(5-bromo-2-chlorophenyl)(4-ethoxyphenyl)methanone

21900-52-7

103-73-1

461432-22-4

Under the protection of nitrogen, 2.1 g of tert-butyldimethylchlorosilane prepared in step 1) was mixed with 5-bromo-2-chlorobenzoyl chloride in anhydrous dichloromethane and stirred for 30 min at 0 to 10 °C. Subsequently, 1.2 mol of phenethyl ether and 1.1 mol of ferric chloride were sequentially added to the reaction system, and the reaction temperature was maintained at 14.7 °C, and the reaction continued to be stirred for 5 hours. After completion of the reaction, the reaction mixture was quenched by pouring it into ice water, extracted with dichloromethane, the organic phase was washed with water, and 31 g of 5-bromo-2-chloro-4'-ethoxy benzophenone (intermediate of dagliflozin) was obtained after concentration in 91.4% yield and 99.49% purity.