1,2-Ethanedithiol → Methyl 3-(3-hydroxyphenyl)-3-methylbutanoate

To a solution of methyl 3-(3-methoxyphenyl)-3-methylbutanoate 85.E (0.227 g, 1.02 mmol) in 1,2-dichloroethane (10 mL) was added 1,2-ethanedithiol (1.37 mL, 16.3 mmol) followed by aluminum chloride (1.09 g, 8.17 mmol) at 0° C. The reaction mixture was allowed to slowly warm to room temperature over four hours and was then quenched with saturated Rochelle's salt (potassium sodium tartrate) solution. The mixture was extracted (2×50 mL) with DCM. The combined organic layers were washed with water (1×40 mL) and brine (1×40 mL) and dried over magnesium sulfate. The filtrate was concentrated and the residue was purified by medium pressure chromatography (silica, 0 to 30% EtOAc:hexanes) to give methyl 3-(3-hydroxyphenyl)-3-methylbutanoate 85 (0.209 g, 98.3% yield). MS ESI (pos.) m/e: 226.0 (M+H2O)+.