Sodium Azide → 3-Azido-L-alanine

Participants

Reaction Steps

A solution of (S)-3-amino-2-oxetanone p-toluenesulfonic acid salt (53.0 mg, 0.204 mmol) in DMF (1 mL) was added to NaN3 (14.6 mg, 0.225 mmol) in DMF (5 mL) and the mixture was stirred 3.5 h. The solvent was removed in vacuo at 25° C. The residue was dissolved in H2O (0.3 mL) and applied to a column of Bio-Rad Ion Retardation Resin Ag11 A8 (trademark) (15 g, 1×20 cm) and eluted with H2O (0.3 mL/min). Fractions containing amino acid were pooled and lyophilized to yield 25.6 mg (96%) of pure β-azido-L-alanine. For the optimum melting point this material was recrystallized by dissolving in a minimal volume of H2O at 40° C., adding MeOH (3 vol.) and acetone (until cloudy) and cooling to -20° C.: mp 174°-175° C. (dec); [α]D 25 +37.2 (± 0.5) (c 0.5, H2O); IR (K8r disk) 3420 (m, br), 3070 (s, br), 2113 (s), 1600 (vs, br), 1440 (s) cm-1 ; 1H NMR (300 MHz, d4 -MeOD)δ 3.63 (dd, 1H, 4.5, 12 Hz, CHHN3), 3.53 (dd, 1H, 7.2, 12 Hz, CHN3), 3.37 (dd, 1H, 4.5, 7.2 Hz, CH); 1H NMR (300 MHz, D2O)δ 3.93 (dd, 1H, 5.0, 17.5 Hz, CHHN3), 3.92 (m, 1H, CH), 3.84 (dd, 1H, 7.0, 17.5 Hz, CHHN3); EI-MS: 131.0570 (MH+, Calc. 131.0570 for C3H7N4O2), 88.0400 (MH+ -HN3), 85.0515 (M-CO2H), 74.0245 (Base peak, M-CH2N3); POSFAB-MS (glycerol) 131 (MH+); Rf 0.80 (System A; UV active; brown-purple with ninhydrin).

Provenance & Evidence