Pyridine → HCID 641323, compound

To a solution of 3-fluorophenol (22.4 g, 0.2 mol), pyridine (24 ml, 0.3 mol) and dichloromethane (200 ml) at room temperature was added 20 ml (0.225 mol) propionyl chloride over a period of 5 min. The reaction was exothermic. The solution was stirred for another 30 min. After addition of dichloromethane, the organic phase was washed with sat. NaHCO3 solution and water, dried over MgSO4 and concentrated in vacuo. 33.8 g (100%) of 3-fluoro-1-propionyloxybenzene was obtained. This compound was reacted with 33.3 g (0.25 mol) AlCl3 at 150° C. for a period of 10 min. After careful quenching with water, the reaction mixture was extracted three times with ether. The ether phase was dried (MgSO4) and evaporated to give 29.5 g (0.176 mol, 88%) rearranged product. This intermediate was dissolved in 200 ml of acetone and K2CO3 (42, 0.3 mol) and MeI (25 ml, 0.4 mol) were added. The reaction mixture was heated at 40° C. for a period of 12 h. The reaction mixture was filtered and the acetone was evaporated. The residue was dissolved in ether and the ether phase washed with a 0.5 M NaOH solution and water. Drying (MgSO4) and evaporation gave 31.2 g (0.17 mol, 86% yield for three steps) of 4-fluoro-2-methoxypropiophenone.

1. washthe organic phase was washed with sat. NaHCO3 solution and water
2. dry with materialdried over MgSO4
3. concentrationconcentrated in vacuo

ORD record

ord-d2b5a94be1b54042b8622cb217d49c78

Source dataset

uspto-grants-2006_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07148243B2