Hydrochloric Acid → 2,2-difluoro-5-isothiocyanatobenzo[d][1,3]dioxole

Participants

Reaction Steps

34.6 g of 5-amino-2,2-difluorobenzodioxole were added dropwise to a solution of 90 ml of conc. hydrochloric acid in 350 ml of water. The mixture was stirred for a further 30 minutes and then 27 g of thiophosgene were metered in rapidly. The mixture was stirred at the given temperature for a further 3 hours, the almost colourless suspension was admixed with 150 ml of dichloromethane and the dichloromethane was removed. The crude product was distilled at 45 mbar. 28 g (=89% of theory) were obtained as a colourless to yellowish liquid.

Provenance & Evidence