Novel silver(I)-saccharinate complexes exhibiting Ag center dot center dot center dot pi and C-H center dot center dot center dot Ag close interactions with a new coordination mode of saccharinate

Abstract

Two novel silver(I) complexes, namely (Ag-2([mu(3)-sac)(2)(mu-nmpen)(n), (1) and [Ag(sac)(mpr)](2) (2) (sac = saccharinate; nmpen = N-methyl-1,3-propanediamine; mpr = 2-methyl-l-pyrroline) have been synthesized and characterized by IR spectra, thermal (TG, DTG and DTA) analysis and single crystal X-ray diffraction techniques. Complexes crystallize in the monoclinic system with the space group C2/c and P2(1)/c, respectively. In 1, Ag(l) ion exhibits a distorted tetrahedral geometry by tridentate mu(3)-bridging sac and mu(2)-bridging nmpen ligands. The sac ligand exhibits a new mu(3)-coordination mode by means of mu(2)-bridging O atom of sulfonyl group and N atom of imino group. Furthermore, complex 1 exhibits a two-dimensional polynuclear structure. In 2, the silver(1) ion is linearly coordinated by the N atoms of a sac and a mpr ligands, forming mononuclear species. The individual molecules are linked into dimers by Ag center dot center dot center dot C-sac (eta(1)) interactions between silver(I) ion and phenyl ring of the adjacent complex and these dimers are assembled into two-dimensional layered networks through weak Ag center dot center dot center dot Ag (3.507 angstrom), S=O center dot center dot center dot Ag (2.961 angstrom) and pi center dot center dot center dot pi interactions. The most interesting structural features of complexes is the presence of obvious C-H center dot center dot center dot M hydrogenbonding interactions between the Ag centers and H atoms of nmpen or mpr ligands. (C) 2010 Elsevier Ltd. All rights reserved.