反应详情

温度

50 °C

A thick-walled glass pressure vessel was charged with 2-chloro-4-fluoro-3-iodobenzonitrile (2.815 g, 10.00 mmol), Pd(PPh3)2Cl2 (0.351 g, 0.500 mmol), and CuI (0.095 g, 0.500 mmol) and sealed with a rubber septum. Anhydrous THF (25 mL) and DIPA (4.22 mL, 30.0 mmol) were added via syringe and the mixture was degassed 10 min by sparging with N2 while immersed in an ultrasonic cleaning bath. To the degassed mixture was added ethynyltrimethylsilane (4.24 mL, 30.0 mmol), the vessel was resealed with a PTFE bushing, and the mixture was stirred in a heating block at 50° C. After 41 h, the mixture was cooled and poured into half-satd NH4Cl. The whole was filtered through a pad of Celite and the filtrate was extracted with EtOAc (×3). Combined organics were washed (water, brine), dried over Na2SO4 and concentrated in vacuo. The residue was purified by low pressure liquid chromatography (silica gel, EtOAc/hexanes, gradient elution) affording 2-chloro-4-fluoro-3-((trimethylsilyl)ethynyl)benzonitrile (2.29 g, 91% yield) as a pale yellow solid: 1H NMR (400 MHz, CDCl3) δ 7.60 (dd, J=8.7, 5.4 Hz, 1H), 7.12 (dd, J=8.7, 7.9 Hz, 1H), 0.30 (s, 9H); MS (GCMS EI) m/z 251 ([M]+, 14%), 236 ([M-CH3]+, 100%).

1. customsealed with a rubber septum
2. customthe mixture was degassed 10 min
3. customby sparging with N2
4. customwhile immersed in an ultrasonic cleaning bath
5. temperaturethe mixture was cooled
6. filtrationThe whole was filtered through a pad of Celite
7. extractionthe filtrate was extracted with EtOAc (×3)
8. washCombined organics were washed (water, brine)
9. dry with materialdried over Na2SO4
10. concentrationconcentrated in vacuo
11. customThe residue was purified by low pressure liquid chromatography (silica gel, EtOAc/hexanes, gradient elution)