Methyl iodide → N-Cbz-N-methyl-L-leucine

Participants

Reaction Steps

To a solution of N-Cbz-leucine (1.38 g, 5.2 mmol) in THF (15 mL) at 0° C. was added methyl iodide (2.5 mL, 40.1 mmol). Sodium hydride (60% dispersion in oil, 0.6 g, 15 mmol) was added cautiously, and the resultant mixture was stirred at room temperature for 24 h. The reaction mixture was diluted with EtOAc (25 mL) and water (2 mL) was added dropwise. The mixture was concentrated to dryness, and the residue was partitioned between ether (15 mL) and water (50 mL). The organic layer was extracted with saturated aqueous NaHCO3 (25 mL), and the combined aqueous extracts were acidified to pH 2 with 3N HCl. The product was extracted with EtOAc (3× 25 mL), dried over MgSO4, filtered, and concentrated to afford the title compound (1.41 g) as a yellow solid.

Provenance & Evidence