Prediction of acid pK_a values in the solvent acetone based on COSMO‐RS

Abstract

In this contribution we extent the use of the conductor-like screening model for realistic solvation (COSMO-RS) to the prediction of pK a values in acetone, a commonly used dipolar aprotic solvent. For this, we calculated the Gibbs free energy of dissociation of 120 organic acids (nine acrylic acids, 87 benzoic acids, nine phenols, and 15 benzenesulfonamides) using COSMO-RS at the two levels BP-TZVP and BP-

Computational investigation of explicit solvent effects and specific interactions of hydroxypyrene photoacids in acetone, DMSO, and water

“…These calculations employ—in difference to those described in Section 2.2—geometries that are optimized with ε r = ∞ for COSMO. Details on COSMO-RS itself, 63–66,101 the difference between these two levels, 102 as well as the precise computational protocol for p K a 82,103–105 can be found elsewhere. Multiple conformers for both the acid and base species of the photoacids A – F (defined in Fig.…”

“…For p K a in acetone, the parameters for COSMO-RS were taken from ref. 82. Excited-state values are then obtained by adding the Δp K a from eqn (1) to the COSMO-RS ground-state p K a .…”

“…The previous approach for the theoretical spectroscopy will be extended to the new target solvent acetone. The calculated p K a in acetone based on recently determined linear free-energy relationship (LFER) parameters for COSMO-RS 82 in combination with Δp K a from calculated spectra will give access to the values of the photoacids A – F in acetone. These allow to judge and compare the thermodynamic possibility of ESPT of these different compounds in acetone.…”

Theoretical Study on the Photoacidity of Hydroxypyrene Derivatives in DMSO Using ADC(2) and CC2

“…38−42 COSMO-RS is an extension of the conductor-like screening model (COSMO) 43,44 to reintroduce specific solute−solvent interactions and it has been already successfully applied to pK a calculations in water, 45,46 dimethyl sulfoxide (DMSO), 45 acetonitrile, 47 and acetone. 48 Until today, only few examples of theoretical pK a * predictions are reported in the literature, using quantum chemical calculations 49−56 as well as molecular dynamics (MD) simulations with hybrid quantum-mechanics/molecular-mechanics (QM/MM) techniques. 57−60 Some theoretical studies on photoacids also attempt to directly address the ESPT process by modeling its reaction mechanism or providing information on the molecular factors governing photoacidity, e.g., the electronic structure.…”

Animal Comfort Studies in Natural Environment Reserves Integrating RS and GIS

“…This paper uses a maximum likelihood approach to classify land use/cover in nature reserves based on remotely sensed data, and uses a transfer matrix to study changes in feature class cover, with a focus on vegetation destruction in protected areas [9,10]. In this paper, the suitability of animal habitats in nature reserves is evaluated.…”