Process for the preparation of 1,2,4-triazine-3,5-diones

摘要

Prodn. of 2-aryl-1,2,4-triazine-3,5-diones (I) comprises heating a 2-aryl-6-carboxy-1,2,4-triazinone-3,5-dione (I) at 80-220 degrees C in an aprotic organic solvent with b.pt. 50-150 degrees C, opt. under pressure. Ar = opt. substd. aryl or heteroaryl.