4-BROMO-2-FLUORO-5-METHYLBENZALDEHYDE

Conditions: temp:22.01; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: NaH2PO4 (418 mg, 3.48 mmol) in H2O (17.6 ml), a 35% aqueous H2O2 solution (2.5 ml, 25.7 mmol) and NaClO2 (2.23 g, 24.7 mmol) in H2O (34.9 ml) were sequentially added to a mixture of 4-bromo-2-fluoro-5-methyl-benzaldehyde (3.74 g, 17.2 mmol) in MeCN (52 ml) at 0° C. The mixture was stirred at room temperature for 14 hours, and then made acidic (pH 3) with a 10% aqueous HCl solution and extracted with ethyl acetate (3×100 ml). The organic layers were washed with H2O (70 ml), and then dried over MgSO4 and concentrated under reduced pressure to give 4-bromo-2-fluoro-5-methyl-benzoic acid as a pale orange solid (4.02 g, 100%). extracted with ethyl acetate (3×100 ml) The organic layers were washed with H2O (70 ml) dried over MgSO4 concentrated under reduced pressure

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: n-BuLi (5.0 ml, 8.0 mmol, 1.6 M in hexane) was added dropwise to a solution of n-Bu2Mg (8.0 ml, 8.0 mmol, 1.0 M in heptane) at room temperature for 10 minutes. The mixture was stirred at room temperature for 15 minutes and then cooled to −10±2° C. A solution of 2,5-dibromo-4-fluorotoluene (5.466 g, 19.59 mmol) in toluene (30 ml)-THF (6 ml) was added dropwise to this mixed reaction solution over 30 minutes, and the mixture was then stirred at 0° C. for one hour. The reaction mixture was added dropwise to a solution cooled to −10° C. of DMF (2.1 ml, 27 mmol) in toluene (7.6 ml) over 15 minutes. Further, this mixture was stirred at −10 to −5° C. for 30 minutes, and then quenched with an aqueous citric acid solution (2.3 M, 16 ml, 37 mmol) and extracted with Et2O. The organic layer was washed with water, and then dried over MgSO4 and concentrated under reduced pressure to give 4-bromo-2-fluoro-5-methyl-benzaldehyde (3.74 g, 88%). cooled to −10±2° C the mixture was then stirred at 0° C. for one hour The reaction mixture was added dropwise to a solution Further, this mixture was stirred at −10 to −5° C. for 30 minutes extracted with Et2O The organic layer was washed with water dried over MgSO4 concentrated under reduced pressure