Water → 5'-Fluoro-5-nitro-3,3'-bipyridin-4-amine

Temperature

90 °C

A solution of 3-bromo-5-nitropyridin-4-amine (LXIX) (790 mg, 3.62 mmol), 3-fluoro-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (LXX) (1.01 g, 4.35 mmol), K3PO4 (1.15 g, 5.44 mmol), water (10 mL) and DMF (10 mL) was degassed with argon thrice. Pd(PPh3)4 (209 mg, 0.18 mmol) was added to the reaction and the solution was heated at 90° C. for 4 h. The reaction was passed through a pad of Celite and then concentrated under reduced pressure. The reaction mixture was concentrated and the residue was taken up in EtOAc. The organic extract was washed with water, dried and concentrated under vacuum. The crude product was purified on a silica gel column (100% CHCl3→1.5:98.5 MeOH[7N NH3]:CHCl3) to give 5′-fluoro-5-nitro-3,3′-bipyridin-4-amine (LXXI) as a yellow solid (626 mg, 2.67 mmol, 74% yield). 1H NMR (DMSO-d6, 500 MHz) δ ppm 7.62 (brs, 2H), 7.86-7.89 (m, 1H), 8.15 (s, 1H), 8.47-8.48 (m, 1H), 8.67 (d, J=2.7 Hz, 1H), 9.07 (s, 1H); ESIMS found C10H7FN4O2 m/z 235 (M+H).

1. concentrationconcentrated under reduced pressure
2. concentrationThe reaction mixture was concentrated
3. extractionThe organic extract
4. washwas washed with water
5. customdried
6. concentrationconcentrated under vacuum
7. customThe crude product was purified on a silica gel column (100% CHCl3→1.5:98.5 MeOH[7N NH3]:CHCl3)

ORD record

ord-ef21531e55e045bdaf1246ef01aed78d

Source dataset

uspto-grants-2014_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08883822B2