Influence of Water Content on Basicities in Acetonitrile

被引：9

作者：

Kaupmees, Karl ^{[1
]}

Kaljurand, Ivari ^{[1
]}

Leito, Ivo ^{[1
]}

机构：

[1] Univ Tartu, Inst Chem, EE-50411 Tartu, Estonia

来源：

JOURNAL OF SOLUTION CHEMISTRY | 2014年 / 43卷 / 07期

关键词：

pK(a); Water residue; Charge delocalization; COSMO-RS; Non-aqueous solvent; GAS-PHASE; COSMO-RS; SCALE; BASES; CONSTANTS; ENERGIES; ACIDITY; AMINES;

D O I：

10.1007/s10953-014-0201-4

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The influence of water content at impurity level (5-10,000 ppm) in acetonitrile, on the changes in relative basicity differences (Delta pK (a) values) of 13 pairs of bases, was studied both experimentally and computationally (COSMO-RS). The Delta pK (a) values involving smaller bases with localized charge in the cationic form were found to be more affected. A computational parameter, weighted average negative sigma (WANS), was proposed to quantify the charge delocalization in cations and succeeded in describing the observed changes of Delta pK (a). The results validate the previously published basicity scale in acetonitrile with respect to solvent dryness and give guidelines for better experimental planning.

引用

页码：1270 / 1281

页数：12

共 24 条

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