Investigations on intermediate acetal formation during polarographic estimation of certain benzaldehyde derivatives

Terephthalaldehydic acid methyl ester (TAE) and 4-carboxybenzaldehyde (CBA) which are identified as critical impurities in the manufacturing of dimethyl terephthalate (DMT) and purified terephthalic acid (PTA), respectively, are compounds under investigation. During their polarographic estimation, i...

Full description

Saved in:
Bibliographic Details
Published in:Analytica chimica acta 1995-05, Vol.307 (1), p.55-60
Main Authors: Koshy, V.J., Prasad, J.V., Kalpana, G., Satish, S.
Format: Article
Language:English
Subjects:
4-Carboxybenzaldehyde (CBA)
Chemistry
Electrochemistry
Exact sciences and technology
General and physical chemistry
Kinetics and mechanism of reactions
Nuclear magnetic resonance spectrometry
Polarography
Terephthalaldehydic acid methyl ester (TAE)
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Terephthalaldehydic acid methyl ester (TAE) and 4-carboxybenzaldehyde (CBA) which are identified as critical impurities in the manufacturing of dimethyl terephthalate (DMT) and purified terephthalic acid (PTA), respectively, are compounds under investigation. During their polarographic estimation, it is seen that TAE had good stability in alkaline water-methanol whereas CBA was converted to an electroinactive species. Nuclear magnetic resonance, infrared, ultraviolet and mass spectrometric techniques were employed to identify the electroinactive product as an acetal. Neutralization of the acidic group in CBA is seen to prevent acetal formation. A method has been developed for the quantification of TAE and CBA incorporating a preconcentration step, and applied to their analysis in DMT and PTA.
ISSN:0003-2670
1873-4324
DOI:10.1016/0003-2670(95)00032-U