Potassium Phosphate, Dibasic → Phospho-L-serine

Participants

Reaction Steps

K2HPO4 (0.446 g, 3.28 mmol, dried 4 h at 130° C.) and 18-crown-6 ether (0.867 g, 3.28 mmol) were stirred 16 h in anhydrous DMF (10 mL). BOC-L-serine β-lactone (169 mg, 0.902 mmol) was deprotected to (S)-3-amino-2-oxetanone trifluoroacetic acid salt and added as a solution in DMF (3 mL). The mixture was stirred 3 days, diluted with H2O (to 50 mL), and applied to a column of AG1-X8 (trademark) (80 mL, 3 cm dia., OH- form). Elution (2 mL/min) with a linear gradient (0 to 3M over 10 L) of formic acid afforded O-phospho-L-serine 145.6 mg) in 87% yield after lyophilization: mp 170°-171° C. (dec) (lit. mp 175°-176° C. (dec)); [α]D 25 +7.2° (c 1.0, H2O) (lit. [α]D 25 +7.2° (c 1.0, H2O)); IR (KBr disk) 3420 (w, br), 3180 (w), 2700 (w), 2400-2260 (w), 1620 (w), 1560 (m), 1260 (m), 1089 (s), 1045 (s), 1000 (s), 970 (s), 740 (m), 810 (m) cm-1 ; 1H NMR (300 MHz, D2O+DC1)δ 4.37-4.27 (m, 2H, CH-CHH), 4.26-4.16 (m, 1H, CHH)31 ; 31p NMR (161.96 MHz, D2O+DC1) -0.45 (br (s). Anal. Calc. for C3H3NO6P: C, 19.47; H, 4.35; N, 7.57. Found: C, 19.27; H, 4.29; N, 7.82; POSFAB-MS (glycerol/HC1 ) 186 (MH+), 371 (M2H+); Rf 0.43 (System A).

Provenance & Evidence