[NH2:1][C:2]1[CH:14]=[CH:13][C:5]([O:6][C:7]([CH3:12])([CH3:11])[C:8]([OH:10])=[O:9])=[CH:4][CH:3]=1.[OH-].[Na+].N(C1C=CC(O)=CC=1)[C:18]([CH3:20])=[O:19].CC(C)=O.C(Cl)(Cl)Cl>>[NH:1]([C:2]1[CH:3]=[CH:4][C:5]([O:6][C:7]([CH3:12])([CH3:11])[C:8]([OH:10])=[O:9])=[CH:13][CH:14]=1)[C:18]([CH3:20])=[O:19]FIG. 2A illustrates a reaction scheme for preparing 2-(4-aminophenoxy)-2-methyl propionic acid, a compound that is useful as a precursor in the preparation of Group I compounds. In accordance with the scheme of FIG. 2A, 8 grams (g) (0.2 mol) of pulverized sodium hydroxide is added to a suspension of 5.28 g (0.035 mol) of p-acetaminophenol in 23 g (0.4 mol) of acetone. The reaction mixture is stirred at room temperature for 1/2 hour. Subsequently, 3.58 g (0.03 mol) of chloroform is added dropwise over the course of 30 minutes. The reaction mixture is stirred overnight at room temperature and acetone is removed under vacuum. The residue is dissolved in water (10 ml), followed by acidification with 37% hydrochloric acid (HCl) to produce a pale yellow precipitate of 2-(4-acetaminophenoxy)-2-methyl propionic acid (5 g, 60% yield), crystallized from methanol, mp 69°-71° C.
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