Hydrochloric Acid → 9-Phenyl-9H-carbazole-3-boronic acid

HRID 2179845Notes

Reaction equation

HRID 2179845 reaction equation
Br[C:2]1[CH:3]=[CH:4][C:5]2[N:6]([C:15]3[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=3)[C:7]3[C:12]([C:13]=2[CH:14]=1)=[CH:11][CH:10]=[CH:9][CH:8]=3.C([Li])CCC.[B:26](OC)([O:29]C)[O:27]C.Cl>O1CCCC1>[C:7]1([N:6]2[C:5]3[CH:13]=[CH:14][C:2]([B:26]([OH:29])[OH:27])=[CH:3][C:4]=3[C:20]3[C:15]2=[CH:16][CH:17]=[CH:18][CH:19]=3)[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 8470Trimethyl borateHCID 189426243-Bromo-9-phenylcarbazoleHCID 178418339Butyllithium

Product 1

HCID 513584509-Phenyl-9H-carbazole-3-boronic acidYield 80%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

In a 500 mL three-neck flask were stirred 29 g (90 mmol) of 3-bromo-9-phenylcarbazole obtained by the above Step 3 described in Synthesis Example 1 and 200 mL of tetrahydrofuran (abbreviation: THF) at −78° C. to provide a solution. Then, 110 mL (69 mmol) of n-butyllithium (1.6 mol/L hexane solution) was dropped therein, and the mixture was stirred for 2 hours at the same temperature. Furthermore, 13 mL (140 mmol) of trimethyl borate was added therein, and the mixture was stirred for 24 hours at room temperature. After the reaction, 200 mL of 1.0 mol/L hydrochloric acid was added therein, and the mixture was stirred for 1 hour at room temperature. This mixture was washed with water, aqueous sodium hydroxide, and water in this order, and magnesium sulfate was added so that the moisture was removed. This suspending solution was filtered and the obtained filtrate was concentrated. Then, chloroform and hexane were added therein, ultrasonic waves were applied thereto, and then recrystallization thereof was performed. Accordingly, 21 g of a powdery white solid of 9-phenyl-9H-carbazol-3-boronic acid, which was the object of the synthesis, was obtained in a yield of 80% (synthesis scheme (b-1)).

Workup

  1. customobtained by the above Step 3
  2. customto provide a solution
  3. stirringthe mixture was stirred for 24 hours at room temperature
  4. additionwas added
  5. stirringthe mixture was stirred for 1 hour at room temperature
  6. washThis mixture was washed with water, aqueous sodium hydroxide, and water in this order, and magnesium sulfate
  7. additionwas added so that the moisture
  8. customwas removed
  9. filtrationThis suspending solution was filtered
  10. concentrationthe obtained filtrate was concentrated
  11. additionThen, chloroform and hexane were added
  12. customrecrystallization
  13. customthe object of the synthesis
  14. customwas obtained in a yield of 80% (synthesis scheme (b-1))

Sources & evidence

ORD record
ord-09f317dd8f924de492cbe3b623ecd4f7
Source dataset
uspto-grants-2015_06
Patent number
US09070883B2

Reaction notes

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