Thionyl Chloride → HCID 178463031, compound

Participants

Reaction Steps

31.3 g. of 1-ethyl-6-hydroxy-1H-pyrazolo[3,4-b]-pyrazine-5-carboxylic acid (0.15 mol.) are carefully added in portions to 300 ml. of thionyl chloride. As soon as the gas evolution has ceased, the mixture is heated at reflux for 3 hours. After removal of excess thionyl chloride under vacuum, the residue is dissolved in benzene. Evaporation of the benzene provides 30.5 g. (90%) of amorphous 1-ethyl-6-hydroxy-1H-pyrazolo[3,4-b]pyrazine-5-carbonyl chloride which is used without further purification.

Provenance & Evidence