6H3Br2NNNC6H3Br2)2(C5H5N)2] (5), has distorted tetrahedral coordination geometry similar to the complex (4) since it comprises the ligand (L3), which is coordinated in the same way as observed in the complex (4), and crystallizes in the triclinic crystal system, space group P (-1). The refinement of this structure converged to the discordance indexes R1 = 0.0757. The complex (5) shows 2-D supramolecular arrangement through no-classical hydrogen bonds centrosymmetric C-H···O.