Benzenesulfonyl chloride → 2-Bromo-5-(phenylsulfonyl)-5H-pyrrolo[2,3-b]pyrazine

HRID 1052241Notes

Reaction equation

HRID 1052241 reaction equation
[Br:1][C:2]1[N:3]=[C:4]2[CH:10]=[CH:9][NH:8][C:5]2=[N:6][CH:7]=1.[H-].[Na+].[C:13]1([S:19](Cl)(=[O:21])=[O:20])[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1>O1CCCC1>[Br:1][C:2]1[N:3]=[C:4]2[CH:10]=[CH:9][N:8]([S:19]([C:13]3[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=3)(=[O:21])=[O:20])[C:5]2=[N:6][CH:7]=1

Participants

5

Reactant 3

HCID 7369Benzenesulfonyl chlorideHCID 24758Sodium hydrideHCID 250673082-bromo-5H-pyrrolo[2,3-b]pyrazine

Product 1

HCID 899634192-Bromo-5-(phenylsulfonyl)-5H-pyrrolo[2,3-b]pyrazineYield 88%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a stirred solution of 2-bromo-5H-pyrrolo[2,3-b]pyrazine (from Ark Pharm, cat# AK-23813, 1.00 g, 5.05 mmol) in tetrahydrofuran (10 mL), NaH (60% w/w dispersion form in mineral oil, 283 mg, 7.07 mmol) was added at 0° C. After 0.5 hour, benzenesulfonyl chloride (644 μL, 5.05 mmol) was added dropwise. After another 1 hour, the reaction mixture was quenched with saturated aqueous NH4Cl and extracted with methylene chloride. The combined organic layers were dried over MgSO4, filtered, and concentrated. The residue was purified on silica gel (eluting with 0 to 50% ethyl acetate (EtOAc) in hexanes) to give the desired product (1.50 g, 88%). LCMS calculated for C12H9BrN3O2S (M+H)+: m/z=339.2. Found: 339.2.

Workup

  1. waitAfter another 1 hour
  2. customthe reaction mixture was quenched with saturated aqueous NH4Cl
  3. extractionextracted with methylene chloride
  4. dry with materialThe combined organic layers were dried over MgSO4
  5. filtrationfiltered
  6. concentrationconcentrated
  7. customThe residue was purified on silica gel (eluting with 0 to 50% ethyl acetate (EtOAc) in hexanes)

Sources & evidence

ORD record
ord-23dfe4f5f6514cf294dbc6c2dd1c7c1a
Source dataset
uspto-grants-2016_07
Patent number
US09388185B2

Reaction notes

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