Synthesis of new 4-(1-ethylthio-2,2,2-trifluoroethyl)-6-methylpyridazin-3(2H)-ones starting from S-ethyl 4-oxo-2-(pentafluoroethyl)pentanethiolate and hydrazines

Vasile Dinoiu (1, 2) , Bernard Tinant (3) , Jean-Marc Nuzillard (4) , J.-P. Bouillon (1)

1 SMS - Sciences et Méthodes Séparatives
2 ROMANIAN ACADEMY - Institute of Organic Chemistry, C.D. Nenitzescu
3 UCL - Université Catholique de Louvain = Catholic University of Louvain
4 Laboratoire de Pharmacognosie

The paper presents a one-pot conversion of γ-keto-α-pentafluoroethyl thioester into new pyridazin-3-ones and α,β-unsaturated lactams. The structures of all new compounds were ascribed using 1D (19F, 1H, 13C) and 2D (1H–15N) NMR data, and X-ray diffraction analysis. Two possible competitive reaction mechanisms for the synthesis of pyridazin-3-ones and lactams are presented.

Keywords: Trifluoromethyl; γ-Ketothioester; Furan; Lactam; Pyridazinone

Domains: Chemical Sciences; Chemical Sciences; Organic chemistry; Chemical Sciences; Material chemistry

Vasile Dinoiu, Bernard Tinant, Jean-Marc Nuzillard, J.-P. Bouillon. Synthesis of new 4-(1-ethylthio-2,2,2-trifluoroethyl)-6-methylpyridazin-3(2H)-ones starting from S-ethyl 4-oxo-2-(pentafluoroethyl)pentanethiolate and hydrazines. Journal of Fluorine Chemistry, 2006, 127 (1), pp.101 - 107. ⟨10.1016/j.jfluchem.2005.11.001⟩. ⟨hal-01935486⟩