Molecular structures and supramolecular association of chlorodiorganotin(IV) complexes with bis- and tris-dithiocarbamate ligand Hugo Tlahuext * , Reyna Reyes-Martínez, Gabriela Vargas-Pineda, Marcela López-Cardoso * , Herbert Höpfl Centro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Col. Chamilpa, C.P. 62209, Cuernavaca, Morelos, Mexico article info Article history: Received 26 August 2010 Received in revised form 24 September 2010 Accepted 24 September 2010 Keywords: Dithiocarbamate Cavitands Self assembly Supramolecular chemistry Tin abstract Two series of di and trinuclear chlorodiorganotin(IV) complexes derived from bis- and tris-dithiocar- bamate ligands have been prepared and structurally characterized. The dinuclear complexes 1e2 of the composition {(R 2 SnCl) 2 (bis-dtc)} (1 ,R ¼ Me; 2,R ¼ n Bu) have been obtained from R 2 SnCl 2 (R ¼ Me, n Bu) and the triethylammonium salt of N,N 0 -dibenzyl-1,2-ethylene-bis(dithiocarbamate). The trinuclear complexes 3e9 with the general formula {(R 2 SnCl) 3 (tris-dtc)} 3,R ¼ Me, tris-dtc ¼ tris-dtc-Me; 4, R ¼ Me, tris-dtc ¼ tris-dtc- i Pr; 5,R ¼ Me, tris-dtc ¼ tris-dtc-Bn; 6,R ¼ n Bu, tris-dtc ¼ tris-dtc-Me; 7 , R ¼ n Bu, tris-dtc ¼ tris-dtc- i Pr; 8,R ¼ n Bu, tris-dtc ¼ tris-dtc-Bn; 9,R ¼ t Bu, tris-dtc ¼ tris-dtc-Me) were prepared from R 2 SnCl 2 (R ¼ Me, n Bu, t Bu) and the potassium dithiocarbamate salts of (tris[2-(methyl- amino)ethyl]amine) (tris-dtc-Me), (tris[2-(isopropylamino)ethyl]amine) (¼tris-dtc- i Pr) and (tris[2- (benzylamino)ethyl]amine) (¼tris-dtc-Bn). Compounds 1e9 have been analyzed as far as possible by elemental analysis, FAB þ mass spectrometry, IR and NMR ( 1 H, 13 C, 119 Sn) spectroscopy, and single-crystal X-ray diffraction analysis. The solid state and solution studies showed that the dtc ligands are coordi- nated to the tin atoms in the anisobidentate manner. In all cases the metal centers are five-coordinate. The coordination geometry is intermediate between square-pyramidal and trigonal-bipyramidal coor- dination polyhedra with s-values in the range of 0.32e0.53. For the members of each series charac- terized in the solid state by X-ray diffraction analysis, different molecular conformations were found. The crystal structures show the presence of CeH/Cl, CeH/S, CeH/p,S/Cl, S/S, Cl/Sn and S/Sn contacts. Ó 2010 Elsevier B.V. All rights reserved. 1. Introduction Non-covalent interactions are fundamental for supramolecular chemistry, drug design, protein folding, crystal engineering and other areas of molecular science [1]. The non-covalent intermolecular interactions that lead to crystal formation can typically be divided into strong, moderate and weak interactions, although the demarcations between them are not sharp. Hydrogen-bonding is a classical example of a strong or moderate, but generally specific and highly directional intermolecular interaction. However, weaker interactions such as CeH/X, CeH/p, p/p,X/X and X/Y (X ¼ O, N, S, F, Cl, Br, I) contacts are also of considerable importance for the stabilization of molecular solids [2].CeH/X hydrogen bonds have been shown to be of great importance for molecular recognition processes [3], the reactivity and structure of biomolecular species [4], the stabilization of inclusion complexes [5], crystal engineering [6], conformational isomerism [7] and the properties of ionic liquids [8]. So far, little is known about supramolecular assemblies derived from organometallic building blocks. Indeed, there are only few useful candidates for this purpose and among these are organotin systems that have shown to be particularly interesting [9]. Tin continues to attract significant attention, owing to its many and varied applications in fields such as agriculture, biology, catalysis, organic synthesis, etc. [10]. An important class of compounds are mono-, di-, and triorganotin dithiocarbamates, which have been studied in solution and by single-crystal X-ray diffraction analysis [11]. The uses and potential utility of these compounds have been reviewed by Tiekink in 2008 [12]. Recently, we reported on the spectroscopic and structural char- acterization of dinuclear diorganotin(IV) dithiocarbamate macro- cycles, as well as trinuclear diorganotin cavitands and capsules, * Corresponding authors. Tel./fax: þ52 777 3297997. E-mail addresses: tlahuext@ciq.uaem.mx (H. Tlahuext), marce@ciq.uaem.mx (M. López-Cardoso). Contents lists available at ScienceDirect Journal of Organometallic Chemistry journal homepage: www.elsevier.com/locate/jorganchem 0022-328X/$ e see front matter Ó 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.jorganchem.2010.09.061 Journal of Organometallic Chemistry 696 (2011) 693e701