Project Details Critical compilation of acid pKa values in polar aprotic solvents

Project No.:
2015-020-2-500
Start Date:
01 May 2016
End Date:

Objective

The objective is to summarize and critically evaluate the data on ionization constants of acids (pKa data) available in a selection of polar aprotic solvents, which are either (1) the most popular solvents for pKa determination or (2) have properties specifically suitable for determination of pKa values of certain compound classes. The outcome of the work will be a compilation together with critical evaluation of pKa values (published as an article in Pure and Applied Chemistry). The tentative solvent selection is the following: MeCN, DMSO, DMF, pyridine, acetone. In the polar aprotic solvents almost full coverage of measured compounds will be possible.

Description

The objective is to summarize and critically evaluate the data on ionization constants of acids (pKa data) available in a selection polar aprotic of solvents, which are either (1) the most popular solvents for pKa determination or (2) have properties specifically suitable for determination of pKa values of certain compound classes. The outcome of the work will be a compilation together with critical evaluation of pKa values (published as article in Pure and Applied Chemistry). The tentative solvent selection is the following:

MeCN, DMSO, DMF, Pyridine, Acetone.

In the polar aprotic solvents almost full coverage of measured compounds will be possible.

Progress

Feb 2021 update – Assembling the compilation is almost finished. It now includes 9347 pKa values in seven dipolar non-hydrogen bond donor solvents (dimethyl sulfoxide, acetonitrile, N,N-dimethylformamide, pyridine, acetone, propylene carbonate, tetrahydrofuran) for 4913 neutral acids collected from around 779 original works published during the last sixty years. The data have been critically evaluated on the basis of pre-defined quality criteria and depending on situation, kept as they are (around 5300 values), marked doubtful (around 1800 values) or corrected (around 2200 values). In order to enable automated data processing and mining, the data are presented as an XLSX file, together with coded structures, compound class qualifiers and comments.

The compilation was submitted to IUPAC for “pre-review” in Dec 2020.

The work in progress now is polishing the dataset, checking for errors and elaborating the structural codes.

Page last update 14 Apr 2021