Benzene, 1-chloro-4-fluoro- → HCID 18445904, compound

Participants

Reaction Steps

The title compound was also prepared as follows. To a 100 L flask was charged sequentially 113.3 g (0.50 mol) of Pd(OAc)2, 331.4 g (1.11 mol) of 2-(di-t-butylphosphino)biphenyl, 2.476 kg (25.24 mol) of 1,3-cyclopentanedione, and 10.72 kg (50.5 mol) of powdered K3PO4. The resulting mixture was degassed (3×) by vacuum/N2 back fills. The vessel was then charged with 26 L of 1,4-dioxane and 4.28 kg (32.78 mol) of 1-chloro-4-fluorbenzene and the vessel degassed (3×) with vacuum/N2 back fills. The resulting slurry was heated to reflux for 12 h, cooled to rt, and water (23 L) was added. The vessel was rinsed with an additional 6 L of water and the reaction mixture further diluted with an additional 46 L of water. To the homogeneous solution was added 9 L of conc. HCl to adjust the pH to 1 and the solution aged for 2.5 h. The slurry was then filtered and the cake washed with 17 L of water and 17 L of toluene. The solid was then dried at 60° C. for 48 h, providing 2-(4-fluoro -phenyl)-1,3-cyclopentanedione as a light tan solid.

Provenance & Evidence