Benzoyl chloride → HCID 12478920, compound

Participants

Reaction Conditions

Reaction Steps

92.3 g of benzoyl chloride and 52.6 g of 50% strength aqueous sodium hydroxide solution are introduced simultaneously via 2 feed apparatuses in the course of 40 minutes at from 22° to 38° C. to a stirred suspension of 128.6 g of 6-chloroanthranilic acid and 1.35 g of trimethylbenzylammonium chloride in 1,870 g of 1,2-dichloroethane. Stirring is continued for 30 minutes at 32° C., after which a further 16.3 g of benzoyl chloride and 9.3 g of 50% strength sodium hydroxide solution, as described above, are added in the course of 5 minutes, and the mixture is stirred for a further 55 minutes at from 25° to 30° C. The mixture is then refluxed for 11/4 hours to separate off water, this procedure being continued until the organic phase in the water separator no longer appears cloudy. 0.2 g of dimethylformamide are added, after which 96 g of gaseous phosgene are passed into the stirred refluxed mixture in the course of 13/4 hours, and excess phosgene is then expelled in the course of 5 minutes by blowing in nitrogen. After cooling to 40° C., the reaction mixture is extracted 3 times with water and once with a little concentrated sodium chloride solution. The organic phase is evaporated down under reduced pressure, in the final stage at 140° C. and under 20 mbar, 190.5 g (98.6%) of 5-chloro-2-phenyl-4H-3,1-benzoxazin-4-one of melting point 153°-156° C. being obtained. The purity according to HPLC is 97.4%.

Provenance & Evidence