Boron tribromide → 2-[4-(4-Hydroxy-3-isopropylbenzyl)-3,5-dimethylanilino]-2-oxoacetic acid
Reaction equation
[CH:1]([C:4]1[CH:5]=[C:6]([CH:24]=[CH:25][C:26]=1[O:27]C)[CH2:7][C:8]1[C:21]([CH3:22])=[CH:20][C:11]([NH:12][C:13](=[O:19])[C:14]([O:16]CC)=[O:15])=[CH:10][C:9]=1[CH3:23])([CH3:3])[CH3:2].B(Br)(Br)Br>ClCCl>[OH:27][C:26]1[CH:25]=[CH:24][C:6]([CH2:7][C:8]2[C:9]([CH3:23])=[CH:10][C:11]([NH:12][C:13](=[O:19])[C:14]([OH:16])=[O:15])=[CH:20][C:21]=2[CH3:22])=[CH:5][C:4]=1[CH:1]([CH3:3])[CH3:2]Participants
4
Procedure
128 mg (0.33 mmol) of ethyl 2-[4-(3-isopropyl-4-methoxybenzyl)-3,5-dimethyl-anilino]-2-oxoacetate (Example 1) in 5 ml of dichloromethane at −78° C. under argon are treated dropwise with 167 mg (0.66 mmol) of boron tribromide. The reaction mixture is stirred at room temperature for 2.5 hours. It is poured into buffer of pH 7, the phases are separated, the aqueous phase is acidified with buffer of pH 4 and, after extraction with dichloromethane, the organic phases are combined. The solution is dried over sodium sulphate and the solvent is removed in vacuo. 112 mg (98%) of 2-[4-(4-hydroxy-3-isopropylbenzyl)-3,5-dimethylanilino]-2-oxoacetic acid are obtained.