The kinetics of the reaction of boric acid with salicylic acid

Abstract

Salicylic acid forms a 1:1 complex with boric acid, the reaction involving both the fully protonated ligand, and the salicylate ion. The kinetics of this reaction have been studied by the stopped-flow method. The stability constant for the reaction involving salicylate ion has been calculated from measurements of the absorbances of solutions at equilibrium and is the same as that obtained from the kinetic data. The kinetic results at pH values in the range 3.45–4.63 suggest that, when salicylic acid is the ligand, the complex is formed in two steps. A similar process may also occur with salicylate ions.

The kinetics of the reactions of boric acid with 5-substituted salicylate ions

“…Under the conditions used in the stopped-flow experiments, concentration changes are too small to be measured at low pH values where the salicylic acids are undissociated (7). For this reason, the present studies have been carried out at pH > 5, where the only reactants present in significant amounts are boric acid and salicylate ions.…”

“…Boric acid was Fisher Certified flow method. A previous study (7) has shown that, at Reagent. All mGe$als were dried in vacuo over phosphorus pH 5.29, the first-order rate constants are indepen-pentoxide.…”

DNA Binding and Cleavage Activities of Na[B(Glu)(OH)2]·2H2O, Na[B(Cit)(OH)2]·2H2O, Li[B(Sal)(OH)2], and Mg[B(Sal)(OH)2]·2H2O Complexes

“…The UV-visible spectra of the samples were obtained on microplate spectrophotometer (Epoch BioTech) with the Thermo Scientific Varioskan Flash spectral scanning method. (4) were synthesized as previously described [1]; the synthesized metal complexes and ligand were specified by chemical analysis, melting point measurements, thermal analysis, FT-IR analysis, 1H-NMR and 13 C-NMR analysis, 13 C MAS NMR analysis, 11 B MAS NMR, crystallographic studies, and ultraviolet-visible (UV-vis) physicochemical characterization [1].…”

“…There are efforts to put together boron into various biologically active molecules for nutritional and medicinal applications. Salicylic acid is a well-known complexing ligand with boric acid (Scheme 1(b)) [12,13]. Several bis-salicylatoborate complexes have been reported in the literature [14][15][16][17][18][19][20][21][22].…”

Synthesis, structure characterization, photoluminescence properties and TD–DFT calculations for two new borates

“…Salicylic acid (2-hydroxybenzoic acid) is formally a -hydroxy acid where the -OH group is adjacent to the carboxylic acid group. These groups make salicylic acid an interesting ligand in coordination chemistry; it is a well-known complexing agent with boric acid (Yang et al, 2011;Tang & Huang, 2009;Li & Liu, 2006;Queen, 1977;Bö eseken & Niks, 1940;Bö eseken & Meulenhoff, 1924) and can participate in hydrogen bonding to other molecules. We have applied the process of self-assembly of organic and inorganic moieties under mild and aqueous solution conditions and obtained two new borates with organic amines, namely diethylammonium bis(2-oxidobenzoato-2 O 1 ,O 2 )borate, (1), and propylammonium bis(2-oxidobenzoato-2 O 1 ,O 2 )borate, (2).…”