[Br:1][C:2]1[C:3]([CH3:12])=[C:4]([CH:9]=[CH:10][CH:11]=1)[C:5]([O:7][CH3:8])=[O:6].S(OOS([O-])(=O)=O)([O-])(=O)=[O:14].[K+].[K+]>FC(F)(F)C(O)=O.FC(F)(F)C(OC(=O)C(F)(F)F)=O.CC1C=CC(C(C)C)=CC=1.CC1C=CC(C(C)C)=CC=1.Cl[Ru]Cl.Cl[Ru]Cl>[Br:1][C:2]1[C:3]([CH3:12])=[C:4]([C:9]([OH:14])=[CH:10][CH:11]=1)[C:5]([O:7][CH3:8])=[O:6]A solution of methyl 3-bromo-2-methylbenzoate (Cpd FF, 2.40 g, 10.5 mmol) in trifluoroacetic acid (50 mL) and trifluoroacetic anhydride (20 mL) in a sealed tube was treated with potassium persulfate (3.12 g, 11.5 mmol) and dichloro(p-cymene)ruthenium(II) dimer (0.170 g, 0.278 mmol). The reaction mixture was heated at 85° C. overnight. The volatiles were removed under vacuum and the resulting residue was taken up in dichloromethane and water. The aqueous phase was brought to pH˜5 with K3PO4 (sat. aq.). The layers were separated and the organic layer purified by column chromatography (0-30% ethyl acetate/heptane) to give methyl 3-bromo-6-hydroxy-2-methylbenzoate (Cpd GG, 1.94 g, 75%) as a clear oil.
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