1,1'-Carbonyldiimidazole → 4-Methyl-3H-benzooxazol-2-one

Participants

Reaction Conditions

Reaction Steps

25.0 g (200 mmol) 2-amino-m-cresol and 70.4 ml. (400 mmol) DIPEA were placed in 1.0 L DCM and cooled to 0° C. A solution of 38.0 g (227 mmol) 1.1′-carbonyldiimidazole was added dropwise thereto over 30 min. The mixture was stirred for 30 min at 0° C., then overnight at RT. After evaporation of the reaction mixture i.vac. down to half its volume the aqueous phase was washed with water (2×250 mL), 1M aqueous potassium hydrogen sulphate solution (1×250 mL) and again water (1×250 mL). The organic phase was evaporated down i.vac. The crude product remaining as a solid was triturated with a mixture of diethyl ether and PE, the precipitated solid was suction filtered, washed with PE and dried i. vac.

Provenance & Evidence