Water → HCID 178421809, compound

Participants

Reaction Steps

3-Trifluoroethylamino-4-methylphenol (13.9 g; 0.068 mole) and phthalic anhydride (15.05 g; 0.102 mole - 1.5 mole equivalents) were heated in a 500 ml round-bottomed, single-neck flask equipped with a short, water-cooled reflux condenser in a 160° oil bath for three hours. A temperature in the range of 150°-180° C. is acceptable. At the start of the reaction the melt was swirled from time to time to facilitate mixing. A further batch of 3-trifluoroethylamino-4-methylphenol (14.0 g; 0.068 mole) was warmed with 85% phosphoric acid (25 ml plus 10 ml) and was transferred to the cooled reaction mixture. The flask was heated for four hours at an oil bath temperature of 170 ; again with occasional swirling. Methanol (170 ml; 25 ml per 0.01 M) was added to the cooled but still warm reactants and the mixture was refluxed for twenty minutes. Crystals appeared almost immediately and the liquid was stored in a 4° refrigerator overnight. Filtration, washing with cold methanol, and drying gave 25.1 g of red-orange crystals. A second crop 0.9 g (total yield 73%) came from the filtrate kept several days at 4° C.

Provenance & Evidence