Development of a Monitoring Method for Oxidative Coupling Reaction of 2-Naphthol in Solid State

Abstract

A monitoring method has been developed for 2-naphthol to 1,1’-bi-2-naphthol conversion reaction. The simultaneous monitoring procedure is based on zero-crossing first derivative spectrophotometry in basic aqueous media. Calibration graphs were obtained for the simultaneous determination. Zero-crossing first derivative wavelengths were 359.7-345.3 nm, respectively for 2-naphthol and 1,1'-bi-2-naphthol determinations. The method showed ability to determine 2-naphthol to 1,1'-bi-2-naphthol ratio 1:15-10:1 (w/w), accurately. Accuracy and reproducibility of the determination method on the known various mixtures of 2-naphthol and 1,1'-bi-2- naphthol were tested in their binary mixtures. The quantitative results of high performance liquid chromatography and analysis of synthetic mixtures (that were prepared according to the compositions obtained by the proposed method) showed satisfactory compatibility with the results of the proposed derivative method.