Реакция #5338

Уравнение реакции

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

Выход 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

Выход 57.6%

Растворители

ethyl acetate

Условия реакции

Обработка

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

Методика

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).

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