Sodium Carbonate → 4-(1-methyl-3,6-dihydro-2H-pyridin-4-yl)-3-nitro-pyridine

Temperatur

75 °C

To a solution of 4-chloro-3-nitro-pyridine (350 mg, 2.208 mmol) in Toluene (7.00 mL), Ethanol (1.75 mL) and sodium carbonate solution (aq) (2.21 mL of 1 M, 2.21 mmol) was added 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,6-dihydro-2H-pyridine (985.3 mg, 4.416 mmol), Pd2(dba)3 (60.66 mg, 0.07 mmol) and triphenyl phosphine (115.8 mg, 102.3 μL, 0.44 mmol). The mixture was stirred at 75° C. (reflux) for 18 hours. The reaction mixture was evaporated to dryness and the residue was partitioned between water (30 mL) and DCM (2×30 mL). The combined organics were washed with water (30 mL) and brine (30 mL), dried and evaporated to dryness to afford a dark brown oil which was purified by column chromatography on silica gel eluting with petroleum ether (A): ethyl acetate (B) (20-100% (B), 24 g, 30.0 CV, 35 mL/min) then ethyl acetate (A): methanol (B) (0-10% (B)) to afford 4-(1-methyl-3,6-dihydro-2H-pyridin-4-yl)-3-nitro-pyridine as a red oil (305 mg, 63%). MS (ES+) 220.1.

1. temperature(reflux) for 18 hours
2. customThe reaction mixture was evaporated to dryness
3. customthe residue was partitioned between water (30 mL) and DCM (2×30 mL)
4. washThe combined organics were washed with water (30 mL) and brine (30 mL)
5. customdried
6. customevaporated to dryness
7. customto afford a dark brown oil which
8. customwas purified by column chromatography on silica gel eluting with petroleum ether (A)

ORD-Eintrag

ord-065e5764285d4e309400d6613b34f239

Quelldatensatz

uspto-grants-2016_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09340546B2