2-Amino-3-nitrophenol

Red-brown powder

2-Amino-3-nitrophenol has been used:

• as semipermanent (nonoxidative) hair colorant and as toner in permanent (oxidative) hair dye products
• as matrix during visible matrix-assisted laser desorption/ionization (VIS-MALDI) mass spectrometry
• in preparation of 1,3-benzoxazole-4,7-dione

Tin (II) chloride dihydrate (20 mmol) was dissolved in methanol (17.2 mL) under argon and added to the reaction flask; concentrated HCl (9.2 mL) was added slowly to the reaction system and the resulting solution was cooled to 0C. The dinitro compound was added to the reaction flask and the mixture was stirred overnight at room temperature, diluted with EtOAc and neutralized with saturated sodium bicarbonate. The inorganic salt solid was removed by filtration and the residue was washed with ethyl acetate, the filtrate and the separated phase were combined. The residual aqueous phase was extracted three times with ethyl acetate, the combined organic layers were dried with magnesium sulfate, the magnesium sulfate solids were removed by filtration, and the resulting organic filtrate was stripped of organic solvents under reduced pressure to afford the target product 2-amino-3-nitrophenol.