Syntheses of Chelating Tetrazole-Containing Ligands and Studies of Their Palladium(II) and Ruthenium(II) Complexes

Abstract

Eleven chelating tetrazole -containing ligands have been synthesized, and their complexes with palladium(II) and ruthenium(II) prepared. Proton n.m.r. spectroscopy, electronic absorption spectroscopy and cyclic voltammetry have been used to study the nature of the metal-ligand interactions in these complexes. The negatively charged tetrazolate group is shown to be a strong electron donor with very different properties to those of the protonated or alkylated tetrazole group. This leads to pH control of the properties of transition metal complexes containing such ligands.

3,6‐Di(2‐pyridyl)‐1,4,2,5‐dioxadiazine and a Silver Coordination Polymer with an Unprecedented Metallosupramolecular Topology

“…All attempts to produce crystals of this product suitable for X-ray structure determination were in vain. Pleasingly, however, reaction of 6 with silver tetrafluoroborate produced the 1:1 M:L complex AgL(BF 4 ) (8), [25] that upon recystallization from acetonitrile underwent reorganisation to a 1:2 complex AgL 2 (BF 4 ), (9), which did furnish X-ray quality crystals.…”

“…For example, we have reported a number of chelating ligands that contain tetrazole, [8] furoxan, [9] benzotriazole, [10] benzisoxazole, [11] 1,2,5-thiadiazole [12] and 1,2,3-chalcogenadiazole groups. [13] Most recently, we described a study of the binuclear ruthenium() complexes of 3,4-di(2-pyridyl)-1,2,5-oxadiazole (5), [14] which revealed remarkably strong metal-metal interactions, the magnitude of which was dependent on the specific diastereoisomer.…”

Pyridyl Azolate Based Luminescent Complexes: Strategic Design, Photophysics, and Applications

“…Surprisingly, the coordination chemistry involving the tetrazoles has Scheme 5.3 Reaction sequence for the preparation of pyridyl triazole and the molecular structures of relevant triazole and tetrazole ligands. received little attention in the past, despite the fact that tetrazole is the most acidic of all the azoles, with p K a = 4.89, and readily deprotonates to the tetrazolate ion [24] . However, a recent report by Sharpless [25] clarifi ed their possible explosive nature during manipulation and, in the meantime, provides an effi cient preparation method employing 2 -cyanopyridine and sodium azide in aqueous media.…”

An Efficient Protocol for Facile Synthesis of New 5-Substituted-1H-Tetrazole Derivatives Using Copper-Doped Silica Cuprous Sulfate (CDSCS) as Heterogeneous Nano-Catalyst

“…1,2 Tetrazoles are extensively applied in different industries as instance: stabilizers in photography and photo imaging, 3,4 explosives in rocket propellants, [5][6][7] chelating agents in coordination chemistry, 8,9 plant growth regulators, herbicides, fungicides in agriculture, 3,10 and anti-wears and frictions in lubricants. 11 Additionally, tetrazoles can be served as bioisosteres for the carboxylic acids.…”