Potassium Hydroxide → HCID 21421717, compound

Participants

Reaction Steps

24.9 g. of 7-ethyl-4,7-dihydro-2-methyl-4-oxo-2H-pyrazolo[3,4-b]pyridine-5-carboxylic acid, ethyl ester (0.1 mol.) are treated with 10 g. of potassium hydroxide in 100 ml. of ethyl alcohol at reflux temperature for 12 hours with stirring. The solvent is removed in vacuo and the crystalline, residual potassium salt is dissolved in 100 ml. of water. After acidifying the solution with acetic acid, 7-ethyl-4,7-dihydro-2-methyl-4-oxo-2H-pyrazolo[3,4-b]pyridine-5-carboxylic acid crystallizes, yield 19 g. (68%); m.p. 273°-275° (DMF).

Provenance & Evidence