反应详情

A cooled (0° C.) suspension of 2′-fluoro-5′-nitrobiphenyl-2-carbonitrile (24.2 g, 100 mmol) in ethanol (150 ml) and tetrahydrofuran (150 ml) was treated with tin(II) chloride dihydrate (67.7 g, 300 mmol) and the mixture was stirred to ambient temperature over 12 h. The solvent was removed in vacuo and the residue treated with ice-cold 2N sodium hydroxide (750 ml). The resulting slurry was stirred for 60 min then extracted with dichloromethane (2×400 ml). The organics were combined, washed with water, brine, dried over anhydrous magnesium sulfate, filtered and concentrated to give a red solid. Crystallisation from toluene gave 5′-amino-2′-fluorobiphenyl-2-carbonitrile as a cream-coloured solid (16 g, 75%): δH (400 MHz, CDCl3) 3.65 (2H, br), 6.67-6.73 (2H, m), 7.00 (1H, t, J 9), 7.44-7.49 (2H, m), 7.64 (1H, td, J 9 and 2), 7.75 (1H, dd, J 8 and 2); m/z (ES+) 213 (M++H).

1. temperatureA cooled
2. customThe solvent was removed in vacuo
3. additionthe residue treated with ice-cold 2N sodium hydroxide (750 ml)
4. stirringThe resulting slurry was stirred for 60 min
5. extractionthen extracted with dichloromethane (2×400 ml)
6. washwashed with water, brine
7. dry with materialdried over anhydrous magnesium sulfate
8. filtrationfiltered
9. concentrationconcentrated
10. customto give a red solid
11. customCrystallisation from toluene