Benzene → 4-(Bromomethyl)benzophenone

HRID 1531315Notes

Reaction equation

HRID 1531315 reaction equation
[CH3:1][C:2]1[CH:15]=[CH:14][C:5]([C:6]([C:8]2[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=2)=[O:7])=[CH:4][CH:3]=1.[Br:16]Br.C1C=CC=CC=1>C(OCC)C>[Br:16][CH2:1][C:2]1[CH:15]=[CH:14][C:5]([C:6]([C:8]2[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=2)=[O:7])=[CH:4][CH:3]=1

Participants

5

Reactant 3

HCID 241BenzeneHCID 86524-MethylbenzophenoneHCID 24408Bromine2×

Product 1

HCID 1229514-(Bromomethyl)benzophenone

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Conditions

Temperature
70 °C

Procedure

30 g (0.153 mol) of 4-methylbenzophenone are introduced into a 250 ml three-necked flask equipped with a reflux condenser and a dropping funnel containing 8.7 ml (0.168 mol) of bromine. In a first step, the reaction medium is heated to 70° C. and then, after complete dissolution of the solid, to 150° C. The bromine is then added dropwise over a period of 3 hours. The reaction is exothermic. The initially colorless solution becomes orange-yellow. Heating is maintained at 150° C. for 15 hours. At the end of the reaction, the temperature of the reaction medium is allowed to return to room temperature. The solution is brown in color. 75 ml of benzene and 35 ml of diethyl ether are added. Washing is carried out with a saturated Na2CO3 solution, then with a saturated Na2S2O3 solution and finally with a saturated NaCl solution, in order to remove the salts formed and to bring the solution to a pH of the order of 6-7. The organic phase is recovered and the solvents are evaporated. A caramel-colored paste is obtained. It is recrystallized from 100 ml of ethanol. The cream-colored crystals are collected and dried under vacuum. The mother liquors are collected and a second crystallization is carried out. The crystals obtained are dried under vacuum. The yield of expected product is 50%, m=20.81 g.

Workup

  1. customequipped with a reflux condenser and a dropping funnel
  2. dissolutionafter complete dissolution of the solid
  3. customto 150° C
  4. temperatureHeating
  5. temperatureis maintained at 150° C. for 15 hours
  6. customAt the end of the reaction
  7. customto return to room temperature
  8. washWashing
  9. customwith a saturated Na2S2O3 solution and finally with a saturated NaCl solution, in order to remove the salts
  10. customformed
  11. customThe organic phase is recovered
  12. customthe solvents are evaporated
  13. customA caramel-colored paste is obtained
  14. customIt is recrystallized from 100 ml of ethanol
  15. customThe cream-colored crystals are collected
  16. customdried under vacuum
  17. customThe mother liquors are collected
  18. customa second crystallization
  19. customThe crystals obtained
  20. customare dried under vacuum

Sources & evidence

ORD record
ord-aa6b880b97284ef6bb4204f4ebd34bf7
Source dataset
uspto-grants-2001_03
Patent number
US06197842B1

Reaction notes

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