반응 #474698

반응 방정식

DIBAL-H

tert-butyl 2,2-dimethyl-5-oxopyrrolidine-1-carboxylate

→

tert-butyl 5-methoxy-2,2-dimethylpyrrolidine-1-carboxylate

수율 96.9%

용매

Et2O

MeOH

반응 조건

후처리

1. 1
   온도to warm to room temperature
2. 2
   workup.STIRRINGstirred overnight
3. 3
   기타The reaction was quenched with NH4OH (50 mL)
4. 4
   workup.STIRRINGstirred for 20 minutes
5. 5
   workup.ADDITIONThe reaction was then diluted with EtOAc (200 mL), 0.5M Rochelle's Salt (100 mL)
6. 6
   workup.ADDITIONwas added
7. 7
   기타the layers were separated
8. 8
   세척The organic fraction was washed with 0.5M Rochelle's Salt (2×100 mL), brine (100 mL)
9. 9
   건조dried (MgSO4)
10. 10
    농축concentrated to an oil
11. 11
    workup.STIRRINGstirred overnight at room temperature
12. 12
    농축The reaction was then concentrated
13. 13
    세척washed with saturated Na2CO3 (2×100 mL), brine (50 mL)
14. 14
    건조dried (MgSO4)
15. 15
    농축concentrated

실험 절차

DIBAL-H (73.65 mL, 110.5 mmol, 1.5M in toluene) was added portionwise to a solution of tert-butyl 2,2-dimethyl-5-oxopyrrolidine-1-carboxylate (23.10 g, 108.3 mmol) in dry Et2O (200 mL) cooled to −78° C. The reaction was stirred for 1 hour at −78° C. and then allowed to warm to room temperature and stirred overnight. The reaction was quenched with NH4OH (50 mL) and stirred for 20 minutes. The reaction was then diluted with EtOAc (200 mL), 0.5M Rochelle's Salt (100 mL) was added, and the layers were separated. The organic fraction was washed with 0.5M Rochelle's Salt (2×100 mL), brine (100 mL), dried (MgSO4) and concentrated to an oil. The oil was taken up in a solution of p-TsOH monohydrate (2.06 g, 10.8 mmol) in MeOH (200 mL) and stirred overnight at room temperature. The reaction was then concentrated, taken up in EtOAc (200 mL), washed with saturated Na2CO3 (2×100 mL), brine (50 mL), dried (MgSO4) and concentrated to give tert-butyl 5-methoxy-2,2-dimethylpyrrolidine-1-carboxylate (24.07 g, 96.9% yield) as an oil.

출처