[CH:1]([O:4][C:5]1[CH:12]=[CH:11][C:8](C=O)=[CH:7][CH:6]=1)([CH3:3])[CH3:2].[OH-:13].[K+].C(Br)(Br)Br.[OH-].[K+].CO.[O:23]1[CH2:28][CH2:27][O:26][CH2:25]C1>CO>[CH:1]([O:4][C:5]1[CH:12]=[CH:11][C:8]([CH:27]([O:26][CH3:25])[C:28]([OH:23])=[O:13])=[CH:7][CH:6]=1)([CH3:3])[CH3:2]An oven-dried flask was charged with 4-isopropoxybenzaldehyde (4.9 g, 29.9 mmol), anhydrous methanol (30 mL) and anhydrous dioxane (30 mL) then fitted with an addition funnel. The addition funnel was charged with a solution of KOH (8.4 g, 149.5 mmol) in anhydrous methanol (30 mL) and an aliquot (˜2 mL) was added to the reaction mixture. Bromoform (3.4 mL, 38.8 mmol) was added to the reaction mixture then the remaining KOH/MeOH solution was added dropwise over 10 minutes. After stirring for 18 hours, the mixture was concentrated in vacuo. The residue was diluted with water and the pH was adjusted to ˜2 using concentrated HCl then extracted with EtOAc. The combined organics were dried over Na2SO4 and filtered. Concentration of the filtrate in vacuo gave 2-(4-isopropoxyphenyl)-2-methoxyacetic acid as a light yellow solid (6.8 g) which was used without further purification.
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