Reaktion #1716264

Reaktionsgleichung

8-bromo-4-[1-dimethylamino-meth-(E)-ylidene]-3,4-dihydro-2H-benzo[b]-oxepin-5-one

hydrazine dihydrochloride

→

8-Bromo-4,5-dihydro-2H-6-oxa-1,2-diaza-benzo[e]azulene

Ausbeute 90.2%

Lösungsmittel

water

isopropyl alcohol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturbefore cooling to room temperature
2. 2
   EinengenThe reaction mixture was concentrated in vacuo
3. 3
   Sonstigeto remove the volatile solvent
4. 4
   FiltrationThe resulting suspension was filtered
5. 5
   Waschenthe filtrate washed with water
6. 6
   Sonstigedried under vacuum at 40° C.

Vorschrift

To a suspension of 8-bromo-4-[1-dimethylamino-meth-(E)-ylidene]-3,4-dihydro-2H-benzo[b]-oxepin-5-one (5.32 g, 17.9 mmol) in isopropyl alcohol (50 mL) was added powdered hydrazine dihydrochloride (3.77 g, 35.9 mmol) at room temperature, then the mixture stirred for 2 h. The reaction mixture was diluted with water (20 mL) and then heated at 100° C. for 2 h before cooling to room temperature. The reaction mixture was concentrated in vacuo to remove the volatile solvent. The resulting suspension was filtered and the filtrate washed with water and dried under vacuum at 40° C. to yield 8-Bromo-4,5-dihydro-2H-6-oxa-1,2-diaza-benzo[e]azulene as a pale yellow solid (4.28 g, 90%). 1H NMR δ (ppm)(DMSO-d): 8.07 (1 H, d, J=8.52 Hz), 7.64 (1 H, s), 7.30-7.24 (1 H, m), 7.21 (1 H, d, J=2.07 Hz), 4.24 (2 H, dd, J=5.63, 4.50 Hz), 3.00 (2 H, t, J=5.09 Hz).

Quelle