Potassium Carbonate → 3-Chloro-5-ethynylpyridine

HRID 606807Notes

Reaction equation

HRID 606807 reaction equation
C(=O)([O-])[O-].[K+].[K+].[Cl:7][C:8]1[CH:9]=[N:10][CH:11]=[C:12]([C:14]#[C:15][Si](C)(C)C)[CH:13]=1>CO>[Cl:7][C:8]1[CH:9]=[N:10][CH:11]=[C:12]([C:14]#[CH:15])[CH:13]=1

Participants

4

Reactant 2

HCID 11430Potassium CarbonateHCID 235008913-Chloro-5-[2-(trimethylsilyl)ethynyl]pyridine

Product 1

HCID 235008873-Chloro-5-ethynylpyridineYield 52.5%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

Add potassium carbonate (4.35 g, 31.5 mmol) to a solution of 3-chloro-5-trimethylsilanylethynyl-pyridine (5.51 g, 26.3 mmol), (prepared as described in PREPARATION 26), in methanol (120 mL) and stir for 2 h. Concentrate, add water (150 mL), and extract with diethyl ether (2×100 mL). Wash the organic phase with an aqueous saturated solution of sodium chloride (100 mL), dry (sodium sulfate), filter, and concentrate. Purify the residue by silica gel chromatography, eluting with 20:80 ethyl acetate:hexanes to give the title compound as a pale yellow solid (1.9 g, 52%).

Workup

  1. concentrationConcentrate
  2. additionadd water (150 mL)
  3. extractionextract with diethyl ether (2×100 mL)
  4. washWash the organic phase with an aqueous saturated solution of sodium chloride (100 mL)
  5. dry with materialdry (sodium sulfate)
  6. filtrationfilter
  7. concentrationconcentrate
  8. customPurify the residue by silica gel chromatography
  9. washeluting with 20:80 ethyl acetate

Sources & evidence

ORD record
ord-d2c8c916b6f74f96933c601652bffdd8
Source dataset
uspto-grants-2011_03
Patent number
US07915424B2

Reaction notes

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