Triphenylphosphine → 2-Chloro-4-(2-(trimethylsilyl)ethynyl)pyridine

2-Chloro-4-iodo-pyridine (10.0 g, 41.8 mmol) was dissolved in 200 mL of dry THF and 17.5 mL of triethyl amine. This mixture was evacuated and backfilled with argon several times to remove oxygen from the solution. Triphenylphosphine (329 mg, 1.25 mmol) and bis(triphenylphosphine)palladium(II)chloride (1.47 g, 2.09 mmol) were added and the reaction mixture was stirred at room temperature for 1 h. Copper(I)iodide (239 mg, 1.25 mmol) and trimethylsilylacetylene (6.28 g, 6.39 mmol) were added. The reaction mixture was stirred at room temperature overnight. The solvent was evaporated. The residue was taken up in 500 mL of water and extracted three times with ethyl acetate (500 mL each). The combined organic extracts were dried with magnesium sulfate, filtered and evaporated. The crude product was purified by chromatography on silica gel (cyclohexane/ethyl acetate 80:20). The desired product was obtained as a light brown semi solid (10 g,>100%). This material was used without any further purification for the next step.

1. customThis mixture was evacuated
2. customto remove oxygen from the solution
3. stirringThe reaction mixture was stirred at room temperature overnight
4. customThe solvent was evaporated
5. extractionextracted three times with ethyl acetate (500 mL each)
6. dry with materialThe combined organic extracts were dried with magnesium sulfate
7. filtrationfiltered
8. customevaporated
9. customThe crude product was purified by chromatography on silica gel (cyclohexane/ethyl acetate 80:20)

ORD record

ord-80181137367c4b76a0553b91aeaf1308

Source dataset

uspto-grants-2006_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07091222B2