Ammonium Chloride → 2-Propyloxybenzamidine Hydrochloride

Temperature

2.5 °C

21.41 g (400 ml) of ammonium chloride are suspended in 400 ml of toluene and cooled to from 0 to 5° C. 200 ml of a 2M solution of triethylaluminium in hexane are added dropwise, and the mixture is stirred at room temperature until evolution of gas has ceased. 32.2 g (200 mmol) of 2-propoxybenzonitrile are added, and the reaction mixture is then stirred at 80° C. (bath) overnight. The cooled reaction mixture is, with ice-cooling, added to a suspension of 300 g of silica gel and 2.85 ml of ice-cold chloroform and stirred for 30 minutes. The mixture is filtered off with suction and the filter residue is washed with the same amount of methanol. The solvent is distilled off under reduced pressure, the residue is stirred with 500 ml of a mixture of dichloromethane and methanol (9:1), the solid is filtered off and the mother liquor is evaporated. The residue is stirred with petroleum ether and filtered off with suction. This gives 22.3 g (52%) of product.

1. stirringthe reaction mixture is then stirred at 80° C. (bath) overnight
2. customThe cooled reaction mixture
3. temperaturecooling
4. stirringstirred for 30 minutes
5. filtrationThe mixture is filtered off with suction
6. washthe filter residue is washed with the same amount of methanol
7. distillationThe solvent is distilled off under reduced pressure
8. stirringthe residue is stirred with 500 ml of a mixture of dichloromethane and methanol (9:1)
9. filtrationthe solid is filtered off
10. customthe mother liquor is evaporated
11. stirringThe residue is stirred with petroleum ether
12. filtrationfiltered off with suction

ORD record

ord-5c8caa0a90e64b04b5908a00e815bd8d

Source dataset

uspto-grants-2005_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06943163B2