Benzoyl chloride → HCID 12478920, compound

Participants

Reaction Steps

70.3 g of benzoyl chloride and 40 g of 50% strength aqueous sodium hydroxide solution are added simultaneously via 2 feed apparatuses in the course of 40 minutes at from 20° to 35° C. to a stirred mixture of 85.8 g of 6-chloroanthranilic acid, 1.3 g of tetrabutylammonium iodide, 0.5 g of dimethylformamide and 1,300 g of 1,2-dichlorobenzene. Stirring is continued for 90 minutes at 30° C., the water is separated off at from 75° to 90° C. and under from 20 to 50 mbar and 64 g of phosgene are added via a gas inlet tube in the course of 1 hour at from 100° to 105° C., while stirring. The mixture is cooled to room temperature while nitrogen is passed through, after which insoluble substances are filtered off and the filtrate is evaporated down, in the final stage at 140° C. and under 20 mbar. Distillation at 221°-230° C. and under 4-5 mbar gives 121 g (94%) of 5-chloro-2-phenyl-4H-3,1-benzoxazin-4-one of melting point 155°-157° C. The product is 99.5% pure according to HPLC.

Provenance & Evidence