Potentiometric, 1H NMR and ESI-MS investigation on dimethyltin(iv) cation–mercaptocarboxylate interaction in aqueous solution

Abstract

The interaction between dimethyltin(IV) cation with three different mercaptocarboxylic acids (thiolactic, 3-mercaptopropanoic and thiomalic acids) was studied in aqueous solution by potentiometry, 1 H NMR spectroscopy and electrospray (ESI) mass spectrometry. The speciation model and equilibrium data were determined on the basis of potentiometric evidences, as well as the bonding sites by means of ESI mass spectrometry and the geometry of the species by 1 H NMR spectroscopy. The speciation profiles show the formation of different complex species, whose stabilities and formation percentages, in particular for the mononuclear mixed species, are high in a wide pH range. ESI mass spectrometry studies together with 1 H NMR investigations fully confirm the speciation model. The former also allows to propose a cyclic structure with O-Sn and S-Sn coordination, confirmed by MS/MS analysis; the latter indicates angles mostly matching with a Tbp arrangement around the metal.

Modeling the Solubility of Phenolic Acids in Aqueous Media at 37 °C

“…Vanillic (J&K Scientific, Beijing, China, 99%), syringic and gallic (Sigma Aldrich, St. Louis, MI, USA, ≥98% and ≥99%, respectively), p-coumaric (Sigma, St. Louis, MI, USA, ≥98%), ferulic and caffeic (Aldrich, St. Louis, MI, USA, 99%) acids were used without further purification. Sodium perchlorate and sodium chloride stock solutions were prepared and standardized according to previous works [56,57].…”

Thermodynamic data for Pb2+and Zn2+sequestration by biologically important S-donor ligands, at different temperatures and ionic strengths

“…[5][6][7] For this reason, in recent years we have undertaken a detailed study on the acid-base and binding properties of S-donor ligands against some metal and organometallic cations of environmental and biological relevance. [8][9][10][11][12][13][14][15][16] Here we extended the study to the interaction of some sulfur containing aminoacids (see Fig. 1) with a toxic metal, such us Pb 2+ , and an essential metal, such as Zn 2+ , recently studied by thermogravimetric analysis.…”

Interaction of Ampicillin and Amoxicillin with Mn2+: A Speciation Study in Aqueous Solution

“…In order to confirm the speciation model and the formation constants gained via potentiometry by spectroscopic techniques as already established for other systems [ 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ], spectrophotometric titrations on solutions containing Mn 2+ and Amp at t = 25 °C and I = 0.15 mol L −1 were performed under different concentration conditions. As an example, experimental spectra recorded on solutions containing Mn 2+ and Amp at C M = 0.05 mmol L −1 and C L = 0.05 mmol L −1 , were depicted in Figure 3 .…”