Dimethylformamide → 4,7-Dichloro-6-nitroquinazoline

HRID 1838539Notes

Reaction equation

HRID 1838539 reaction equation
[Cl:1][C:2]1[CH:11]=[C:10]2[C:5]([C:6](=O)[NH:7][CH:8]=[N:9]2)=[CH:4][C:3]=1[N+:13]([O-:15])=[O:14].P(Cl)(Cl)([Cl:18])=O.CN(C=O)C>S(Cl)(Cl)=O>[Cl:18][C:6]1[C:5]2[C:10](=[CH:11][C:2]([Cl:1])=[C:3]([N+:13]([O-:15])=[O:14])[CH:4]=2)[N:9]=[CH:8][N:7]=1

Participants

5

Reactant 3

HCID 6228DimethylformamideHCID 24813Phosphorus oxychlorideHCID 1356875047-Chloro-6-nitroquinazolin-4(1H)-one

Product 1

HCID 104904554,7-Dichloro-6-nitroquinazolineYield 81%

Reagents, catalysts & solvents 1

HCID 24386Thionyl ChlorideSolvent

Procedure

A mixture of 7-chloro-6-nitro-3,4-dihydroquinazolin-4-one (40 g, 0.18 mol), (J. Org. Chem. 1975, 40, 356), phosphorus oxychloride (50 ml) and DMF (1 ml) in thionyl chloride (300 ml) was heated at reflux for 4 hours. The reaction mixture was allowed to cool and the volatiles removed by evaporation and by azeotroping with toluene. The residue was basified with aqueous sodium hydrogen carbonate solution and extracted with methylene chloride (4×100 ml). The extracts were combined, washed with brine and filtered through phase separating paper. The solvent was removed by evaporation and the residue triturated with ether/isohexane to give 4,7-dichloro-6-nitroquinazoline (35.2 g, 81%) as a pale yellow solid.

Workup

  1. temperaturewas heated
  2. temperatureat reflux for 4 hours
  3. temperatureto cool
  4. customthe volatiles removed by evaporation
  5. customby azeotroping with toluene
  6. extractionextracted with methylene chloride (4×100 ml)
  7. washwashed with brine
  8. filtrationfiltered through phase
  9. customseparating paper
  10. customThe solvent was removed by evaporation
  11. customthe residue triturated with ether/isohexane

Sources & evidence

ORD record
ord-9337bab50e5f4d94846c3b598158b530
Source dataset
uspto-grants-2004_01
Patent number
US06673803B2

Reaction notes

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