tert-butyl 2-methyl-2-(phenylmethoxycarbonylamino)propanoate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of N-[(benzyloxy)carbonyl]-2-methylalanine (1 g, 4.21 mmol) in DCM (10 ml anhydrous), cyclohexane (10 ml) at 0° C. under nitrogen was added boron trifluoride diethyl etherate (7.7 μl, catalytic). tert-Butyl 2,2,2-trichloroacetimidate (1.51 ml, 8.43 mmol) in cyclohexane (10 ml) was then added slowly over 30 minutes before allowing to warm to RT. Reaction was allowed to stir at RT for 16 hours. To the crude reaction mixture was added 190 mg of NaHCO3 and the reaction filtered. The mother liquors were concentrated in vacuo. The crude extract was purified by column chromatography (10% EtOAc in heptane) to yield the desired product (0.863 g, 70% yield). Reaction To the crude reaction mixture the reaction filtered The mother liquors were concentrated in vacuo The crude extract was purified by column chromatography (10% EtOAc in heptane)