Reaktion #73264

Reaktionsgleichung

3,5-dibromopyridine

1,4-dioxane

morpholine

sodium tert-butoxide

→

4-(5-bromopyridin-3-yl)morpholine

Ausbeute 41.1%

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe reaction was bubbled with nitrogen
2. 2
   Sonstigenitrogen was bubbled through for couple of minutes
3. 3
   Temperaturto cool to rt
4. 4
   Sonstigewas then partitioned between water and ethyl acetate
5. 5
   WaschenThe organic layer was washed with saturated sodium chloride
6. 6
   Trocknendried over magnesium sulfate
7. 7
   Filtrationfiltered
8. 8
   Einengenconcentrated
9. 9
   Sonstigeto give a crude residue
10. 10
    SonstigeThe crude product was purified by FCC on silica gel eluting with 1:1, EtOAC
11. 11
    SonstigeHexane gave

Vorschrift

To a solution of [3,5-dibromopyridine (1000 mg, 0.004 mol) in 1,4-dioxane (8 mL, 0.1 mol), morpholine (400 mg, 0.004 mol) and sodium tert-butoxide (400 mg, 0.004 mol) were added. The reaction was bubbled with nitrogen. Tetrakis(triphenylphosphine)palladium(0) (200 mg, 0.0002 mol) was added and nitrogen was bubbled through for couple of minutes. The mixture was heated at 80° C. overnight. The reaction was allowed to cool to rt and was then partitioned between water and ethyl acetate. The organic layer was washed with saturated sodium chloride, dried over magnesium sulfate, filtered and concentrated to give a crude residue. The crude product was purified by FCC on silica gel eluting with 1:1, EtOAC:Hexane gave to give 4-(5-bromopyridin-3-yl)morpholine as a viscous oil (400 mg, 40%). 1H NMR (400 MHz, CDCl3): 8.2 (s, 1H), 8.1 (s, 1H), 7.2 (s, 1H), 3.8 (m, 4H), 3.2 (m, 4H).

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