Reaktion #470110

Reaktionsgleichung

hydrazoic acid

1,4-dichlorophthalazine

triethylamine

→

phthalazine

Ausbeute 15.1%

Lösungsmittel

xylene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas heated
2. 2
   Temperaturat reflux under nitrogen for 20.5 h
3. 3
   Sonstigethe solvent evaporated in vacuo
4. 4
   Sonstigethe residue partitioned between dichloromethane and water
5. 5
   SonstigeThe aqueous was separated
6. 6
   Extraktionre-extracted with dichloromethane (×2)
7. 7
   TrocknenThe combined extracts were dried (MgSO4)
8. 8
   Sonstigeevaporated in vacuo
9. 9
   Sonstigethe residue chromatographed on silica gel eluting with ethyl acetate

Vorschrift

A mixture of the preceding hydrazoic acid (798 mg, 3.91 mmol), 1,4-dichlorophthalazine (778 mg, 3.91 mmol) and triethylamine (0.54 ml, 3.9 mmol) in xylene (28 ml) was heated at reflux under nitrogen for 20.5 h. The mixture was cooled to room temperature, the solvent evaporated in vacuo and the residue partitioned between dichloromethane and water. The aqueous was separated and re-extracted with dichloromethane (×2). The combined extracts were dried (MgSO4), evaporated in vacuo and the residue chromatographed on silica gel eluting with ethyl acetate, then 5% methanol/dichloromethane to afford the title-phthalazine (77 mg, 6%), 1H NMR (360 MHz, CDCl3/d6-DMSO) δ 7.51 (1H, m, Ar—H), 7.55 (1H, s, Ar—H), 7.99 (1H, m, Ar—H), 8.11 (1H, m, Ar—H), 8.24 (1H, m, Ar—H), 8.38 (1H, d, J=7.8 Hz, Ar—H), 8.78 (1H, m, Ar—H), 8.83 (1H, m, Ar—H), 9.18 (1H, br s, Ar—H); MS (ES+) m/e 349 [MH]+.

Quelle