Sulfuric Acid → 2-(Ethyl(3-methyl-4-nitrosophenyl)amino)ethanol

Participants

Reaction Steps

360 g of N-ethyl-N-(2-hydroxyethyl)-m-toluidine and 1,250 g of water are initially introduced into a stirred flask. 196 g of concentrated sulfuric acid are added, while stirring and cooling. During this addition, the internal temperature should not rise above 50°. After cooling to 0°, 187 g of isopropyl nitrite is allowed to run in slowly at -2° to +2°. The excess of nitrite is then removed in the customary manner with amidosulfonic acid. The reaction mixture is brought to room temperature and degassed under reduced pressure. 60 g of prereduced Pd/C (5%) is added to this solution as the catalyst and the N-ethyl-N-(2-hydroxyethyl)-3-methyl-4-nitroso-aniline, which has not been isolated, is hydrogenated at 20° to 40° under a gauge pressure of 0.4 bar of hydrogen. When the reaction has ended, the reaction batch is let down, the catalyst is filtered off and the reaction mixture is concentrated.

Provenance & Evidence