326.4 g (2.04 moles) of bromine is added dropwise in 6 hours with vigorous stirring, within a temperature range of between 20° and 45° C., to a mixture of 257.2 g (2 moles) of 2-chlorophenol, 1.0 g of zinc chloride and 1.0 g of diphenyl sulfide. After adding 70 ml of bromine, the temperature rises to 35° C. To avoid crystallization, the reaction mixture is afterwardheated to 40° C., Afterward, 20 ml of bromine is added dropwise. The remaining bromine is finally added at 45° C. After the addition of bromine is complete, stirring is maintained for 30 minutes at 50° C., and subsequently, the reaction product is freed at 60° C. under reduced pressure from dissolved hydrogen bromide to leave 414.5 g (99.8% of theory) of chlorobromophenol(3-Bromo-2-chlorophenol).
