Metallosupramolecular Compounds Based on Copper(II/I) Chloride and Two Bis-Tetrazole Organosulfur Ligands

Abstract

The present work assesses the ability of two flexible bis-tetrazole organosulfur ligands to build up different metallosupramolecular compounds based on the analysis of the different supramolecular interactions. The reaction of copper(II) chloride dihydrate with the N,N’-donor dithioether ligands bis(1-methyl-1H-tetrazole-5-ylthio)methane (BMTTM) and 1,2-bis(1-methyl-1H-tetrazole-5-ylthio)ethane (BMTTE) was investigated using different synthetic methods. Four compounds have been obtained as single crystals: two pseudopolymorphic 1D Cu(II) coordination polymers with the ligand BMTTM, a 2D Cu(II) coordination polymer and a discrete Cu(I) tetramer with the BMTTE ligand. The effects of the weak interactions on the crystal packing and the Hirshfeld surfaces of the structures were analyzed to clarify the nature of the intermolecular interactions.

From Cu(i) and Cu(i)–Cu(ii) mixed-valence clusters to 2D Cu(ii) and Cu(i) coordination polymers supported by a flexible bis-tetrazole organosulfur ligand

“…The reactivity of the CuBr 2 /bmtte system (Scheme 1) was studied using different stoichiometric ratios, synthetic methods, times, temperatures and solvents to obtain a broad overview of the system. In this way, four single crystals were isolated and structurally characterised: two 2D polymorphs (1m and 1t) of 2 1 Cu 2 Br 4 (bmtte) and two 0D polynuclear complexes, namely the trinuclear [Cu 3 Br 4 (bmtte) 2 ] (2) and the tetranuclear [Cu 2 Br 2 (bmtte)] 2 (3). Efforts were made to achieve control over the preparation of compounds 1-3 (Scheme 1) by careful investigation of the synthetic processes and variables.…”

“…In this sense, we have recently focused on using bis-tetrazole organosulfur ligands to introduce more donor atoms, which could be useful to manipulate the structural conformation of the resulting copper complexes. 3 The self-assembly of a metal and a ligand can produce numerous compounds that have different structures and properties. In particular, the use of a flexible ligand can stabilise different ligand conformations to yield polymorphic supramolecular isomers, which occur as different crystal forms of the same chemical species but with different crystal packing, space groups and unit cell parameters.…”

“…5 Our group has a great deal of experience in investigating the utility of flexible dithioether ligands to form metallosupramolecular compounds with copper(II) halide salts under different synthetic conditions and we have isolated compounds of different dimensionalities. 3,[6][7][8][9][10] Among this kind of ligand, 1,2-bis(1-methyl-1H-tetrazole-5-ylthio)ethane (bmtte) is a multifunctional twisted organic ligand composed of two methyltetrazole groups separated by a flexible organosulfur bridge (-S-CH 2 -CH 2 -S-) that can rotate and adjust the direction of the coordinating nitrogen atoms. In the field of metallosupramolecular chemistry, this ligand is of interest because the tetrazole organosulfur derivatives contain multiple atoms that can facilitate simultaneously the coordination to one or more metal centres and the interaction with their surroundings through diverse weak interactions.…”

“…In the work reported here, the coordinative behaviour of 1,2-bis(1-methyl-1H-tetrazole-5-ylthio)ethane (bmtte) towards copper(II) bromide was explored. The resulting trinuclear [Cu 3 Br 4 (bmtte) 2 ] (2), tetranuclear [Cu 2 Br 2 (bmtte)] 2 (3) and polymeric 2 1 Cu 2 Br 4 (bmtte) (1) were obtained by different synthetic methods. In addition, in this structural study the formation of two polymorphic forms of the 2D polymer 1 was observed.…”

Supramolecular Chemistry in the 3rd Millennium

“…For example, close S...S contacts. Carballo, Belén Lago and coworkers illustrate the different supramolecular interactions that predominate in the structures of the copper(II) coordination compounds of two flexible bis-tetrazole organosulfur ligands [9]. Copper(II) coordination compounds containing Schiff base ligands have been designed by Marques Netto and coworkers as model systems to realize allosteric behavior by regulating the equilibrium between monomeric and dimeric species [10].…”