Hydrochloric Acid → Hydrochloric Acid

Participants

Reaction Steps

An amount of 210 g of 4-nitro-2-(2-carboxyethylamino)carbonyl-1-naphthol was dissolved in 28 liters of methanol at 40° C. Into this solution was added 1,200 ml conc. hydrochloric acid, followed subsequently by portionwise addition of 430 g of zinc powder. After 30 minutes, zinc was removed and the solvent was removed by evaporation under reduced pressure. The residue was dissolved in 25 liters of ethyl acetate, washed with water and then dried over magnesium sulfate, followed by evaporation of the solvent, to give crystals. The crystals were washed with acetonitrile to obtain substantially pure desired product as hydrochloride. Yield was 75%. The product was confirmed by NMR, Mass spectra.

Provenance & Evidence