反应详情

To a solution of (2Z)-3-hydroxy-1-(4-pyridinyl)-2-buten-1-one (8 g, crude, 49 mmol) and cyanoacetamide (4.12 g, 49 mmol) in anhydrous EtOH (100 mL) was added piperidine (4.17 g, 49 mmol) under N2 at 75° C. The mixture was heated at reflux for 1 h, and then cooled to room temperature. After filtration, the solid was collected and washed with H2O to give the crude product (4 g) as two isomers. After separation by HPLC, 1.8 g of 6-methyl-2-oxo-1,2-dihydro-4,4′-bipyridine-3-carbonitrile and 1.2 g of 4-methyl-6-oxo-1,6-dihydro-2,4′-bipyridine-5-carbonitrile were obtained. The identity of 6-methyl-2-oxo-1,2-dihydro-4,4′-bipyridine-3-carbonitrile was established by nOE analysis. 1H NMR (400 MHz, DMSO-d6) δ 12.79 (br. s., 1H), 8.75 (d, 2H), 7.58 (d, 2H), 6.37 (s, 1H), 2.31 (s, 3H).

1. temperatureThe mixture was heated
2. temperatureat reflux for 1 h
3. filtrationAfter filtration
4. customthe solid was collected
5. washwashed with H2O
6. customto give the crude product (4 g) as two isomers
7. customAfter separation by HPLC, 1.8 g of 6-methyl-2-oxo-1,2-dihydro-4,4′-bipyridine-3-carbonitrile