Table 2. Effect of Solvents on Synthesis of Pyrazole-4-Carbonitrile Derivatives 4a–o.
solventb | time (min) | yield (%)a |
---|---|---|
DCM | 120 | 40 |
DMF | 120 | 47 |
THF | 120 | 53 |
CH3CN | 120 | 42 |
CHCl3 | 120 | 49 |
MeOH | 40 | 76 |
ACOH | 40 | 75 |
EtOH | 15 | 92 |
H2O | 15 | 97 |
Isolated yields based on 4a.
Reaction conditions: 1a (1 mmol), 2 (1 mmol), 3 (1 mmol), and catalyst (0.1 mmol) in water were heated at 80 °C under ultrasonic irradiation condition for 15 min.