Methyl iodide → N-Boc-N-methyl-3-(biphenyl-4-yl)-D-alanine

Participants

Reaction Steps

3-(1,1′-Biphenyl-4-yl)-2-tert-butoxycarbonylaminopropionic acid (5.0 g; 14.66 mmol) was dissolved in dry tetrahydrofuran (45 mL). Iodomethane (7.3 mL; 117.3 mmol) was added and the reaction mixture was cooled to 00 C. Sodium hydride (1.75 g; 44.0 mmol) was added and the reaction mixture was stirred for 5 days at room temperature. Ethyl acetate (50 mL) was added and water (20 mL) was added dropwise. The solvent was removed in vacuo and the residue was dissolved in an aqueous solution of sodium hydrogen carbonate (saturated; 50 mL) and washed with diethyl ether (30 mL). The aqueous phase was acidified to pH 3 using citric acid (5%) and extracted with ethyl acetate (3×50 mL). The organic phase was washed with an aqueous solution of sodium thiosulfate (5%; 75 mL) and dried (magnesium sulfate). The solvent was removed in vacuo to afford 3.85 g of (2R)-3-(1,1′-biphenyl-4-yl)-2-(N-tert-butoxycarbonyl-N-methylamino)propionic acid.

Provenance & Evidence