反应详情

To a solution of 1H-indazole-6-carbaldehyde (2.00 g, 13.7 mmol), K2CO3 (3.79 g, 27.4 mmol) in DMF (15 mL) was added dropwise a solution of I2 (5.91 g, 23.3 mmol) in DMF (15 mL) and the reaction allowed to stir for two h. An aqueous solution consisting of Na2S2O4 (3.30 g)/K2CO3 (0.20 g)/H2O (30 mL) was then added and the solution stirred for one h. The product was then precipitated by pouring the solution over ice-water (300 mL) and collected by vacuum filtration to give after drying 3.02 g, 81% of a beige powder. 1H NMR (400 MHz, CD3OD) δ 10.11 (s, 1H), 8.11 (s, 1H), 7.74 (d, J=8.34 Hz, 1H), 7.62 (d, J=8.34 Hz, 1H); MS ESI 272.9 [M+H]+, calcd for [CsH5IN2O+H]+ 272.95.

1. additionwas then added
2. stirringthe solution stirred for one h
3. customThe product was then precipitated
4. additionby pouring the solution over ice-water (300 mL)
5. filtrationcollected by vacuum filtration
6. customto give
7. dry with materialafter drying 3.02 g, 81% of a beige powder