Sulfuric Acid → 2-Tert-butyl-5-nitrophenol

Participants

Reaction Conditions

Reaction Steps

In a 250 ml round bottom flask, 20 mL concentrated H2SO4 was added to 2-tert-butyl-5-nitro-aniline (7.15 g) by adding 5 mL aliquots of acid and sonicating with occasional heating until all of the starting aniline went into solution. H2O (84 ml) was added with stirring, then the reaction was cooled to 0° C. forming a yellow-orange suspension. A solution of NaNO2 (2.792 g) in H2O (11.2 mL) was added dropwise to the suspension and stirred for 5 min. Excess NaNO2 was neutralized with urea, then the cloudy solution was transferred to 500 ml 3-necked round bottom flask then added 17 mL of 1:2 H2SO4:H2O solution, and heated at reflux. Two additional 5 mL aliquots of 1:2 H2SO4:H2O solution, a 7 mL aliquot of 1:2 H2SO4:H2O solution and another 10 mL of 1:2 H2SO4: H2O were added while heating at reflux. The mixture was cooled to RT forming a black layer floating on top of the aqueous layer. The black layer was diluted with EtOAc (300 mL) and separated. The organic layer was washed with H2O then brine, dried over Na2SO4 and concentrated in vacuo. Crude oil was purified on silica gel column with 8% EtOAc/Hexanes. Upon drying under vacuum, the 2-tert-butyl-5-nitrophenol was isolated as a brown solid.

Provenance & Evidence