M-Phenylenediamine → (S)-tert-butyl (1-((3-aminophenyl)amino)-1-oxopropan-2-yl)(methyl)carbamate

Participants

Reaction Steps

To N-Boc-N-methyl-L-alanine (1.02 g), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (1.92 g) and 1-hydroxybenzotriazole monohydrate (1.35 g), N,N-dimethylformamide (15 mL) was added at room temperature, and the mixture was stirred at the same temperature for 1 hour. To the reaction mixture, a solution of N,N-diisopropylethylamine (2.6 mL) and 1,3-phenylenediamine (1.35 g) in N,N-dimethylformamide (4 mL) was added at room temperature, and the mixture was stirred at 40° C. for 3 hours. The reaction mixture was cooled to room temperature, and then saturated aqueous sodium hydrogencarbonate and ethyl acetate were added to the mixture. The organic layer was separated, washed successively with water and saturated aqueous sodium chloride, and then dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The obtained residue was purified by silica gel column chromatography (eluent, 60 to 25% hexane in ethyl acetate) to obtain amorphous (S)-tert-butyl (1-((3-aminophenyl)amino)-1-oxopropan-2-yl)(methyl)carbamate (B9, 967 mg).

Provenance & Evidence