Sodium Bicarbonate → 3-Bromo-6-pyridin-3-ylpyrazolo[1,5-a]pyrimidine

HRID 1255858Notes

Reaction equation

HRID 1255858 reaction equation
[N:1]1[CH:6]=[CH:5][CH:4]=[C:3](B(O)O)[CH:2]=1.[Br:10][C:11]1[CH:12]=[N:13][N:14]2[CH:19]=[C:18](Br)[CH:17]=[N:16][C:15]=12.C(=O)(O)[O-].[Na+]>CN(C=O)C>[Br:10][C:11]1[CH:12]=[N:13][N:14]2[CH:19]=[C:18]([C:3]3[CH:2]=[N:1][CH:6]=[CH:5][CH:4]=3)[CH:17]=[N:16][C:15]=12

Participants

5

Reactant 3

HCID 516892Sodium BicarbonateHCID 27343783-Pyridinylboronic acidHCID 122032093,6-Dibromopyrazolo(1,5-a)pyrimidine

Product 1

HCID 687770603-Bromo-6-pyridin-3-ylpyrazolo[1,5-a]pyrimidine

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
85 °C

Procedure

A solution of 3-pyridyl boronic acid (1.33 g, 10.8 mmol) and 3,6-dibromopyrazolo[1,5-a]pyrimidine (3.0 g, 10.8 mmol) in DMF (300 mL) and 1M aqueous sodium bicarbonate (22 mL, 22 mmol) was degassed with nitrogen and treated with palladium tetrakistriphenylphosphine (0.63 g, 0.54 mmol) and heated to 85° C. for 16 hours. The reaction was cooled to room temperature and partitioned between water/methylene chloride. The organics were washed with water and brine, dried over sodium sulfate, filtered and evaporated in vacuo. Purification by flash chromatography (1-5% methanol/methylene chloride) gave 3-bromo-6-pyridin-3-ylpyrazolo[1,5-a]pyrimidine. LC-MS EIMS: m/z 275.0 [M+H]+.

Workup

  1. temperatureThe reaction was cooled to room temperature
  2. custompartitioned between water/methylene chloride
  3. washThe organics were washed with water and brine
  4. dry with materialdried over sodium sulfate
  5. filtrationfiltered
  6. customevaporated in vacuo
  7. customPurification by flash chromatography (1-5% methanol/methylene chloride)

Sources & evidence

ORD record
ord-ffdaa4444e3548e5a0996494f2ff854a
Source dataset
uspto-grants-2013_06
Patent number
US08461162B2

Reaction notes

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