2-Hydrazinoethanol → 1H-Pyrazolo(3,4-b)pyridine-1-ethanol, 3-(3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl)-

Participants

Reaction Conditions

Reaction Steps

A solution of 45.2 g of 4-(2-chloronicotinoyl)2,6-di-tertiary butylphenol and 21 g of 2-hydrazinoethanol in 230 ml of pyridine is refluxed under stirring for 18 hours. After completion of the reaction, the pyridine is concentrated and 140 ml of ethanol and 70 ml of water are added to the residue. The mixture is warmed to dissolve and then cooled to 0° C. The precipitated crystals are collected by filtration, recrystallized from 70% dioxane and then dried to give 40 g of 3-(3,5-di-tertiary butyl-4-hydroxyphenyl)-1-(2-hydroxyethyl)-1H-pyrazolo[3,4-b]pyridine, melting at 135°-137° C.

Provenance & Evidence