4-Methylmorpholine → N-(Toluene-4-sulfonyl)-L-alanyl-L-phenylalanine Benzyl Ester

Participants

Reaction Steps

To N-(toluene-4-sulfonyl)-L-alanine (2.0 mmoles) in DMF (10 mL) was added BOP (2.1 mmoles) and N-methylmorpholine (4.0 mmoles) and the reaction stirred at room temperature for 45 minutes. L-Phenylalanine benzyl ester (2.0 mmoles) was added and the reaction stirred for 16 hours at room temperature. The reaction mixture was extracted with water (100 mL) and diethyl ether (3×50 mL) The combined organic layers were successively washed with 0.2 N HCl (2×50 mL), sat. NaHCO3 (50 mL), and sat. NaCl (50 mL). The organic layer was dried over MgSO4, filtered, and concentrated to yield a colorless oil (387 mg, 40%). The crude product was purified by silica gel chromatography (50% EtOAc/Hexane, Rf=0.61). The title compound was crystalized from CHCl3/Hexane to yield a white solid, mp=109–110° C.

Provenance & Evidence