2-Bromo-1-ethoxy-(2I',4'-dichloro)styrene and 2,2-dibromo-1-ethoxy-(2',4'-dichloro)styrene-the two impurities of bromfenvinphos; their identification, synthesis and full characterization

Abstract

Insecticide bromfenvinphos of 94-96% purity is manufactured in the Institute of Industrial Organic Chemistry. Besides the main component (bromfenvinphos), more than ten impurities are observed. Two new impurities: 2-bromo-1-ethoxy-(2',4'-dichloro)styrene (as a mixture of geometric isomers) and 2,2-di-bromo-1-ethoxy-(2',4'-dichloro)styrene were identified by means of mass spectrometry (MS) analysis. Both impurities were independently synthesized using 2,4-dichloroacetophenone as the starting material. The synthesized compounds were characterized spectroscopically and were found identical to the impurities which had been previously identified in bromfenvinphos. © Pesticide Science Society of Japan.