Reaktion #5338

Reaktionsgleichung

crude crystals

Methyl 2-ethoxy-1-[[2'-(ethoxycarbonyloxy-carbamimidoyl)biphenyl-4-yl]methyl]benzimidazole-7-carboxylate

1,8-diazabicyclo[5.4.0]undec-7-ene

→

title compound

Ausbeute 57.6%

Methyl 2-ethoxy-1-[[2'-(2,5-dihydro-5-oxo-1,2,4-oxadiazol-3-yl)biphenyl-4-yl]methyl]benzimidazole-7-carboxylate

Ausbeute 57.6%

Lösungsmittel

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe reaction mixture was partitioned between ethyl acetate (50 ml) and 1N HCl (20 ml)
2. 2
   WaschenThe organic layer was washed with water
3. 3
   Sonstigedried
4. 4
   Einengenconcentrated to dryness
5. 5
   SonstigeThe residue was crystallized from chloroformethyl acetate

Vorschrift

The crude crystals (4.0 g) obtained in Example (57b) was dissolved in ethyl acetate (50 ml). To the solution was added 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU, 3.2 g), and the mixture was stirred for 2 hours at 80° C. The reaction mixture was partitioned between ethyl acetate (50 ml) and 1N HCl (20 ml). The organic layer was washed with water, dried and concentrated to dryness. The residue was crystallized from chloroformethyl acetate to afford the title compound as colorless prisms (2.1 g, 45%), which was in agreement with that obtained in Example (1d).

Quelle