Reaktion #92603

Reaktionsgleichung

3-bromo-4-chloropyridine

hydrazine hydrate

→

3-bromo-4-hydrazinylpyridine

Ausbeute 87.0%

Lösungsmittel

isopropyl alcohol

dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturAfter cooling down to RT
2. 2
   Einengenthe mixture was concentrated
3. 3
   SonstigeThe residue was partitioned between 300 mL of EA and 300 mL of aq. sat. NH4Cl
4. 4
   WaschenThe organic layer was washed with brine
5. 5
   Trocknendried over Na2SO4
6. 6
   Filtrationfiltered
7. 7
   Einengenconcentrated
8. 8
   Sonstigeto get crude product which
9. 9
   Filtrationfiltered
10. 10
    SonstigeThe collected solid was dried in air

Vorschrift

A mixture of 3-bromo-4-chloropyridine (5 g, 0.026 mol) and hydrazine hydrate (80% in water, 80 mL) in dioxane (100 mL) was stirred at 100° C. overnight. After cooling down to RT, the mixture was concentrated. The residue was partitioned between 300 mL of EA and 300 mL of aq. sat. NH4Cl. The organic layer was washed with brine, dried over Na2SO4, filtered and concentrated to get crude product which was suspended in 30 mL of cold isopropyl alcohol and filtered. The collected solid was dried in air to get 4.2 g (87%) of 3-bromo-4-hydrazinylpyridine as a white solid. 1H NMR (400 MHz, DMSO-d6) δ 8.18 (s, 1H), 8.07 (d, J=5.6 Hz, 1H), 7.37 (s, 1H), 7.01 (d, J=5.6 Hz, 1H), 4.36 (s, 2H).

Quelle