Reaktion #163205

Reaktionsgleichung

tetrahydrofuran

(R)-2-hydroxy-N-[2-(4-nitrophenyl)ethyl]-2-phenylacetamide

1,3-dimethyl-2-imidazolidinone

tetrahydrofuran

hydrochloric acid

→

(R)-2-[[2-(4-nitrophenyl)ethyl]amino]-1-phenylethanol monohydrochloride

Ausbeute 90.3%

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigehigher than −7° C
2. 2
   TemperaturAfter that, temperature of the mixture was raised to 70° C.
3. 3
   TemperaturThe reaction mixture was cooled at −12° C.
4. 4
   Sonstigehigher than 5° C
5. 5
   workup.STIRRINGAfter stirring at 68° C. for 1 hour
6. 6
   Einengenthe mixture was concentrated in vacuo until the amount
7. 7
   workup.ADDITIONA 30% aqueous solution (60 kg) of K2CO3 and 6 liters of water were added
8. 8
   Extraktionby extracting with 75 liters of ethyl acetate
9. 9
   WaschenThe organic layer was washed with 75 liters of water
10. 10
    Einengenconcentrated in vacuo
11. 11
    workup.ADDITIONIsopropanol (75 liters) was added to the residue
12. 12
    workup.DISSOLUTIONthe mixture was dissolved at 40° C.
13. 13
    workup.ADDITION2.46 kg of concentrated hydrochloric acid was added
14. 14
    Sonstigeto crystallize
15. 15
    workup.STIRRINGby stirring at 23° C. throughout one night
16. 16
    FiltrationThe crystals were filtered
17. 17
    Waschenwashed with 38 liters of isopropanol
18. 18
    SonstigeThey were dried in vacuo

Vorschrift

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 1 M boran-tetrahydrofuran solution was dropped thereinto 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.

Quelle