Hydrogen Bromide → HCID 178480832, compound

HRID 1529583Notes

Reaction equation

HRID 1529583 reaction equation
[CH3:1][C:2]1[CH:7]=[C:6]([C:8]([O:10]C)=[O:9])[CH:5]=[CH:4][C:3]=1[C:12]1[CH:17]=[CH:16][C:15]([C:18]([O:20]C)=[O:19])=[CH:14][C:13]=1[CH3:22].[Br:23][N:24]1[C:28](=O)[CH2:27]C[C:25]1=O.CC(N=NC(C#N)(C)C)([C:34]#[N:35])C.[CH3:43][N:44]1[CH:48]=[CH:47][N:46]=[CH:45]1.[Br-:49].[NH+]1C=CNC=1.[Li+].[OH-].Br>C1COCC1.O.CC#N.CCOC(C)=O.C(Cl)(Cl)(Cl)Cl>[Br-:23].[C:18]([C:15]1[CH:16]=[CH:17][C:12]([C:3]2[CH:4]=[CH:5][C:6]([C:8]([OH:10])=[O:9])=[CH:7][C:2]=2[CH2:1][N+:46]2[CH:47]=[CH:48][N:44]([CH3:43])[CH:45]=2)=[C:13]([CH2:22][N+:35]2[CH:27]=[CH:28][N:24]([CH3:25])[CH:34]=2)[CH:14]=1)([OH:20])=[O:19].[Br-:49]

Participants

13

Reactant 7

HCID 260Hydrogen BromideHCID 13901-MethylimidazoleHCID 3939Lithium HydroxideHCID 6547AzobisisobutyronitrileHCID 67184N-bromobutanimideHCID 18622956101023-55-6HCID 73427287HCID 73427287, compound

Product 1

HCID 178480832HCID 178480832, compoundYield 45%

Reagents, catalysts & solvents 5

HCID 962WaterSolventHCID 5943Carbon TetrachlorideSolventHCID 6342AcetonitrileSolventHCID 8028TetrahydrofuranSolventHCID 8857Ethyl AcetateSolvent

Conditions

Temperature
80 °C

Procedure

To a 50 ml round bottom flask containing a stir bar is added 2 (1.21 g, 4.06 mmol), N-bromo succinimide (1.59 g, 8.94 mmol), AIBN (0.066 g, 0.406 mmol) and CCl4 (20 ml). The flask is fitted with a reflux condenser and refluxed for 3 hours or until TLC (30% EtOAc/Hex) shows full conversion. The contents of the flask are directly filtered into a 50 ml round bottom flask to remove the succinimide and the filtrate is concentrated under reduced pressure to yield a pale yellow oil. This oil is dried under high vacuum overnight. A stir bar is added to the flask containing the crude brominated compound and CH3CN (20 ml) and 1-methyl imidazole (0.73 ml, 8.94 mmol) are added. The flask is fitted with a reflux condenser and heated at 80° C. for 2 hours. After cooling to room temperature, the reaction mixture is transferred to a 100 ml round bottom flask and concentrated under reduced pressure to yield a brown oil. This oil is dried under high vacuum yielding the crude imidazolium bromide as a tan foam. To the flask containing the crude imidazolium bromide is added a stir bar and the foam is dissolved in 40 ml of a 1:1 THF:H2O mixture. LiOH (1.66 g, 40.6 mmol) is added in one portion and the reaction stirred for three hours at 23° C. After three hours, the reaction mixture is acidified to pH 1 with HBr (conc., 48% w/w) and the THF is removed under reduced pressure. After ˜20 ml of solvent is removed the contents of the flask are filtered to remove any solid and the filtrate is left to crystallize. After ˜24 hours white needle crystals began to fall out of solution. In subsequent reactions the filtrate is seeded with product. The crystals are filtered, washed with water, and dried under high vacuum yielding 4 (1.076 g, 45%) as a white crystalline solid. Analytical data for 4: IR (ATR) 3383, 2972, 1710, 1379, 1284, 1261, 1161, 952 cm−1; 1H NMR (500 MHz, DMSO-d6) δ8.73 (s, 2H), 8.01 (s, 2H), 7.96 (d, J=9.2 Hz, 2H), 7.66 (s, 2H), 7.43 (s, 2H), 7.18 (d, J=8.9 Hz) 5.24 (dd, J=104 Hz), 3.77 (s, 3H); 13C (125 MHz, DMSO-d6) δ 166.6, 142.2, 136.8, 132.5, 131.4, 130.7, 130, 129.8, 123.8, 122.5, 50.2, 35.9; HRMS (CI): Exact mass calcd for C24H24O4N4 [M/2]+, 216.09. Found: 216.1.

Workup

  1. additionTo a 50 ml round bottom flask containing a stir bar
  2. customThe flask is fitted with a reflux condenser
  3. filtrationThe contents of the flask are directly filtered into a 50 ml round bottom flask
  4. customto remove the succinimide
  5. concentrationthe filtrate is concentrated under reduced pressure
  6. customto yield a pale yellow oil
  7. customThis oil is dried under high vacuum overnight
  8. additionA stir bar is added to the flask
  9. additionare added
  10. customThe flask is fitted with a reflux condenser
  11. temperatureAfter cooling to room temperature
  12. customthe reaction mixture is transferred to a 100 ml round bottom flask
  13. concentrationconcentrated under reduced pressure
  14. customto yield a brown oil
  15. customThis oil is dried under high vacuum
  16. customyielding the crude imidazolium bromide as a tan foam
  17. additionis added a stir bar
  18. waitAfter three hours
  19. customthe THF is removed under reduced pressure
  20. customAfter ˜20 ml of solvent is removed the contents of the flask
  21. filtrationare filtered
  22. customto remove any solid
  23. waitthe filtrate is left
  24. customto crystallize
  25. waitAfter ˜24 hours white needle crystals began
  26. filtrationThe crystals are filtered
  27. washwashed with water
  28. customdried under high vacuum

Sources & evidence

ORD record
ord-f7d3d4c5ee884548a5d827457d4492b1
Source dataset
uspto-grants-2015_07
Patent number
US09090634B2

Reaction notes

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