4-Methylmorpholine → Boc-Pro-Ser-NH2

Participants

Reaction Steps

To a solution of 1.00 g (4.65 mmoles) Boc-Pro-OH in 10 ml anhydrous tetrahydrofuran, 0.52 ml (4.65 mmoles) N-methylmorpholine, and 0.45 ml (4.65 mmoles) ethyl chloroformate are successively added at a temperature of -12° C. After stirring at this temperature for 2 minutes, a cold solution of 0.48 g (4.65 mmoles) H-Ser-NH2 (R. W. Hanson and H. N. Rydon, J. Chem. Soc., 836, 1964) in 10 ml dimethylformamide is added. The reaction mixture is stirred at -10° C. for 3 hours and at 20° C. for 1 hour, then filtered from salts and evaporated in vacuo. The residue is taken up with tetrahydrofuran, filtered, and the solution evaporated again in vacuo. By crystallization from methanol-diethylether 1.1 g of compound (1) are obtained: m.p. 138° C. [α]D25 -58.9° (c=1, MeOH); RfA =0.15; RfB =0.33.

Provenance & Evidence