Phosphorus oxychloride → 4,6-Dichloro-1,7-naphthyridine-3-carbonitrile

HRID 276875Notes

Reaction equation

HRID 276875 reaction equation
[Cl:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][N:11]=1)[N:8]=[CH:7][C:6]([C:12]#[N:13])=[C:5]2O.P(Cl)(Cl)([Cl:17])=O>>[Cl:17][C:5]1[C:4]2[C:9](=[CH:10][N:11]=[C:2]([Cl:1])[CH:3]=2)[N:8]=[CH:7][C:6]=1[C:12]#[N:13]

Participants

3

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 178510322HCID 178510322, compound

Product 1

HCID 185489614,6-Dichloro-1,7-naphthyridine-3-carbonitrile

Procedure

To 650 mg of 6-chloro-4-hydroxy-[1.7]naphthyridine-3-carbonitrile under an inert atmosphere was added 20 mL of phosphorous oxychloride. After two hours at reflux, the excess phosphorous oxychloride was removed in vacuo and ice-water and chloroform were added. Solid potassium carbonate was then added carefully to a pH of about 8. The chloroform layer was washed with brine, dried with sodium sulfate, and stripped to give a crude product. This material was further purified by passing it through a plug of silica gel with 5% ethyl acetate/chloroform to give approximately 600 mg of 4,6-dichloro-[1.7]naphthyridine-3-carbonitrile as a yellowish solid, which was used in the following step.

Workup

  1. temperatureAfter two hours at reflux
  2. customthe excess phosphorous oxychloride was removed in vacuo and ice-water and chloroform
  3. additionwere added
  4. additionSolid potassium carbonate was then added carefully to a pH of about 8
  5. washThe chloroform layer was washed with brine
  6. dry with materialdried with sodium sulfate
  7. customto give a crude product
  8. customThis material was further purified

Sources & evidence

ORD record
ord-3a9f3782f9ab44c1bb52554d2c1fc62d
Source dataset
uspto-grants-2002_03
Patent number
US06355636B1

Reaction notes

Loading…