Tert-butoxycarbonylalanine → 2-((S)-1-Aminoethyl)-5-fluoro-3-phenyl-3H-benzoimidazole-4-carboxylic acid methyl ester dihydrochloride

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-amino-6-fluoro-2-phenylaminobenzoic acid methyl ester (1 g, 3.8 mmol), Boc-ala-OH (727 mg, 3.8 mmol) and HOAT (522 mg, 3.8 mmol) in DCM (20 mL) at 0° C. was added N-(3-dimethylaminopropyl)-n′-ethylcarbodiimide hydrochloride (810 mg, 4.2 mmol) and the reaction mixture stirred at 0° C. for 2 h. The reaction mixture was diluted with water and extracted with DCM (3×10 mL). The combined organic fractions were washed with brine, dried (MgSO4) and concentrated in vacuo. The residue was dissolved in HCl in dioxane (20 mL, 4 M) and the reaction mixture heated at 75° C. for 45 min. The reaction mixture was concentrated in vacuo to give the title product as a dark purple solid (1.48 g, 100%). LCMS (Method C): RT=1.95 min, [M+H]+=314.

Provenance & Evidence