L. Elrod, S. Spanton, M. Cirovic
Aug 2, 1993
Citations
0
Influential Citations
1
Citations
Journal
Analytica Chimica Acta
Abstract
Abstract 2-Chloro-4,5-difluorobenzoic acid (CDFBA) and related impurities are determined using liquid chromatography (LC). Separations are achieved using a reversed-phase isocratic system with an ion-pair reagent (tetrabutylammonium hydroxide). Unique isomeric impurities observed in commercially produced CDFBA were isolated and identified by NMR and single crystal x-ray diffraction. The method has relative standard deviations of ± 0.55% to ±1.26% for the CDFBA determination and from ±4.3% to ±12% for impurities below 0.3% in CDFBA. Impurities are determinable to at least 0.03% by weight.