Sulfuric Acid → 3-Chloro-5-nitrobenzonitrile

HRID 2264134Notes

Reaction equation

HRID 2264134 reaction equation
OS(O)(=O)=O.N[C:7]1[C:14]([Cl:15])=[CH:13][C:12]([N+:16]([O-:18])=[O:17])=[CH:11][C:8]=1[C:9]#[N:10].CC(O)C.N([O-])=O.[Na+]>O>[Cl:15][C:14]1[CH:7]=[C:8]([CH:11]=[C:12]([N+:16]([O-:18])=[O:17])[CH:13]=1)[C:9]#[N:10]

Participants

6

Reactant 4

HCID 1118Sulfuric Acid2×HCID 3776IsopropanolHCID 88504Benzonitrile, 2-amino-3-chloro-5-nitro-HCID 23668193Sodium Nitrite

Product 1

HCID 6027173-Chloro-5-nitrobenzonitrile

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
40 °C

Procedure

Concentrated H2SO4 (440 mL) was added slowly to crushed ice (1200 g) and 2-amino-3-chloro-5-nitrobenzonitrile (43.8 g) was suspended in the resulting H2SO4 solution. After addition of 2-propanol (1600 mL), the mixture was heated to 40° C. internal temperature with vigorous stirring. A solution of NaNO2 (66.0 g) in water (100 mL) was added dropwise. After completion of addition, the mixture was kept at 40° C. for an additional 3 h, then cooled to ambient temperature and extracted with CH2Cl2. The organic extract was washed sequentially with water, 0.1 N NaOH, water, and brine, and then dried over MgSO4, filtered through a pad of silica gel, and evaporated to yield the crude product as a yellow solid. Chromatography on silica gel (20% EtOAc/hexanes) followed by crystallization from 2-propanol yielded the product as yellow crystals. 1H-NMR (CDCl3): δ 8.47 (1H, t, J=2.0 Hz), 8.43 (1H, dd, J=1.4, 2.0 Hz), 7.98 (1H, dd, J=1.4, 2.0 Hz). 13C-NMR (CDCl3): δ 148.8, 137.4, 137.0, 128.1, 125.3, 115.4, 115.3.

Workup

  1. additionAfter completion of addition
  2. temperaturecooled to ambient temperature
  3. extractionextracted with CH2Cl2
  4. extractionThe organic extract
  5. washwas washed sequentially with water, 0.1 N NaOH, water, and brine
  6. dry with materialdried over MgSO4
  7. filtrationfiltered through a pad of silica gel
  8. customevaporated
  9. customto yield the crude product as a yellow solid
  10. customChromatography on silica gel (20% EtOAc/hexanes) followed by crystallization from 2-propanol

Sources & evidence

ORD record
ord-dfaba3014b49400d9e0c2875b5f378cc
Source dataset
uspto-grants-2010_12
Patent number
US07855192B2

Reaction notes

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