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

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 0^oC 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 (80^oC) 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%.

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

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

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