Pyridine → HCID 21459007, compound

HRID 725366Notes

Reaction equation

HRID 725366 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]([CH:7]=[C:8]([N+:12]([O-:14])=[O:13])[C:9]=1[O:10][CH3:11])N.N([O-])=O.[Na+].[N:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1>Cl.O>[CH3:1][O:2][C:3]1[CH:4]=[C:5]([C:20]2[CH:21]=[CH:22][CH:23]=[CH:24][N:19]=2)[CH:7]=[C:8]([N+:12]([O-:14])=[O:13])[C:9]=1[O:10][CH3:11]

Participants

6

Reactant 3

HCID 1049PyridineHCID 21458940HCID 21458940, compoundHCID 23668193Sodium Nitrite

Product 1

HCID 21459007HCID 21459007, compound

Reagents, catalysts & solvents 2

HCID 313Hydrochloric AcidSolventHCID 962WaterSolvent2×

Procedure

10 g of finely powdered 3,4-dimethoxy-5-nitroaniline are suspended in 15 ml of 12N hydrochloric acid and 40 ml of water, whereupon the suspension is stirring at 30° for 1 hour. Thereupon, 3.8 g of sodium nitrite dissolved in 20 ml of water are added dropwise thereto at -5° within 15 minutes. The solution is stirred at -5° for 30 minutes and the cold diazonium salt solution is added dropwise within 45 minutes to 100 ml of pyridine of 40°. The mixture is subsequently stirred at 70° for 1 hour. The reaction mixture is evaporated and the residue is taken up in 300 ml of ethyl acetate. It is extracted three times with 200 ml of 2N hydrochloric acid each time. The acidic-aqueous phase is adjusted to pH 9 with conc. ammonia and extracted with methylene chloride. The combined methylene chloride extracts are dried over sodium sulfate and evaporated, and the residue is chromatographed on 250 g of silica gel with ethyl acetate. After crystallization from methylene chloride/hexane there is obtained 2-(3,4-dimethoxy-5-nitrophenyl)pyridine of m.p. 89°-90°.

Workup

  1. additionare added dropwise
  2. stirringThe mixture is subsequently stirred at 70° for 1 hour
  3. customThe reaction mixture is evaporated
  4. extractionIt is extracted three times with 200 ml of 2N hydrochloric acid each time
  5. extractionextracted with methylene chloride
  6. dry with materialThe combined methylene chloride extracts are dried over sodium sulfate
  7. customevaporated
  8. customthe residue is chromatographed on 250 g of silica gel with ethyl acetate
  9. customAfter crystallization from methylene chloride/hexane there

Sources & evidence

ORD record
ord-84a50aa668934625a672a80a62a693aa
Source dataset
uspto-grants-1998_01
Patent number
US05705703

Reaction notes

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