Bond Dissociation Energies of Solvated Silver(I)−Amide Complexes: Competitive Threshold Collision-Induced Dissociations and Calculations

Abstract

Using competitive threshold collision-induced dissociation (TCID) measurements, experimental bond dissociation energies have been evaluated for the water, methanol, and acetonitrile adducts of silver(I)-amide complexes. The influence of the solvent molecules on the binding energy of silver(I) to acetamide, N-methylacetamide, and N,N-dimethylacetamide was investigated. Experimental results show that solvents decrease the amide binding energy by 4-6 kcal mol(-1). Using density functional theory (DFT), binding energies were evaluated using nine functionals, after full geometry optimizations with the ECP28MWB basis set for silver and the 6-311++G(2df,2pd) basis set for the other atomic constituents of the ligands. In addition, calculations employing the DZVP basis set for Ag and DZVP2 for C, H, N, and O atoms at the B3LYP and MP2 levels of theory were used to investigate the influence of the basis set on the theoretical bond energies. A comparison of the experimental and theoretical silver(I)-ligand bond dissociation energies enables an assessment of the limitations in the basis sets and functionals in describing the energetics of the metal-solvent interaction and the metal-amide interaction. No single functional/basis set combination was found capable of predicting binding energies with a sufficiently high level of accuracy for the silver(I)-amide solvent complexes.

Deconstructive fluorination of cyclic amines by carbon-carbon cleavage

“…Furthermore, downfield shifts of NMR resonances of 1a were observed in the 1 H NMR spectra upon addition of AgBF 4 (fig. S3), suggesting the binding of Ag(I) to the amide moiety of 1a (36, 37). On the basis of these NMR experiments, we propose a mechanism that involves initial coordination of Ag(I) to 1a , followed by single-electron oxidation by Selectfluor to form Ag(II) and radical dication 5 (Eq.…”

Computational Study on Homolytic Bond Energies of the Ag–X (X = C, O, and H) Complexes and Hammett-Type Analysis of Reactivity

“…For example, B3LYP/ECP28MWB was utilized by the Siu group to evaluate the binding energies between Ag(I) and neutral ligands (such as H 2 O, CH 3 OH, CH 3 CN, and amide) with a precision of 4–6 kcal/mol. 9 The O’Hair group 10 found that M06 could accurately estimate the Ag–CH 3 bond energies, and a series of Ag–C alkyl bonds were investigated using this method. Furthermore, the Hii group 11 and the Chattaraj 12 group have studied the bond energies of Ag–carbene and Ag–bipyridine and neutral small molecule ligands such as H 2 , N 2 , CO, and CO 2 using BP86 and PBE0, respectively.…”

Development of silver/α-lactalbumin nanocomposites: a new approach to reduce silver toxicity

“…Silver-based antimicrobial agents are traditional antiseptics with broad-spectrum antimicrobial activities both against Grampositive and Gram-negative micro-organisms [1][2][3][4][5][6][7][8][9], including multiresistant bacterial strains [1,4]. However, their current applications are still rigorously restricted to specific medical conditions (e.g.…”

“…Various silver and silver compounds were incorporated into different forms of chitosan matrices [5,6]. Polyamides and proteins are another category of biopolymers that contain abundant amide groups, however only a few studies have focused on the formation of silver-amide chelating complex [7][8][9].…”