Table 1 Synthesis of pyrazolopyridine derivatives 5a-k in optimal conditionsa.
Entry | R | Product | Yieldb (%) | Mp (°C) | |
|---|---|---|---|---|---|
Found | Reported | ||||
1 | C6H5 | 5a | 96 | 240–241 | 240–24227 |
2 | 3-NO2-C6H4 | 5b | 95 | 285–287 | 286–28837 |
3 | 4-NO2-C6H4 | 5c | 93 | 296–298 | 295–29727 |
4 | 4-CN-C6H4 | 5d | 93 | 286–288 | 286–28837 |
5 | 3-Br-C6H4 | 5e | 90 | 244–246 | 245–24736 |
6 | 4-Cl-C6H4 | 5f | 94 | 255–257 | 255–25727 |
7 | 4-F-C6H4 | 5g | 96 | 259–261 | 258–26038 |
8 | 4-OH | 5h | 90 | 268–270 | 269–27138 |
9 | 4-Me-C6H4 | 5i | 93 | 244–246 | 245–24738 |
10 | 2,4-(Cl)2-C6H3 | 5j | 91 | 308 | >30037 |
11 | pyrid-2-yl | 5k | 90 | 219–221 | 21836 |
