1-Hydroxybenzotriazole → 2-[(4-Bromo-1-hydroxy-naphthalene-2-carbonyl)-amino]-2-methyl-propionic acid methyl ester

Participants

Reaction Steps

To a solution of 1.5 g 4-bromo-1-hydroxy-2-naphthoic acid in 20 ml abs. DMF under inert atmosphere 0.84 g 1-hydroxybenzotriazole, 1.18 g 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride and 1.1 ml of N,N-diisopropylethylamine were added. After 15 minutes 0.86 g of 2-amino-2-methyl-propionic acid methyl ester hydrochloride, followed by 1.1 ml of N,N-diisopropylethylamine were added. After 24 h at room temperature and 2 h at 50° C. the reaction mixture was concentrated, the residue was taken up in ethyl acetate and washed with 2 M HCl, aqueous sodium carbonate solution (10%) and brine. The organic layer was dried over magnesium sulphate, and concentrated to yield 1.44 g of 2-[(4-bromo-1-hydroxy-naphthalene-2-carbonyl)-amino]-2-methyl-propionic acid methyl ester.

Provenance & Evidence