反应详情

A mixture of NH2OH.HCl (229 mg, 3.3 mmol) and 4-(3-formyl-1H-indazol-5-yl)-1,4-dihydro-2,6-dimethyl-3,5-pyridinedicarbonitrile (200 mg, 0.66 mmol), from Synthetic Example 10B, in pyridine (5 mL) was stirred at rt overnight. After removal of pyridine under vacuum, the residue was treated with a saturated solution of NaHCO3 and extracted with CH2Cl2. The organic phases were combined, washed with brine, and concentrated. The residue was purified by column to give 1,4-dihydro-4-[3-[(E)-(hydroxyimino)methyl]-1H-indazol-5-yl]-2,6-dimethyl-3,5-pyridinedicarbonitrile (143 mg, 68%) as a powder (Cpd. No. 149, Table 2). 1H-NMR (400 MHz, DMSO-D6): δ=11.42 (s, 1H), 9.55 (s, 1H), 8.36 (s, 1H), 7.85 (s, 1H), 7.60 (d, 1H), 7.38 (d, 1H), 4.58 (s, 1H), 2.03 (s, 6H) ppm.

1. customAfter removal of pyridine under vacuum
2. additionthe residue was treated with a saturated solution of NaHCO3
3. extractionextracted with CH2Cl2
4. washwashed with brine
5. concentrationconcentrated
6. customThe residue was purified by column