The tert-butyl 1-(4-chlorophenyl)-2-hydroxyethylcarbamate used in the above reaction was prepared as follows. 2-Amino-2-(4-chlorophenyl)acetic acid (12 g, 64.65 mmol) was stirred in THF (200 mL) and sodium borohydride (5.82 g, 153.87 mmol) was added in portions to the stirred mixture under nitrogen. A solution of iodine (16.41 g, 64.65 mmol) in THF (20 mL) was added dropwise maintaining the temperature below 15° C. using an ice bath. The resulting mixture was warmed to room temperature and stirred at reflux overnight. The reaction was quenched by the addition of methanol (40 mL). A portion of this solution was removed (50 mL) and partitioned between ethyl acetate and water. The organic layer was concentrated under reduced pressure. The residue was purified by MPLC on silica using gradient elution (0 to 10% methanol/DCM). The desired product, 2-amino-2-(4-chlorophenyl)ethanol (1.318 g, 11.88%), was thus isolated as a colourless solid.
