Reacción #1340632

Ecuación de reacción

HCl

methyl[(4Z)-1-methyl-5-oxo-4-{1-[(pyridin-2-ylmethyl)amino]pentylidene}-4,5-dihydro-1H-pyrazol-3-yl]acetate

sodium

→

pure product

Rendimiento 80.0%

4-butyl-2-methyl-5-(pyridin-2-ylmethyl)-1H-pyrazolo[4,3-c]pyridine-3,6(2H,5H)-dione

Rendimiento 80.0%

Disolventes

i-PrOH

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaThe reaction mixture was refluxed for 1 h
2. 2
   Temperaturacooled
3. 3
   Otro50 ml of i-PrOH were removed in vacuo and 25 ml of H2O
4. 4
   workup.ADDITIONwere added
5. 5
   Otroin the fridge overnight
6. 6
   OtroThe white precipitate formed
7. 7
   Filtraciónwas filtered off
8. 8
   Lavadowashed with water (2×5 ml)
9. 9
   Secadowith cyclohexane and dried in vacuo

Procedimiento

An isopropanolic solution of i-PrONa, obtained by dissolving of sodium (0.082 g, 3.57 mmol, 1 equiv.) in i-PrOH (75 ml), was treated with methyl[(4Z)-1-methyl-5-oxo-4-{1-[(pyridin-2-ylmethyl)amino]pentylidene}-4,5-dihydro-1H-pyrazol-3-yl]acetate (Compound of Formula (VIII) (0.61 g, 3.57 mmol, 1 equiv.). The reaction mixture was refluxed for 1 h, then cooled and neutralized to pH 7 by addition of 0.59 ml of a 20% aqueous HCl solution. 50 ml of i-PrOH were removed in vacuo and 25 ml of H2O were added before placing the flask in the fridge overnight. The white precipitate formed was filtered off, washed with water (2×5 ml), then with cyclohexane and dried in vacuo. 0.88 g of pure product 4-butyl-2-methyl-5-(pyridin-2-ylmethyl)-1H-pyrazolo[4,3-c]pyridine-3,6(2H,5H)-dione was obtained. Yield 80%. 1HNMR (DMSO-d6, 400 MHz): 0.80 (3H, t, J=7.2 Hz); 1.29-1.35 (2H, m); 1.38-1.43 (2H, m); 3.19 (3H, s); 3.22-3.24 (2H, m); 5.49 (2H, s); 5.72 (1H, s); 7.42 (1H, d, J=8 Hz); 7.62 (1H, t, J=6.6 Hz); 8.12 (1H, t, J=8 Hz); 8.65 (1H, d, J=5.2 Hz). MS (ESI+): 313.4; MS (ESI−): 311.3.

Fuente