Water → (Chlorothio)formyl chloride

Chlorocarbonylsulfenyl chloride was prepared by a literature procedure. A mixture of 784.9 g (4.22 mol) of trichloromethanesulfenyl chloride and 76 g (4.22 mol) of water dissolved in 886 ml of concentrated H2SO4 was stirred at 45°-50° for 1 hour in a 51. flask, at which time the initially-copious HC1 evolution had ceased. (Foaming presented problems in the beginning.) The mixture was transferred to a separatory funnel, and after 15 minutes, the layers were separated. The top, fluid layer, which amounted to 404.3 g (3.08 mol, 73% yield) of fairly pure chlorocarbonylsulfenyl chloride, was added to 373 g (3.08 mol) of benzamide in 1 1. of toluene in a 5 1. flask fitted with stirrer and reflux condenser. The mixture was stirred vigorously and was heated gently to 58°. A mildly exothermic reaction carried the temperature to 65° with foaming and vigorous gas evolution. The mixture was heated at 65° for 20 minutes, at 70° for 8 hours, at 70°-110° for 0.5 hours, and at 110° for 0.75 hours, at which time gas evolution had ceased. The reaction mixture was concentrated under vacuum to 1.5 mm and 90°. The residue was heated with 650 ml of methylcyclohexane; the mixture was treated with charcoal, filtered, and allowed to cool. The resultant solid was recrystallized from 650 ml of methylcyclohexane, heated to 75 (charcoal treatment and filtration) to give 375 g of very pale yellow solid, 5-phenyl-1,3,4 -oxathiazol-2-one, m.p. 64°-67°. An additional 27.2 g of product, m.p. 64°-67°, was obtained from the filtrates. The total yield, 412.2 g, corresponds to 75% of the theoretical amount.

1. customflask, at which time the initially-copious HC1 evolution had ceased
2. custom) The mixture was transferred to a separatory funnel
3. waitafter 15 minutes
4. customthe layers were separated
5. customflask fitted with stirrer
6. temperaturereflux condenser
7. stirringThe mixture was stirred vigorously
8. temperaturewas heated gently to 58°
9. customA mildly exothermic reaction
10. customto 65°
11. temperatureThe mixture was heated at 65° for 20 minutes, at 70° for 8 hours, at 70°-110° for 0.5 hours
12. waitat 110° for 0.75 hours
13. concentrationThe reaction mixture was concentrated under vacuum to 1.5 mm and 90°
14. temperatureThe residue was heated with 650 ml of methylcyclohexane
15. additionthe mixture was treated with charcoal
16. filtrationfiltered
17. temperatureto cool
18. customThe resultant solid was recrystallized from 650 ml of methylcyclohexane
19. temperatureheated to 75 (charcoal treatment and filtration)

ORD record

ord-fbecb717ee4842b4be446114741916c0

Source dataset

uspto-grants-1979_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04144047