Hydrochloric Acid → (1R)-2-((2-(4-Nitrophenyl)ethyl)amino)-1-phenylethan-1-ol--hydrogen chloride (1/1)

Temperature

-18 °C

A mixture of 7.51 kg of (R)-2-hydroxy-N-[2-(4-nitrophenyl)ethyl]-2-phenylacetamide, 23 liters of 1,3-dimethyl-2-imidazolidinone and 23 liters of tetrahydrofuran was cooled at −18° C. and 49.4 kg of 1M boran-tetrahydrofuran solution was dropped there into at not higher than −7° C. After that, temperature of the mixture was raised to 70° C. followed by stirring for 5 hours. The reaction mixture was cooled at −12° C. and 2.9 kg of methanol and 5.9 kg of concentrated hydrochloric acid were added thereto at not higher than 5° C. After stirring at 68° C. for 1 hour, the mixture was concentrated in vacuo until the amount became 50 liters. A 30% aqueous solution (60 kg) of K2CO3 and 6 liters of water were added thereto followed by extracting with 75 liters of ethyl acetate. The organic layer was washed with 75 liters of water and concentrated in vacuo. Isopropanol (75 liters) was added to the residue, the mixture was dissolved at 40° C. and 2.46 kg of concentrated hydrochloric acid was added to crystallize followed by stirring at 23° C. throughout one night. The crystals were filtered and washed with 38 liters of isopropanol. They were dried in vacuo to give 7.29 kg of (R)-2-[[2-(4-nitrophenyl)ethyl]amino]-1-phenylethanol monohydrochloride.

1. temperatureAfter that, temperature of the mixture was raised to 70° C.
2. temperatureThe reaction mixture was cooled at −12° C.
3. customhigher than 5° C
4. stirringAfter stirring at 68° C. for 1 hour
5. concentrationthe mixture was concentrated in vacuo until the amount
6. additionA 30% aqueous solution (60 kg) of K2CO3 and 6 liters of water were added
7. extractionby extracting with 75 liters of ethyl acetate
8. washThe organic layer was washed with 75 liters of water
9. concentrationconcentrated in vacuo
10. additionIsopropanol (75 liters) was added to the residue
11. dissolutionthe mixture was dissolved at 40° C.
12. addition2.46 kg of concentrated hydrochloric acid was added
13. customto crystallize
14. stirringby stirring at 23° C. throughout one night
15. filtrationThe crystals were filtered
16. washwashed with 38 liters of isopropanol
17. customThey were dried in vacuo

ORD record

ord-aa38a797ab4d4f9884f32a9bc04be312

Source dataset

uspto-grants-2010_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07750029B2