Hydrochloric Acid → 3,3-Dimethyl-2,3-dihydro-1-benzofuran-5-ol

Participants

Reaction Conditions

Reaction Steps

To a solution of [3-bromo-4-(2-methylallyloxy)phenyl]acetate (Intermediate 43, 190 mg, 0.67 mmol) in toluene (5 mL) azobisisobutyronitrile (0.13 g, 0.80 mmol) and tributylstannane (0.39 g, 1.33 mmol) were added and the reaction mixture was stirred for 2 hours at 90° C. Methanol (5 mL), water (3 mL) and sodium hydroxide 2M solution in water (0.67 ml, 1.33 mmol) were added and the reaction mixture was stirred for 1 hour at room temperature. A 2N aqueous solution of HCl was added while the pH was allowed to reach ˜3-4 and ethyl acetate (30 ml) was added. Two phases were separated and a 10% w/w solution of KF was added to the organic phase and the mixture was stirred for 1 hour at room temperature. The solid was filtered off and the solution was dried (Na2SO4), and evaporated. The residue was purified by flash chromatography (Biotage system) on silica gel using a SNAP 25 g as column and cyclohexane/ethyl acetate from 100:0 to 70:30 as eluent affording the title compound (95 mg) as white solid.

Provenance & Evidence