| abstract |
The present invention relates to a process for the preparation of 4,5-dihydropyridazin-3 (2H) -one derivatives of formula (I) wherein R1 is hydrogen, C3-6cycloalkyl, C1-6alkyl, optionally substituted with a nitro group. phenyl or -CH 2 -R 0 wherein R 0 is phenylcarbonyl, furyl, indolyl or thienyl, or optionally halogen, C 1-4 alkyl, hydroxy, C 1-4 alkoxy, 1 Phenyl substituted with C4-C4 alkylthio, trifluoromethyl, cyano, nitro, or C1-4alkylcarbonylamino; R 2 is C 1-6 alkyl, naphthyl, coumarin, thienyl or phenyl optionally substituted by halogen, phenyl, nitro, hydroxyl or C 1-4 alkoxy; X is O or S; EN 225 528 Β1 The scope of the description is 14 pages (including 2 sheets) |