反应详情

Sodium ethoxide (3.10 g, 45.62 mmol) was added to a solution of 3-(2-cyano-acetylamino)-thiophene-2-carboxylic acid methyl ester (24) (3.10 g, 45.62 mmol) in anhydrous ethanol and refluxed overnight. The solution was cooled and excess solvent was distilled off. The residue was dissolved in water and acidified to pH 2 by cold diluted HCl solution. The solids formed were filtered, washed by cold water, and dried under vacuum at room temperature to yield 6.7 g (84%) of 7-hydroxy-5-oxo-4,5-dihydro-thieno[3,2-b]pyrdine-6-carbonitrile as white solids. MP>300° C.; 1H NMR (400 MHz, DMSO-d6) δ 6.96 (d, J=5.2 Hz, 1H), 8.04 (d, J=5.2 Hz, 1H), 12.10 (s, 1H) ppm; MS mz=193 amu(M++1).

1. temperaturerefluxed overnight
2. temperatureThe solution was cooled
3. distillationexcess solvent was distilled off
4. dissolutionThe residue was dissolved in water
5. customThe solids formed
6. filtrationwere filtered
7. washwashed by cold water
8. customdried under vacuum at room temperature