Hydrogen Bromide → 6,7-Dihydroxy-4(3H)-quinazolinone

HRID 2423004Notes

Reaction equation

HRID 2423004 reaction equation
Br.C[O:3][C:4]1[CH:5]=[C:6]2[C:11](=[CH:12][C:13]=1[O:14]C)[N:10]=[CH:9][NH:8][C:7]2=[O:16]>>[OH:3][C:4]1[CH:5]=[C:6]2[C:11](=[CH:12][C:13]=1[OH:14])[N:10]=[CH:9][NH:8][C:7]2=[O:16]

Participants

3

Reactant 2

HCID 260Hydrogen BromideHCID 1354950166,7-Dimethoxy-3H-quinazolin-4-one

Product 1

HCID 1357422586,7-Dihydroxy-4(3H)-quinazolinoneYield 98.62%

Conditions

Temperature
30 °C

Procedure

Into a 2.0 Lt four necked round bottomed flask equipped with a mechanical stirrer, reflux condenser and thermometer socket are charged 48% (w/w) hydrobromic acid (1000 g) and 6,7-dimethoxy-4(3H)-quinazolinone (100 g). Slowly heated the reaction mass to reach 110° C. and maintained for 1 hour at the same temperature. Then raised mass temperature to reach reflux condition and refluxed for 12 hours. Monitored the completion of the reaction by TLC. Then cooled the reaction mass to 25-35° C. and filtered the mass. Transferred the wet cake into another 2.0 Lt round bottomed flask containing 1000 ml of DM water. Stirred for 10-15 minutes and adjusted the pH to 7.0-7.5, by adding aqueous ammonia solution. Filtered the resulting product and washed the cake with DM water and dried to get 85.2 g (98.62% by theory) of 6,7-dihydroxy-4(3H)-quinazolinone as off-white crystalline solid.

Workup

  1. customInto a 2.0 Lt four necked round bottomed flask equipped with a mechanical stirrer
  2. temperaturereflux condenser
  3. temperatureSlowly heated the reaction mass
  4. customto reach 110° C.
  5. temperaturemaintained for 1 hour at the same temperature
  6. temperatureThen raised mass temperature
  7. temperatureto reach reflux condition
  8. temperaturerefluxed for 12 hours
  9. customMonitored the completion of the reaction by TLC
  10. filtrationfiltered the mass
  11. additionTransferred the wet cake into another 2.0 Lt round bottomed flask containing 1000 ml of DM water
  12. additionby adding aqueous ammonia solution
  13. filtrationFiltered the resulting product
  14. washwashed the cake with DM water
  15. customdried

Sources & evidence

ORD record
ord-f13b0af4834f42a89f9ad79ca9c48b09
Source dataset
uspto-grants-2011_06
Patent number
US07960545B2

Reaction notes

Loading…