Phosphorus oxychloride → HCID 86735321, compound

Participants

Reaction Steps

13.4 g. of 6-hydroxy-2,5-dimethylpyrazolo[1,5-a]pyrido[3,2-e]pyrimidine-7-carboxylic acid, ethyl ester (0.05 mol.) and 100 ml. of phosphorous oxychloride are refluxed with stirring for 5 hours. The excess of chlorinating agent is distilled off and the dark residue is poured into ice-water. 6-Chloro-2,5-dimethylpyrazolo[1,5-a]pyrido[3,2-e]pyrimidine-7-carboxylic acid, ethyl ester precipitates, yield 6.4 g. (42%), m.p. 143°-145° (ethyl acetate).

Provenance & Evidence