반응 #474719

반응 방정식

DIBAL-H

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

→

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

수율 97.0%

용매

Et2O

MeOH

반응 조건

후처리

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

실험 절차

DIBAL-H (73.6 mL, 110.4 mmol) (1.5M in Toluene) was added portionwise to a solution of tert-butyl 2,2-dimethyl-5-oxopyrrolidine-1-carboxylate (23.1 g, 108.3 mmol) in dry Et2O (200 mL) cooled to −78° C. The reaction was stirred for 1 hour at −78° C., allowed to warm to room temperature and stirred for 15 hours. The reaction was quenched with NH4OH (50 mL), stirred for 20 minutes, and then diluted with EtOAc (200 mL) and 0.5M Rochelle's Salt (100 mL). The layers were separated. The organic fraction was washed with 0.5M Rochelle's (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 (2.0 g, 10.8 mmol) in MeOH (200 mL) and stirred for 15 hours at room temperature. The reaction was concentrated, taken up in EtOAc (200 mL), washed with saturated Na2CO3 (2×100 mL), brine (50 mL), dried (MgSO4) and concentrated to an oil, tert-butyl 5-methoxy-2,2-dimethylpyrrolidine-1-carboxylate (24.1 g, 97% yield).

출처