Synthesis
The general procedure for the synthesis of 4''-amino-3''-bromoacetophenone from 4-aminoacetophenone was as follows: 1-(4-aminophenyl)ethanone (10.0 g, 74.0 mmol) was dissolved in acetonitrile (50 mL), and an acetonitrile solution of N-bromosuccinimide (13.8 g, 77.7 mmol) was slowly added dropwise (30 mL) under ice-bath cooling conditions. After the dropwise addition, the reaction mixture was stirred at room temperature for 20 hours. After completion of the reaction, the solvent was removed by distillation under reduced pressure and the residue obtained was dissolved in ethyl acetate. The organic layer was washed sequentially with saturated aqueous sodium bicarbonate and saturated saline and dried with anhydrous sodium sulfate. Finally, the solvent was evaporated under reduced pressure to afford the target product 4''-amino-3''-bromoacetophenone as a yellow powder (15.8 g, 100% yield). The structure of the product was confirmed by 1H-NMR (CDCl3, 400 MHz): δ 2.49 (3H, s), 4.52-4.70 (2H, br), 6.73 (1H, d, J = 8.5 Hz), 7.73 (1H, dd, J = 8.5, 1.9 Hz), 8.05 (1H, d, J = 1.9 Hz).
References
[1] Patent: US2016/207883, 2016, A1. Location in patent: Paragraph 0644-0646
[2] Synthetic Communications, 2009, vol. 39, # 2, p. 215 - 219
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[4] Journal of Labelled Compounds and Radiopharmaceuticals, 2016, vol. 59, # 13, p. 552 - 556
[5] Agricultural and Biological Chemistry, 1984, vol. 48, # 11, p. 2883 - 2888
