Sulfuric Acid → 2-bromo-6-methoxy-4-nitroaniline

HRID 990193Notes

Reaction equation

HRID 990193 reaction equation
[Br:1][C:2]1[CH:8]=[C:7]([N+:9]([O-:11])=[O:10])[CH:6]=[C:5]([O:12][CH3:13])[C:3]=1[NH2:4].S(=O)(=O)(O)O.N([O-])=O.[Na+]>O>[Br:1][C:2]1[CH:8]=[C:7]([N+:9]([O-:11])=[O:10])[CH:6]=[C:5]([O:12][CH3:13])[C:3]=1[NH2:4].[Br:1][C:2]1[CH:3]=[C:5]([O:12][CH3:13])[CH:6]=[C:7]([N+:9]([O-:11])=[O:10])[CH:8]=1

Participants

6

Reactant 3

HCID 1118Sulfuric AcidHCID 70991182-bromo-6-methoxy-4-nitroanilineHCID 23668193Sodium Nitrite

Product 2

HCID 70991182-bromo-6-methoxy-4-nitroanilineHCID 122990761-Bromo-3-methoxy-5-nitrobenzene

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Conditions

Temperature
0 °C

Procedure

A mixture of 2-bromo-6-methoxy-4-nitroaniline, as described above in Step A, (450 mg, 1.82 mmol) in water (40 mL) was cooled to 0° C. and treated with sulfuric acid (1.1 mL) followed by a solution of sodium nitrite (125 mg, 1.82 mmol) in water (0.5 mL) via pipet over 5 minutes. After stirring for 45 minutes at 0° C., the reaction was treated with ice cold 50% H3PO2 (10 mL) and stirred for 1.5 hours at 0° C. The reaction was quenched by adding aqueous saturated NaHCO3, filtered and dried overnight sitting in the hood to give an orange solid. This material was purified by column chromatography (5:1 hexane:ethyl acetate) to give 2-bromo-6-methoxy-4-nitroaniline and 3-bromo-5-nitroanisole as an off-white solid.

Workup

  1. stirringstirred for 1.5 hours at 0° C
  2. customThe reaction was quenched
  3. additionby adding aqueous saturated NaHCO3
  4. filtrationfiltered
  5. customdried overnight
  6. customto give an orange solid
  7. customThis material was purified by column chromatography (5:1 hexane:ethyl acetate)

Sources & evidence

ORD record
ord-d9a5ff951f1d4a1f84897fc2348e68c4
Source dataset
uspto-grants-2002_10
Patent number
US06458935B1

Reaction notes

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