Water → (S)-2-Methyl-piperidine-1-carboxylic acid N'-(5-fluoro-pyridin-2-yl)-hydrazide

Participants

Reaction Steps

To a solution of (5-fluoro-pyridin-2-yl)-hydrazine (582 mg, 4.58 mmol) and DIPEA (0.997 mL, 5.72 mmol) in dry DCM (20 mL) was added Intermediate 81a (740 mg, 4.58 mmol) and the resulting red solution stirred at RT for 66 h, and at reflux for 4 h. To the cooled solution was added water (20 mL) and the mixture shaken. The aqueous was extracted with DCM (20 mL), then the combined organics passed through a hydrophobic frit and concentrated in vacuo to leave a pale brown solid. FCC, using 0-5% MeOH in DCM, gave the title compound as a pale yellow solid (657 mg, 57%). 1H NMR (300 MHz, CDCl3): 1.22 (3H, d, J 6.9), 1.40-1.77 (6H, m), 2.96 (1H, td, J 13.0, 2.9), 3.85 (1H, ddd, J 13.3, 4.5, 2.2), 4.31 (1H, m), 6.50 (1H, s), 6.59 (1H, br s), 6.75 (1H, ddd, J 9.0, 3.6, 0.7), 7.27 (1H, ddd, J 9.1, 8.1, 3.1), 8.02 (1H, d, J 2.9).

Provenance & Evidence