(CAS NO.: ), which is also known as , 9,10-dibromo-, could be produced through the following synthetic routes.

To a suspension of 300 g. (1.35–1.43 moles) of anthracene of 80–85 per cent purity in 3 l. of carbon tetrachloride, in a 5-l. flask fitted with dropping funnel, stirrer, and reflux condenser, is added slowly 567 g. (182 cc., 3.55 moles) of bromine. The bromination takes place in the cold with separation of the sparingly soluble 9,10-dibromoanthracene; in order to prevent undissolved anthracene from becoming coated over, it is necessary to maintain vigorous stirring throughout the reaction. A tube from the top of the condenser conducts hydrogen bromide to cold water, in which it is absorbed. The addition of the bromine occupies about one-half hour; the rate is so adjusted that a minimum of bromine is carried over with the hydrogen bromide.

When all the bromine has been added, the mixture is gently warmed on a steam bath with continual stirring, care being taken not to so rapidly as to cause undue loss of bromine by entrainment. Heating is continued until the mixture has boiled gently for one hour. The mixture is then allowed to cool for some hours, without stirring, and the crude dibromoanthracene is filtered off, washed with a little cold carbon tetrachloride, and dried. In this way 270-425 g. of a bright yellow product, which melts at 218–219° (corr.), is obtained. On concentrating the mother liquors, 15–150 g. more of crude material, m.p. about 216° (corr.), can be obtained.

To prepare a purer product, the crude dibromoanthracene is extracted with carbon tetrachloride in an apparatus similar to that described on p. 375, the extraction is carried to the point at which crystals just begin to separate from the boiling solvent, and a fresh quantity of carbon tetrachloride is then taken. About eight extractions are necessary, 1 l. being used each time. The 9,10-dibromoanthracene so purified consists of brilliant yellow needles melting at 221–222° (corr.). A further quantity of pure product may be obtained by concentrating the mother liquor and recrystallizing the second crop so obtained. The recovered solvent may be employed for further extractions. The yield amounts to 400–420 g. (83–88 per cent of the theoretical quantity based on anthracene of 85 per cent purity).