Pyridine → 2-Chloro-5-methyl-3-nitropyridine

HRID 72644Notes

Reaction equation

HRID 72644 reaction equation
[CH3:1][C:2]1[CH:3]=[C:4]([N+:9]([O-:11])=[O:10])[C:5](=O)[NH:6][CH:7]=1.N1C=CC=CC=1.P(Cl)(Cl)([Cl:20])=O.C(=O)([O-])[O-].[Na+].[Na+]>ClC1C=CC=CC=1>[Cl:20][C:5]1[C:4]([N+:9]([O-:11])=[O:10])=[CH:3][C:2]([CH3:1])=[CH:7][N:6]=1

Participants

6

Reactant 4

HCID 1049PyridineHCID 10340Sodium CarbonateHCID 24813Phosphorus oxychlorideHCID 3456432-Hydroxy-5-methyl-3-nitropyridine

Product 1

HCID 8183002-Chloro-5-methyl-3-nitropyridineYield 75.3%

Reagents, catalysts & solvents 1

HCID 7964ChlorobenzeneSolvent

Procedure

A solution of 5-methyl-3-nitro-1H-pyridone (3.1 g, 20 mmol) in 50 mL chlorobenzene was treated with pyridine (0.47 g, 6.0 mmol) and phosphorus oxychloride (4.7 g, 30.8 mmol). The mixture was refluxed for 1 h. Upon cooling it was treated with sodium carbonate aq. followed by extraction with CH2Cl2. The organic phase was dried over Mg2SO4 and filtered. The solvent was evaporated in vacuo to give 2.6 g of the titled compound which was further purified by flash chromatography on silica gel (PE:EtOAc, 8:2, v/v). 1H-NMR (CDCl3) δ: 2.45 (s, 3H, CH3), 8.44 (d, 1H, J=2.0 Hz, Py-H), 8.58 (d, 1H, J=2.0 Hz, Py-H); MS (ESI+) m/z 173.0209 [M+H]+, C6H5ClN2O2 requires 172.0040.

Workup

  1. temperatureThe mixture was refluxed for 1 h
  2. temperatureUpon cooling it
  3. extractionfollowed by extraction with CH2Cl2
  4. dry with materialThe organic phase was dried over Mg2SO4
  5. filtrationfiltered
  6. customThe solvent was evaporated in vacuo

Sources & evidence

ORD record
ord-bc06ef7e8e45493bbceced2dbb99d141
Source dataset
uspto-grants-2014_09
Patent number
US08829003B2

Reaction notes

Loading…