5-Methyl-pyrazolo[1,5-a]pyridine-3-carboxylic acid ethyl ester

13061-96-6

885276-93-7

51135-70-7

Ethyl 5-bromopyrazolo[1,5-a]pyridine-3-carboxylate (1.0 g, 3.73 mmol) and methylboronic acid (448 mg, 7.46 mmol) were used as raw materials, and Pd(dppf)Cl2 (545 mg, 0.746 mmol) and Cs2CO3 (2.42 g, 7.46 mmol) were added, protected by argon gas, in DMF ( 5.0 mL) in DMF. The reaction mixture was stirred at 100 °C for 2 hours. After completion of the reaction, the mixture was concentrated and purified by silica gel column chromatography using petroleum ether: ethyl acetate (5:1, v/v) as eluent to afford the target compound, ethyl 5-methylpyrazolo[1,5-a]pyridine-3-carboxylate, as an orange solid (589 mg, 77% yield).ESI-MS m/z = 204.5 [M + H]+.