156682-52-9

1,4-Dibromo-2,3-difluorobenzene is a halogenated benzene used in the preparation of various biologically active compounds such as non-nucleoside reverse transcriptase inhibitors. 1,4-Dibromo-2,3-diflu orobenzene is also used in the synthesis of conjugated polymers for organic photovoltaics.

1,4-Dibromo-2,3-difluorobenzene (5) was synthesized as follows: bromine (9.9 mL) was added to a 100 mL two-necked round-bottomed flask, which was connected to a condenser tube and a drying tube under ice bath conditions. Subsequently, 2,3-difluoro-1,4-bis(trimethylmethylsilyl)benzene (4.5 g, 19.34 mmol) was added, and the mixture was stirred at 58 °C for 1 hour. Next, another portion of bromine (0.5 mL) was added to the mixture and stirring was continued at the same temperature for 12 hours. Upon completion of the reaction, the mixture was cooled to 0 °C and the reaction was quenched by addition of sodium bicarbonate solution. The mixture was extracted with ethyl acetate and the organic phase was washed with brine and dried with magnesium sulfate. Subsequently, the solution was concentrated under vacuum using a rotary evaporator and the crude product was purified by column chromatography. The yield of the final product was 70%.

[1] Polymer, 2017, vol. 109, p. 115 - 125
[2] Journal of the American Chemical Society, 2015, vol. 137, # 32, p. 10420 - 10429
[3] Polymer, 2014, vol. 55, # 7, p. 1707 - 1715
[4] Patent: US2008/249151, 2008, A1. Location in patent: Page/Page column 16; 22-23
[5] Patent: US2006/25462, 2006, A1. Location in patent: Page/Page column 11; 20