PROCESS FOR THE PREPARATION OF 2,3,4,5,-TETRAFLUOROBENZENE DERIVATES

摘要

2,3,4,5-tetrafluorobenzene derivatives can be obtained in a particularly advanta geous manner by reacting the corresponding chloro-benzene or (chloro, fluoro)-benzene derivatives with a fluoridating agent in the presence of a solvent and a catalys t at elevated temperature. which comprises carrying out the reaction initially under temperature and pressure conditions such that the respective 2,3.4,5-tetrafluoro -benzene derivative continuously distills off through a column, and subsequently setting temperature and pressure conditions such that residual fractions of the 2,3,4,5-tetrafluorobenzene derivative distill off with the corresponding 2.3,4-trifluoro -5-chloro compound.