Hydrochloric Acid → 4,6-Diaminoresorcinol Dihydrochloride

Participants

Reaction Conditions

Reaction Steps

A 500 mL, 3-necked, round-bottomed flask is charged with 150 mL of water, 21.4 g (0.1 mole) of 5-methoxy-2,4-dinitrophenol and 1.0 g of 10% palladium on carbon catalyst. The reaction is stirred under a nitrogen atmosphere for 3 to 4 minutes. The stirred reaction mixture is heated to 55° C. and hydrogen gas is sparged below the surface of the reaction mixture. After 10 minutes, 19.8 g (0.2 mole) of concentrated HCl is added through the condenser while hydrogenation is continued for 4 hours. The catalyst is removed by filtration and the filtrate is passed into a solution consisting of 0.5 g of stannous chloride dihydrate and 25 mL of concentrated HCl. This solution is then saturated with dry HCl gas and charged to a 600 mL 5 Hastalloy B autoclave. The reactor is heated to 150° C. for 18 hours and cooled to 25° C. The resulting product is isolated by filtration and dried under nitrogen to yield 19.7 g (90% yield) of crude 4,6-diaminoresorcinol dihydrochloride.

Provenance & Evidence