Acetic Anhydride → 2-Acetyl-1H-indene-1,3(2H)-dione

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-dimethylaminopyridine (664 mg, 5.44 mmol), triethylamine (7.6 ml 54.56 mmol), acetic anhydride (6.2 ml, 65.48 mmol in dry 1,2-dichloroethane (60,ml) was stirred at −20° C. and a solution of 1,3-indanedione (7.96 g, 54.56 mmol) in 1,2-dichloroethane was added dropwise in 1.5 h. The reaction mixture was stirred for 30 min, then washed with 10% hydrochloric acid (80 ml) and twice with water (80 ml). The organic phase was dried over MgSO4 and evaporated. The residue was crystallized from methyl-tert-butylether (50 ml) to give 2-acetyl-1,3-indanedione 38(6.5 g 63%). Rf 0.27 (hexane-ethylacetate-acetic acid 20-5-0.5) MS C11H8O3 m/z (%) 189 [M+H]+ (100), 166 (72), 104 (20).

Provenance & Evidence