Synthesis of Bromochloropolyfluorobiphenyls Containing Bromine and Chlorine Atoms in the 4 and 4,4′ Positions

A new method for the synthesis of 4-chlorononafluoro- and 4-bromononafluorobiphenyl by the reactions of nonafluorobiphenyl-4-thiol with Cl2, PCl5, and Br2, as well as of 4,4′-dichlorooctafluorobiphenyl from octafluorobiphenyl-4,4′-dithiol, 4′-chlorooctafluorobiphenyl-4-thiol, Cl2, and PCl5 was developed. 4-Bromo-4′-chlorooctafluorobiphenyl was synthesized for the first time from 4′-chlorooctafluorobiphenyl-4-thiol and Br2. 4,4′-Dichlorooctafluorobiphenyl was obtained as the main product in the reaction of 4′-bromooctafluorobiphenyl-4-thiol with PCl5.