Acetic Acid → HCID 19858390, compound

Participants

Reaction Steps

A mixture of 4-nitro phthalic anhydride (3.57 g, 18.5 mmol) and freshly prepared 4-aminobenzocyclobutene 2.20 g (18.5 mmol) was heated to reflux in acetic acid (100 ml) and toluene (100 ml) under nitrogen. The water of condensation was removed continuously and azeotropically using a Dean-Stark trap. After about 17 hrs, the dark but homogeneous reaction mixture was allowed to cool to room temperature and poured into 600 ml water. The mixture was then extracted with ethyl acetate (100 ml, then 4 ×50 ml). The organic extract was washed with aq. NaHCO3 and then H2O, and finally dried over MgSO4. Immediately after the removal of hydrated MgSO4 by filtration, the filtrate was subjected to rotary evaporation to provide slightly tacky yellow-green crude product, which was redissolved in CH2Cl2. The resultant solution was filtered through a bed of silica gel (approximately 20 g) and washed with CH2Cl2 until the filtrate was colorless. The combined filtrate was again stripped on a rotary evaporator to afford yellow plates, which was collected on a fitted filter funnel, washed with petroleum ether and dried in oven under vacuum at 80° C. overnight. Yield 3.85 g (71%). Calc. for C16H10N2O4 :65.30% C; 3.42% H; 9.52% N. Found: 64.17% C; 3.29% H; 9.54% N. Mass Spectroscopy: M+ (294, 100%).

Provenance & Evidence