Sulfuric Acid → HCID 18415047, compound

Participants

Reaction Conditions

Reaction Steps

A solution of concentrated sulfuric acid (4.0 mL, 75 mmol, 15 equiv) in dry methanol (50 mL) at 23° C. was added to a solution of 4,7-bis [[2-(trimethylsilyl)ethoxyl]methoxy]phthalide (60, 2.148 g, 5.034 mmol, 1 equiv) in dry methanol (50 mL) at 23° C. The reaction mixture was stirred for 2.0 h at 23° C. The product solution was partitioned carefully between saturated aqueous sodium bicarbonate solution (200 mL), saturated aqueous sodium chloride solution (150 mL), and ethyl acetate (100 mL). The aqueous layer was separated and extracted further with ethyl acetate (2×100 mL). The combined organic layers were dried over sodium sulfate and were concentrated affording the 4,7-dihydroxyphthalide (57) as an off-white solid (821 mg, 98%), which was used without further purification.

Provenance & Evidence