Determination of ethyl N-phenyl carbamate, 4,4′-methylenebis(ethyl phenylcarbamate) and 4,4′-methylenebis(phenyl isocyanate) by high-performance liquid chromatography

Abstract

A method for the determination of ethyl N-phenyl carbamate, 4,4′-, 2,4′- and 2,2′-methylenebis(ethyl phenylcarbamate) and methylenebis(phenyl isocyanate) was developed. The isocyanates were converted into urea derivatives by reaction with dibutylamine. The resulting compounds were determined by high-performance liquid chromatography on a bonded octadecylsilyl phase using isocratic elution with acetonitrile-water (75 + 25 v/v) or methanol–water (80 + 20 v/v) and ultraviolet detection at 254 nm.