Hydrochloric Acid → HCID 178507235, compound

Participants

Reaction Steps

6.0 g (0.02 mol) of 4-chloro-3-(2,2-difluoro-5-nitrobenzo-1,3-dioxol-4-yl)pyrazole, in solution in 60 ml of ethanol, are run, at room temperature, onto a mixture of 30 ml of 36% HCl and 20.2 g (0.09 mol) of SnCl2 2H2O in 60 ml of ethanol. The reaction mixture is stirred for 2 h at room temperature, neutralised with 10% NaOH and then filtered. The insoluble material is washed with ethanol. The alcohol phase is concentrated under reduced pressure and the residue is taken up in ethyl acetate. After drying the organic phase and concentration under vacuum, the residue is triturated with 50 ml of heptane, filtered and dried. We obtain 4.6 g of 4-chloro,3-(5-amino,2,2-difluorobenzo-1,3-dioxol-4-yl)pyrazole melting at 195° C. (yield 84%).

Provenance & Evidence