A Theoretical Case Study of Substituent Effects and Microsolvation on the Binding Specificity of Crown Ethers

Autor:	Rick A. Kendall, David Feller, Mark A. Thompson
Rok vydání:	1997
Předmět:	chemistry.chemical_compound chemistry Stereochemistry Computational chemistry Yield (chemistry) Substituent Physical and Theoretical Chemistry Perturbation theory Alkali metal Selectivity Derivative (chemistry) Cation exchange reaction Binding selectivity
Zdroj:	The Journal of Physical Chemistry A. 101:7292-7298
ISSN:	1520-5215 1089-5639
Popis:	Hartree−Fock and second-order perturbation theory calculations were performed on complexes of a single alkali metal cation and a recently synthesized derivative of 18-crown-6 that locks the crown macrocycle into a D3d-like configuration. Unlike 18-crown-6, which binds K+ with a 100-fold selectivity over Na+, the derivative prefers Na+ by a factor of 4:1. Calculations on a simple K+ ↔ Na+ cation exchange reaction indicate a small shift in binding preference in favor of Na+, but the inherent uncertainty in the theoretical treatment makes an unequivocal conclusion difficult. The effects of two microsolvating waters attached to the cation/s18-crown-6 complex and up through four microsolvating waters bound to 18-crown-6 were considered. The levels of theory used in this study were similar to those previously found to yield binding preferences in qualitative agreement with liquid-phase experimental data. To the best of our knowledge, this work, which involved more than 800 basis functions for several complexes,...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::651255cd0b59dfc0508e308e4db231f2 https://doi.org/10.1021/jp971509s Zobrazit plný text záznamu