Citric Acid → BOC-D-alanine

Participants

Reaction Steps

To a suspension of D-alanine (1 g, 11.22 mmol) in water (5.6 mL)/MeOH (2.80 mL) (2:1) K2CO3 (1.55 g, 11.22 mmol) was added at 0-5° C., followed by a solution of Boc2OO (2.61 mL, 11.22 mmol) in MeOH (2.80 mL) over 5 min. The resulting suspension was stirred for 23 h at rt. The reaction mixture was poured into water and acidified to pH=3 with aqueous citric acid solution. The white cloudy solution was extracted with DCM (3×). Organic layers were combined, washed with brine, dried over MgSO4, filtered and the solvent removed to yield 1.78 g, 9.43 mmol (R)-2-tert-butoxycarbonylamino-propionic acid.

Provenance & Evidence