反应详情

A mixture of 3.92 g (16.4 mmol, 1 eq) of methyl[(3-amino-2-hydroxybenzoyl)methylamino]acetate and 4.68 g (32.9 mmol, 1 eq) of 3,4-dimethoxy-3-cyclobutene-1.2-dione was stirred at ambient temperature for 24 hours. The solvent was evaporated off and the residue was chromatographed on silica gel (200 g prepacked column, eluent 20/80 then 0/100 heptane/ethyl acetate). 3.49 g of methyl {[2-hydroxy-3-(2-methoxy-3,4-dioxocyclobut-1-enylamino)benzoyl]methylamino}acetate were obtained in the form of a white solid. Yield=61%.

1. customThe solvent was evaporated off
2. customthe residue was chromatographed on silica gel (200 g prepacked column, eluent 20/80