Synthesis and structural characterization of mixed-metal complexes of CuI with MOS3 cores (M = Mo, W) and of an unusual polymeric AgI/mercaptoimidazole complex with five different AgI coordination environments

Abstract

Reaction of (NH(4))(2)[MO(2)S(2)] (M = Mo or W) with KI, CuCl and 1,3-diazepane-2-thione (Diap) in acetone affords air- and moisture-stable mixed-metal cluster compounds [MOS(3)(CuDiap)(3)]I (1 and 2). Attempts to produce [WS(4)Ag(2)(Mim(Ph))(4)] (Mim(Ph) = 2-mercapto-1-phenylimidazole) led to the unexpected polymeric compound [Ag(5)I(5)(Mim(Ph))(4)](n) (4), subsequently obtained from a rational direct reaction between AgI and Mim(Ph) in chloroform. The complexes have been characterized by IR, (1)H and (13)C NMR spectroscopy, and single-crystal diffraction. 1 and 2 have crystallographic threefold rotation symmetry, with an incomplete distorted cube MS(3)Cu(3) core bearing terminal oxo and Diap ligands on M and Cu, respectively. The cube vertex opposite M is empty, giving an overall +1 cationic cluster and a separate I(-) anion too distant from the three Cu atoms to be considered as covalently bonded and resulting in discrete ion pairs in the crystal structures. This arrangement is different from previously reported related OMS(3)(CuL)(3)X complexes (L = monodentate ligand, X = halide), in which X, when present, is directly bonded to one, two or three Cu atoms. 4 has a one-dimensional polymeric chain structure in which silver displays five different approximately tetrahedral coordination environments, iodide ions serve as μ(2), μ(3) and μ(4) bridges, and the thione ligands are each either terminal or bridging. This unusually complex structure for a relatively simple chemical formula represents only the fifth example of a complex (AgI)(n)L(m) in which L is a neutral S-donor ligand, and the five structures display a wide range of individual features. In all three of the new structures, N-H···S and/or N-H···I hydrogen bonds are found.

Metal-to-Ligand Ratio As a Design Factor in the One-Pot Synthesis of Coordination Polymers with [MS4Cun] (M = W or Mo, n = 3 or 5) Cluster Nodes and a Flexible Pyrazole-Based Bridging Ligand

“…While Cu–S and Cu–N bond lengths span relatively small ranges [2.252(3)–2.303(3) Å and 1.924(10)–1.969(9) Å respectively], there is considerably greater spread in the bonded Cu–I distances [2.9323(19)–3.3311(16) Å]; closer inspection shows that the μ 3 bonding of I(1) is much more symmetrical (range < 0.05 Å) than that of I(2) (range almost 0.4 Å), which forms one long and two short bonds, tending slightly toward a μ 2 situation like that found for I(3) in the cluster of complex 1 . We have previously discussed the wide range of bonding asymmetry observed for I atoms in (O/S)MS 3 Cu 3 I pseudocubane clusters, and the degree of asymmetry found for I(2) here is much less extreme than in several other cases. It does, however, represent the most significant difference between the two crystallographically distinct clusters in the structure of 2 .…”

Two polymorphs of tetraethylammonium [hydrogen tris(3,5-dimethylpyrazolyl)borato]di-μ2-sulfido-disulfido(η2-tetrasulfido)ditungsten(V) withZ′ = 1 and 2

“…In a long-term research project investigating mixed-metal cluster compounds with thiometallate cores (see, for example, Beheshti et al, 2007Beheshti et al, , 2008Beheshti et al, , 2011, we treated (Et 4 N)[Tp*WS 3 ] [Tp* À is hydrogen tris(3,5-dimethylpyrazolyl)borate, an established tripodal ligand] with AgI in acetonitrile solution. Elemental analysis and electronic and vibrational spectroscopy of the crude product indicated a successful synthesis of the intended product (Et 4 N)[Tp*WS 3 (AgI)] in a type of reaction we have used many times previously; however, attempted recrystallization from acetonitrile solution by vapour diffusion of diethyl ether led to decomposition and the unexpected isolation of the title complex, (Et 4 N)[Tp*W 2 S 2 -( 2 -S) 2 (S 4 )], (I), which was identified by crystal structure determination.…”

Three- and four-coordinate Ag(I) complexes of crotonate and bis(benzimidazole)-2-oxapropane ligands: syntheses, crystal structures, DNA-binding studies and antioxidant activities

“…The compounds of Ag(I) with multidentate N-donor ligands have attracted interest for a number of reasons. The absence of crystal field stabilization for the d 10 monovalent silver cation, coupled with its ability to tolerate a wide range of coordination geometries (with coordination numbers spanning 2-7), leads to considerable variation in the geometry and connectivity of the networks that can be formed when Ag(I) centers act as connectors [14,15]. Their various biological applications have also attracted attention [16].…”