Ammonia → 2,6-Dichlorobenzoxazole

Participants

Reaction Steps

109 g (1 mole) of 2-aminophenol and 63 g (1.05 mole) of urea are suspended in 350 ml of o-dichlorophenol and the suspension is heated to 150° to 160° C. under nitrogen for 3 hours, ammonia escaping. About 100 ml of the solvent are distilled off by a slight lowering of the pressure and subsequently 300 ml of fresh o-dichlobenzene are added. At an interior temperature of 110° C. 78 g (1.1 mole) of chlorine are then passed in within 1 to 2 hours, hydrogen chloride escaping. The raw mixture is reacted with phosphorus pentachloride and worked up analogously to Example 8. 115 g (61% of theory) of 2,6-dichlorobenzoxazole are obtained. GC purity: 96.8%.

Provenance & Evidence