Sodium borohydride → 1-Benzyl-4-methylpyrrolidin-3-ol

HRID 846696Notes

Reaction equation

[CH2:1]([N:8]1[CH2:12][CH:11]([CH3:13])[C:10](=[O:14])[CH2:9]1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[BH4-].[Na+]>C(O)C>[CH2:1]([N:8]1[CH2:12][CH:11]([CH3:13])[CH:10]([OH:14])[CH2:9]1)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

Conditions

Temperature: 0 °C

Procedure

A 15.58 g (82.3 mmol) sample of the ketone from step d was reduced to the alcohol by dissolving it in 32 mL of ethanol and adding the solution dropwise to a stirred suspension of sodium borohydride (3.11 g, 82.3 mmol) in 32 mL of ethanol at 0° C. The suspension was then stirred for 30 min at 0° C. and for 4 hours at room temperature. The solvent was then removed and the residue suspended in water. The product was extracted with methylene chloride and dried over anhydrous sodium sulfate, and the solvent was removed by evaporation under vacuum. The crude product was purified in a kugelrohr apparatus (160°-180° C. @ 1.0 Torr) to yield 1-benzyl-4-methyl-3-pyrrolidinol, MS M/Z 192 (M+H); NMR (CDCl3) d 1.04 (d, 3H, J=7.5 Hz), 1.90 (dd, 1H, J=7.5 Hz, J=9.0 Hz), 2.14 (m, 1H), 2.55 (dd, 1H, J=6.0 Hz, J=10.5 Hz), 2.82 (dd, 1H, J=3.0 Hz, J=10.5 Hz), 3.13 (dd, 1H, J=3.0 Hz, J=3.0 Hz), 3.82 (m, 2H), 3.95 (m, 1H), 7.33 (m, 5H).

Workup

additionadding the solution
customThe solvent was then removed
extractionThe product was extracted with methylene chloride
dry with materialdried over anhydrous sodium sulfate
customthe solvent was removed by evaporation under vacuum
customThe crude product was purified in a kugelrohr apparatus (160°-180° C. @ 1.0 Torr)

Sources & evidence

ORD record: ord-dea24cc75284486b82b8dfcd210c9c85
Source dataset: uspto-grants-1992_08
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05137892

Reaction notes

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