Ethyl (3R)-5-oxo4-(phenylmethyl)-3-morpholinecarboxylate → (R)-Ethyl 4-benzylmorpholine-3-carboxylate

Participants

Reaction Steps

The title Compound was prepared according to the procedure used by G. R. Brown, J. Chem. Soc. Perkin Trans 1, 1985, 2577, using ethyl (3R)-5-oxo-4-(phenylmethyl)-3-morpholinecarboxylate (D45, 3.64 g, 13.84 mmol) in dry THF (70 mL), cooled in an ice bath before adding borane-dimethylsulphide complex (1.84 mL, 10 M), slowly. The reaction mixture was allowed to warm up to room temperature overnight. Stirred for further six hours, added more borane-dimethylsulphide complex and stirred at R.T. over the weekend. Reaction quenched carefully with water, dropwise till the effervescence had finished. Solvent evaporated. Residue dissolved in water, basified to pH ˜10 using 2N NaOH solution before extracting with Et2O. Organic layer was then extracted with 2N HCl solution. Acid layer was then basified using 2N NaOH solution before extracting with Et2O×3. Combined extracts were dried (MgSO4). Filtered. Evaporated under reduced pressure to afford the title compound as a colorless oil in a 68% yield.

Provenance & Evidence