Reaktion #1518745

Reaktionsgleichung

2,5-dibromo-3-nitropyridine

6-methoxypyridin-3-ylboronic acid

sodium carbonate

→

5-bromo-6′-methoxy-3-nitro-2,3′-bipyridine

Lösungsmittel

1,4-dioxane

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe reaction was cooled to rt
2. 2
   ExtraktionAfter extraction with EtOAc
3. 3
   Extraktionthe organic extraction
4. 4
   Trocknenwas dried over anhydrous sodium sulfate
5. 5
   FiltrationAfter filtration and concentration
6. 6
   Sonstigethe residue was purified on silica gel (0-20% EtOAc in hexanes)

Vorschrift

A stirred mixture of 2,5-dibromo-3-nitropyridine (1.57 g, 5.57 mmol), 6-methoxypyridin-3-ylboronic acid (1.03 g, 6.73 mmol), trans-dichlorobis(triphenylphosphine)palladium (II) (0.2 g, 0.28 mmol), and 2.0M sodium carbonate (8.4 mL, 16.8 mmol) in 1,4-dioxane (27 mL) was heated to 90° C. After 19 h, the reaction was cooled to rt then diluted with water. After extraction with EtOAc, the organic extraction was dried over anhydrous sodium sulfate. After filtration and concentration, the residue was purified on silica gel (0-20% EtOAc in hexanes) to afford a light yellow solid as 5-bromo-6′-methoxy-3-nitro-2,3′-bipyridine. 1H NMR (400 MHz, CDCl3) δ ppm 8.92 (1H, d, J=2.2 Hz), 8.40 (1H, dd, J=2.5, 0.6 Hz), 8.32 (1H, d, J=2.2 Hz), 7.78 (1H, dd, J=8.6, 2.5 Hz), 6.85 (1H, dd, J=8.7, 0.7 Hz), 4.02 (3H, s).

Quelle