Hydrochloric Acid → HCID 46182771, compound

Participants

Reaction Steps

An isopropanolic solution of i-PrONa, obtained by dissolving of sodium (0.017 g, 0.713 mmol, 1 equiv) in i-PrOH (16 ml), was treated with methyl[(4E)-1-benzyl-5-oxo-4-{1-[(pyridin-2-ylmethyl)amino]ethylidene}-4,5-dihydro-1H-pyrazol-3-yl]acetate (Compound of Formula (VIII) (0.270 g, 0.713 mmol, 1 equiv.). The reaction mixture was refluxed for 1 h, then cooled and neutralized to pH 7 by addition of 0.12 ml of a 20% aqueous HCl solution. 15 ml of i-PrOH were removed in vacuo and 10 ml of H20 were added before placing the flask in the fridge overnight. The white precipitate formed was filtered off, washed with water (2×3 ml), then with cyclohexane and dried in vacuo. 0.240 g of pure product 2-benzyl-4-methyl-5-(pyridin-2-ylmethyl)-1H-pyrazolo[4,3-c]pyridine-3,6(2H,5H)-dione was obtained. Yield 97%. 1H NMR (500 MHz, DMSO-d6, ppm) 2.78 (s, 3H), 4.81 (s, 2H), 5.37 (s, 2H), 5.59 (s, 1H), 7.31-7.26 (m, 5H), 7.36 (m, 2H), 7.76 (td, J 7.6, 1.9 Hz, 1H), 8.46 (dt, J 4.2, 1.6 Hz, 1H), 10.34 (s, 1H); MS (ESI+)=347.2.

Provenance & Evidence