反应详情

In 80 mL of tetrahydrofuran was dissolved 4.0 g of 3-amino-6-bromo-2-pyrazinecarbonitrile synthesized according to the procedure mentioned in U.S. Pat. No. 3,341,540. While cooling the solution with ice, 1.2 g of 60% sodium hydride and 2.8 mL of benzoyl chloride were successively added, and further 0.8 g of 60% sodium hydride was added. The mixture thus obtained was stirred at an ice-cooled temperature for one hour and thereafter at room temperature for 30 minutes. Then, 0.4 g of 60% sodium hydride was added additionally, and the mixture thus formed was stirred at room temperature for 30 minutes. After cooling the reaction mixture with ice, the mixture was poured into a liquid mixture consisting of 50 mL of ethyl acetate and 100 mL of water, and pH was adjusted to 5 with 6 mol/L hydrochloric acid. The deposited matter was collected by filtration, and the residue thus obtained was dissolved in a mixture of 50 mL of ethyl acetate and 100 mL of tetrahydrofuran, treated with active charcoal, and filtered, after which the solvent was removed under reduced pressure. The residue thus obtained was washed with diisopropyl ether to obtain 1.7 g of N-(5-bromo-3-cyano-2-pyrazinyl)-benzamide as a light yellow-colored solid product. Furthermore, organic layer was separated from the filtrate obtained above, and organic layer was washed successively with water and saturated aqueous solution of sodium chloride, treated with active charcoal and dried on anhydrous magnesium sulfate, and the solvent was removed under reduced pressure. The residue thus obtained was washed with diisopropyl ether to obtain 2.9 g of N-(5-bromo-3-cyano-2-pyrazinyl)-benzamide as a yellow-colored solid product.

1. customsynthesized
2. additionwere successively added
3. customThe mixture thus obtained
4. temperaturecooled temperature for one hour
5. customthe mixture thus formed
6. temperatureAfter cooling the reaction mixture with ice
7. additionthe mixture was poured into a liquid mixture
8. filtrationThe deposited matter was collected by filtration
9. customthe residue thus obtained
10. filtrationfiltered
11. customafter which the solvent was removed under reduced pressure
12. customThe residue thus obtained
13. washwas washed with diisopropyl ether