Multi-wavelength spectrophotometric determination of acidity constant of some newly synthesized Schiff bases and their QSPR study

Hemmateenejad, B; Emami, L; Sharghi, H

HERO ID

1042407

Reference Type

Journal Article

Year

2010

Language

English

PMID

20004138

HERO ID 1042407
In Press No
Year 2010
Title Multi-wavelength spectrophotometric determination of acidity constant of some newly synthesized Schiff bases and their QSPR study
Authors Hemmateenejad, B; Emami, L; Sharghi, H
Journal Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
Volume 75
Issue 1
Page Numbers 340-346
Abstract The acidity constants of some newly synthesized Schiff base derivatives were determined by hard-model based multivariate data analysis of the spectrophotometric data in the course of pH-metric titration in 50% (v/v) methanol-water binary solvent. The employed data analysis method was also able to extract the pure spectra and pH-dependent concentration profiles of the acid-base species. The molecules that possess different substituents (both electron donating and withdrawing) on the ortho-, meta- and para-positions of one of the phenyl ring showed variable acidity constants ranging from 8.77 to 11.07 whereas the parent molecule had an acidity constant of 10.25. To investigate the quantitative effects of changing of substitution pattern on the acidity constant, a quantitative structure-property relation analysis was conducted using substituent constants and molecular descriptor. Some models with high statistical quality (measured by cross-validation Q(2)) were obtained. It was found that the acidity constant of the studied molecules in the methanol-water mixed solvent not only is affected by electronic features of the solutes but also by the lipophilic interaction between methanol part of solvent and the deprotonated solutes.
Doi 10.1016/j.saa.2009.10.037
Pmid 20004138
Wosid WOS:000274773700052
Is Certified Translation No
Dupe Override No
Comments Source: Web of Science 000274773700052
Is Public Yes
Language Text English
Keyword Schiff base; Acidity constant; Chemometrics; Methanol-water; Quantitative structure-property relationship
Is Qa No