反应详情

LiHMDS (1M in toluene, 17.6 mL, 17.6 mmol, 3.1 eq) is added dropwise to a cold (−5° C.) mixture of 4-bromo-2-fluoro-pyridine [Marsais, F. et al, Journal of Organic Chemistry, (1992), 57, 565-573] (1 g, 5.7 mmol), cyclopropanecarbonitrile (1.25 mL, 17 mmol, 3 eq), 4 Å molecular sieves and toluene (20 mL). The reaction mixture is allowed to warm to rt, stirred for 16 h, poured into H2O and filtered. The filtrate is diluted with EtOAc/H2O and extracted with EtOAc. The organic phase is washed with H2O and brine, dried (Na2SO4), filtered and concentrated. The residue is purified by silica gel column chromatography (Hex/EtOAc, 9:1), to afford 620 mg of the title compound as a white solid: ESI-MS: 223.1/225.1 [M+H]+; tR=4.22 min (System 1); TLC: Rf=0.25 (Hex/EtOAc, 9:1).

1. filtrationfiltered
2. additionThe filtrate is diluted with EtOAc/H2O
3. extractionextracted with EtOAc
4. washThe organic phase is washed with H2O and brine
5. dry with materialdried (Na2SO4)
6. filtrationfiltered
7. concentrationconcentrated
8. customThe residue is purified by silica gel column chromatography (Hex/EtOAc, 9:1)