Reaktion #1622044

Reaktionsgleichung

compound

Ethyl chloro[2-(4-chlorophenyl)hydrazono]acetate

benzene

benzene

4-chlorostyrene

→

title compound

Ethyl 1,5-bis(4-chlorophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylate

Lösungsmittel

triethylamine

Reaktionsbedingungen

Aufarbeitung

1. 1
   FiltrationThe cooled mixture was filtered
2. 2
   Sonstigedried on the vacuum pump
3. 3
   Sonstigeto remove excess styrene
4. 4
   SonstigeThe residual solid was recrystallized from hexane/benzene (charcoal)

Vorschrift

The compound of Example 6 (5.0 gm) was heated in refluxing benzene (30 ml) containing 4-chlorostyrene (7.0 ml). Addition of a benzene (10 ml) solution of triethylamine(7.5 ml) was followed by one hour of continued heating. The cooled mixture was filtered, rotovapped, and dried on the vacuum pump to remove excess styrene. The residual solid was recrystallized from hexane/benzene (charcoal) to give the title compound (6.3 gm); m.p.: 128° to 130° C. NMR (CDCl3) 7.3-6.9 (m, 8H, ArH), 5.4 (dd, 1H, CH), 4.3 (q, 2H, OCH2), 3.8 (m, 1H, CH), 3.0 (m, 1H, CH), 1.38 (t, 3H, CH3).

Quelle