Ammonium Chloride → HCID 15434546, compound

A mixture of 1.4 g (7.1 mmol) of 5,6-difluorobenzofuran-2-carboxamide and 1.62 g (8.5 mmol) of triethyloxonium tetrafluoroborate in 40 ml of anhydrous dichloromethane was stirred at room temperature over 64 hours. Subsequently, the mixture was poured into 70 ml of saturated sodium hydrogen carbonate solution, extracted twice with 100 ml of dichloro-methane each time and the combined organic phases were washed once with 70 ml of saturated sodium hydrogen carbonate solution, dried over magnesium sulfate and concentrated in a vacuum. The brown solid obtained was dissolved in 30 ml of anhydrous ethanol, treated with 2 g of ammonium chloride and heated under reflux for 22 hours. The mixture was diluted with 90 ml of ethyl acetate and extracted three times with 50 ml of water each time. Subsequently, the combined aqueous phases were made basic with 3N sodium hydroxide solution and the solid was filtered off and washed with water. After drying there was obtained 0.55 g (40%) of 5,6-difluorobenzofuran-2-carboxamidine as a white solid with m.p. 178°.

1. extractionextracted twice with 100 ml of dichloro-methane each time
2. washthe combined organic phases were washed once with 70 ml of saturated sodium hydrogen carbonate solution
3. dry with materialdried over magnesium sulfate
4. concentrationconcentrated in a vacuum
5. customThe brown solid obtained
6. temperatureheated
7. temperatureunder reflux for 22 hours
8. extractionextracted three times with 50 ml of water each time
9. filtrationthe solid was filtered off
10. washwashed with water
11. customAfter drying there

ORD record

ord-9870f8c057264c43a398d76a4b9090d1

Source dataset

uspto-grants-1999_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05955495