Ammonium Hydroxide → 2-Chloro-3,4-dimethoxyphenethylamine

Temperature

0 °C

28.8 g of LiAlH4 was dispersed in 920 ml of THF in a nitrogen stream. A solution of 100 g of AlCl3 in 1220 ml of THF was added dropwise to the dispersion under cooling at 0° C. After the completion of the addition, the mixture was stirred for 1 hour and a solution of 92 g of 2-chloro-3,4-dimethoxy-β-nitrostyrene obtained in Step 3 in 1440 ml of THF was added dropwise thereto. After the mixture was stirred at room temperature overnight, 122 ml of water was carefully added dropwise thereto under cooling with ice and then 122 ml of concentrated NH4OH was added dropwise thereto. The mixture was stirred for 1 hour and crystals thus precipitated were separated by filtration and the mother liquor was concentrated under reduced pressure. 300 ml of ethyl acetate and a 10% NaOH aqueous solution were added to the residue to conduct extraction. After washing with water followed by dehydration over MgSO4 and concentration to dryness under reduced pressure, 2-(2-chloro-3,4-dimethoxyphenyl)ethylamine (63.9 g, 79%) was obtained.

1. additionAfter the completion of the addition
2. stirringAfter the mixture was stirred at room temperature overnight
3. temperatureunder cooling with ice
4. stirringThe mixture was stirred for 1 hour
5. customcrystals thus precipitated
6. customwere separated by filtration
7. concentrationthe mother liquor was concentrated under reduced pressure
8. addition300 ml of ethyl acetate and a 10% NaOH aqueous solution were added to the residue
9. extractionextraction
10. washAfter washing with water
11. concentrationfollowed by dehydration over MgSO4 and concentration to dryness under reduced pressure

ORD record

ord-af169859e73249d3aedaa9590b775f5f

Source dataset

uspto-grants-1994_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05292521