Example 15 Synthesis of 2-(1H-pyrazol-3-yl)pyridine (17a): compound 16a (1 g, 6.2 mmol) was dissolved with hydrazine hydrate (2 mL) in ethanol (3.3 mL) and reacted at 60°C for 0.5 hrs. Upon completion of the reaction, the mixture was cooled to room temperature and the solvent was subsequently removed under vacuum to afford the pale yellow solid product 17a (874.7 mg) in 97.3% yield.1H-NMR (400 MHz, CDCl3): δ 8.66 (d, J = 4.8 Hz, 1H), 7.75 (d, J = 3.6 Hz, 2H), 7.67 (d, J = 2Hz, 1H), 7.23-7.27 (m, 1H), 6.81 (d, J = 2Hz, 1H).
