Carbon Dioxide → 5-Bromo-3-dibenzylamino-2-fluorobenzoic acid

Participants

Reaction Steps

Add dropwise a solution of dibenzyl-(5-bromo-2-fluorophenyl)-amine (4.00 g, 10.8 mmol) in THF (12 mL) to a solution of lithium diisopropylamide, freshly prepared by adding n-butyllithium (1.6 M in hexanes, 7.09 mL, 11.3 mmol) to diisopropylamine (1.74 mL, 12.4 mmol) in THF (25 mL) at −78° C. Stir the resulting yellow solution at −78 C. for 45 min. Pour into a dry ice slurry containing about 100 g in dry THF (40 mL). Stir the solution until it reaches room temperature. Concentrate the solution and dissolve the residue in 10% aqueous potassium hydroxide solution (40 mL) and extract with diethyl ether (70 mL). Acidify the aqueous layer to about pH=3 with concentrated HCl. Extract the aqueous layer with diethyl ether (2×200 mL). Combine the organic layers and wash with water (150 mL), dry (magnesium sulfate) and concentrate to give the title compound as a solid (1.81 g, 40%).

Provenance & Evidence