56077-28-2

Step 1. Cyclohexyl ketone (0.30 mL, 2.4 mmol) was dissolved in pre-cooled methanol (3.0 mL, 74 mmol) in an ice bath. Subsequently, bromine (0.38 g, 2.4 mmol) was added slowly and dropwise to this solution. The reaction mixture was stirred for 2 hr. then water (3.0 mL) was added and stirring was continued for 4 hr. Upon completion of the reaction, the reaction mixture was extracted with a solvent mixture of ethyl acetate: hexane (3:1). The organic layers were combined and washed sequentially with water, saturated potassium carbonate solution and brine, then dried with magnesium sulfate. After concentration under reduced pressure, 2-bromo-1-cyclohexylethanone was obtained as a clear oil (0.49 g, 100%). The product was confirmed by NMR hydrogen spectrum (300 MHz, CDCl3): δ 3.96 (s, 2H), 2.86-2.55 (m, 1H), 2.24-1.08 (m, 10H).

[1] Bioorganic and Medicinal Chemistry Letters, 2010, vol. 20, # 16, p. 4918 - 4921
[2] Patent: WO2014/143768, 2014, A1. Location in patent: Page/Page column 90
[3] Bioorganic and Medicinal Chemistry Letters, 2008, vol. 18, # 3, p. 1223 - 1228
[4] Bioorganic and Medicinal Chemistry Letters, 2012, vol. 22, # 7, p. 2522 - 2526
[5] European Journal of Organic Chemistry, 2012, # 35, p. 6976 - 6985