Print version Print setup

Reduction of phenylglycine; amino alcohol

SyntheticPage 275
DOI: 10.1039/SP275
Submitted Jun 03, 2008, published Jun 03, 2008
Suzanne Elizabeth Howson (s.e.howson@warwick.ac.uk)


			Reaction Scheme: Reduction of phenylglycine

Chemicals Used

NaBH4 (Fisher Scientific),
Iodine (Sigma Aldrich),
Phenylglycine (Sigma Aldrich),
KOH (Fisher Scientific),
THF (distilled over potassium).

Procedure

Sodium borohydride (31.21 g, 0.825 mol) in a dry three-necked round-bottom flask was put under Argon and dry THF (400 ml) was added. The solution was stirred whilst phenylglycine (50.00 g, 0.33 mol) was added as a solid in one portion. The flask was cooled to 0oC using an ice-water bath and fitted with a reflux condenser. Iodine (83.75 g, 0.33 mol) in dry THF (100 ml) was added dropwise to the solution. The reaction was then stirred at ambient temperature for 2 h, before heating to reflux (80oC) overnight. Methanol (~400 ml) was added slowly until the solution became clear. All solvent was then removed on the rotary evaporator to leave a white paste, which was then dissolved in aqueous 20% potassium hydroxide solution (600 ml) and stirred at ambient temperature overnight. The product was extracted into dichloromethane (5 x 250 ml), dried over sodium sulphate and the solvent removed to leave the crude product (crude yield = 48.00 g). The product was recrystallised from hot toluene. Yield = 23.33 g, 0.17 mol, 52%.

Author's Comments

Adapted from prep for (S)-tert-Leucinol.

Data

1H NMR (400 MHz, 298 K, CDCl3) 7.30-7.18 (5H, m, Ph), 3.97 (1H, dd, 3JHH = 4 Hz, 8 Hz), 3.66 (1H, dd, 2JHH = 11 Hz, 3JHH = 4 Hz, CH2), 3.48 (1H, dd, 2JHH = 11 Hz , 3JHH = 8 Hz, CH2), 2.05 (2H, s, NH2).

Lead Reference

Evans, Peterson, Johnson, Barnes, Campos and Woerpel, J. Org. Chem., 1998, 63, 4541.

Supplementary Information

1H NMR (seh.jcamp)

This page has been viewed approximately 30230 times since records began.

Get structure file (.cdx, .sk2, .mol)

Keywords: alcohol, amino acid, Phenylglyicol, Reduction, Sodium Borohydride

Loading ...