Reaktion #732828

Reaktionsgleichung

N2

cesium carbonate

2-chloro-3-cyanopyridine

2-fluoropyridine-5-boronic acid

→

title compound

Ausbeute 84.5%

6′-fluoro-[2,3′]bipyridinyl-3-carbonitrile

Ausbeute 84.5%

Lösungsmittel

water

dioxane

Water

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeTo an oven-dried, N2-purged
2. 2
   workup.ADDITION250-mL, round-bottomed flask containing a magnetic stir bar
3. 3
   SonstigeThe flask was sealed with a septum
4. 4
   Sonstigepurged with N2 atmosphere
5. 5
   workup.ADDITIONwere added via syringe
6. 6
   TemperaturAfter cooling to room temperature
7. 7
   Sonstigethe solvent/volatiles were removed by rotary evaporator
8. 8
   Sonstigeto give a thick brown oil
9. 9
   Sonstigethe mixture was transferred to a separatory funnel
10. 10
    ExtraktionThe mixture was extracted with ethyl acetate (4×30 mL)
11. 11
    TrocknenThe combined organic extracts were dried over magnesium sulfate
12. 12
    Filtrationfiltered
13. 13
    Einengenconcentrated by rotary evaporator
14. 14
    Sonstigeto give a brown solid
15. 15
    SonstigeThe product was recrystallized from ethyl acetate/hexanes

Vorschrift

To an oven-dried, N2-purged, 250-mL, round-bottomed flask containing a magnetic stir bar were added the commercially available 2-chloro-3-cyanopyridine (1.25 g, 9.00 mmol), the commercially available 2-fluoropyridine-5-boronic acid (845 mg, 6.00 mmol), and dichlorobis(triphenylphosphine)palladium(II) (211 mg, 0.300 mmol). The flask was sealed with a septum and purged with N2 atmosphere. Anhydrous dioxane (45 mL) and a N2-purged solution of cesium carbonate (5.86 g, 18.0 mmol) in water (45 mL) were added via syringe. The reaction mixture was heated to ˜90° C. in an oil bath and stirred for 2 hours. The reaction was monitored by LC-MS. After cooling to room temperature, the solvent/volatiles were removed by rotary evaporator to give a thick brown oil. Water (75 mL) was added and the mixture was transferred to a separatory funnel. The mixture was extracted with ethyl acetate (4×30 mL). The combined organic extracts were dried over magnesium sulfate, filtered, and concentrated by rotary evaporator to give a brown solid. The product was recrystallized from ethyl acetate/hexanes to give 1.01 g (84%) of the title compound as a tan powder. MS (ESI+) m/z 200.0 (M+H)+; 1H NMR (DMSO-d6) δ 7.43 (dd, J=8.6, 2.9 Hz, 1H), 7.70 (dd, J=8.1, 5.1 Hz, 1H), 8.49 (d, J=1.7 Hz, 1H), 8.51 (d, J=1.7 Hz, 1H), 8.74 (d, J=2.7 Hz, 1H), 8.98 (dd, J=4.7, 1.7 Hz, 1H).

Quelle