Article ID Journal Published Year Pages File Type
1403374 Journal of Molecular Structure 2013 5 Pages PDF
Abstract

The pKa values of isomeric sulfamoylquinolines 2a–8a and N,N-dimethylsulfamoylquinolines 2b–8b were determined by means of a UV–VIS spectroscopic method that uses absorbance diagrams, at constant ionic strength (0.15 M). For sulfamoylquinolines 2a–8a two pKa values – for basic function (Nring: −0.31 to 3.36) and for acid function (SO2NH2 group: 8.89–10.34) but only one in the case of N,N-dimethylsulfamoylquinolines 2b–8b (−0.05 to 3.07) – were obtained. The full geometry optimization in the 6–311 + G(d) basis set and the NBO population analysis were performed. Correlation between the experimentally determined and theoretically calculated (Sparc program) of pKa values as well as the differences between the calculated NBO population values for neutral and ionic forms were found for compounds 2a–7a and 2b–8b.

► pKa values of isomeric sulfamoylquinolines as pyridine-type bases were measured. ► pKa values of isomeric sulfamoylquinolines as SO2NH2 acids were determined. ► pKa values of N,N-dimethylsulfamoylquinolines as pyridine-type bases were measured. ► Correlations between pKa data and calculated NBO population values were found. ► pKa values were determined by means of a UV–VIS spectroscopic method.

Related Topics
Physical Sciences and Engineering Chemistry Organic Chemistry
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