PROCESS FOR THE PREPARATION OF PYRIDAZINE-3-ON DERIVATIVES, INTERMEDIATES AND PREPARATION OF THE LATTER

摘要

~a-Trifluoromethyl, ~a-hydroxy, ~b-hydrazone carboxylic acid derivatives of formula (I) and their salts with alkali(ne earth) metals or an amine are new. R2, R3 = H or 1-3C alkyl; and Q = optionally substituted Ph. Also claimed is a process for producing a pyridazin-3-one derivative of formula (VII) comprising ring closure of (I) at 80-250 deg C.