Pyridazines. Part 30:Palladium-Catalysed Synthesis of 5-Substituted 6-Phenyl-3(2<i>H</i>)-pyridazinones Asissted by a Retro-Ene Transformation
作者:Eddy Sotelo、Alberto Coelho、Enrique Raviña
DOI:10.1055/s-2002-35567
日期:——
The efficient one-pot functionalization, through palladium-catalysed reactions, of position 5 of the 6-phenyl-3(2H)-pyridazinonesystem has been performed using a retro-ene-assisted fragmentation. This route allows accessthrough a short synthetic sequence to several pharmacologically useful 3(2H)-pyridazinones.
Pyridazines. Part 35:Traceless Solid PhaseSynthesis of 4,5- and 5,6-Diaryl-3(2<i>H</i>)-pyridazinones
作者:Enrique Raviña、Eddy Sotelo
DOI:10.1055/s-2003-39882
日期:——
A new method for the traceless solid phase synthesis of 3(2H)-pyridazinones has been developed employing dihydropyran-functionalized resin. The procedure has permitted the preparation of several diarylpyridazinones through a Suzuki cross-coupling reaction and cleavage conditions that promoted a retro-ene fragmentation.
A convenient and efficient palladium-catalysed retro-ene-assisted method has been developed to prepare a series of 5-substituted-6-phenyl-3(2H)-pyridazinones as potential antiplatelet drugs. The most active compounds were those that contain a 3-phenyl-3-oxo-propenyl fragment or a phenylthio group at position 5 of the heterocyclic ring. (C) 2003 Elsevier Ltd. All rights reserved.