Phosphorus oxychloride → N-[3-(6-chloro-3-pyridazinyl)phenyl]propanamide

HRID 35628Notes

Reaction equation

HRID 35628 reaction equation
O=[C:2]1[NH:7][N:6]=[C:5]([C:8]2[CH:9]=[C:10]([NH:14][C:15](=[O:18])[CH2:16][CH3:17])[CH:11]=[CH:12][CH:13]=2)[CH:4]=[CH:3]1.P(Cl)(Cl)([Cl:21])=O>O1CCCC1>[Cl:21][C:2]1[N:7]=[N:6][C:5]([C:8]2[CH:9]=[C:10]([NH:14][C:15](=[O:18])[CH2:16][CH3:17])[CH:11]=[CH:12][CH:13]=2)=[CH:4][CH:3]=1

Participants

4

Reactant 2

HCID 24813Phosphorus oxychloride3×HCID 15595700N-[3-(1,6-Dihydro-6-oxo-3-pyridazinyl)phenyl]propanamide

Product 1

HCID 14280296N-[3-(6-chloro-3-pyridazinyl)phenyl]propanamide

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a refluxing solution of 0.63 g of N-[3-(1,6-dihydro-6-oxo-3-pyridazinyl)phenyl]propanamide in 100 ml of dry tetrahydrofuran was added 0.5 ml of phosphorus oxychloride. After 1.5 hours, 0.5 ml of phosphorus oxychloride was added and after 2 hours of refluxing 0.25 ml of phosphorus oxychloride was added. The solution was refluxed for an additional hour, then the solvent was removed, dichloromethane was added and the solution was poured into ice water. The mixture was neutralized with sodium bicarbonate and extracted with dichloromethane. The extracts were combined, washed with water, dried and the solvent removed giving an oil. This oil was chromatographed on thick layer silica gel preparative plates with dichloromethane:methanol (95:5), as solvent to give 0.33 g of solid. Recrystallization of 0.15 g from dichloromethane-acetone-hexane gave the desired compound as white crystals, mp 188°-189° C.

Workup

  1. additionwas added
  2. temperatureThe solution was refluxed for an additional hour
  3. customthe solvent was removed
  4. additiondichloromethane was added
  5. additionthe solution was poured into ice water
  6. extractionextracted with dichloromethane
  7. washwashed with water
  8. customdried
  9. customthe solvent removed
  10. customgiving an oil
  11. customThis oil was chromatographed on thick layer silica gel preparative plates with dichloromethane:methanol (95:5), as solvent

Sources & evidence

ORD record
ord-48d35dcd5d454d72812cd579886819d4
Source dataset
uspto-grants-1988_08
Patent number
US04767765

Reaction notes

Loading…