The palladium-catalysed arylation/vinylation of α-methylene-γ-butyrolactone (1) proceeds in good yield, mainly to give stereodefined aryl/vinyl-substituted α-alkylidene-γ-butyrolactones 4. In addition, the palladium-catalysed arylation of α-methylene-γ-butyrolactone (1) may be directed towards the synthesis of 3-benzylfuran-2(5H)-ones 3 when the starting aryl iodides contain groups with electron-withdrawing conjugative properties. The combined palladium-catalysed coupling/hydrogenation reactions represent a new, simple route to functionalised 3-alkyl-γ-butyrolactones 5, giving prominence to the possibility of stereocontrol in the formation of the new stereocentres.
Palladium-Catalysed Vinylic Substitution of Aryl/Vinyl Iodides and Triflates with alfa-Methylene-gamma-butyrolactone – An Application to the Synthesis of 3-Alkyl-gamma-Butyrolactones through Combined Palladium-Catalysed Coupling/Hydrogenation Reactions
CHIARINI, MARCO;
2001-01-01
Abstract
The palladium-catalysed arylation/vinylation of α-methylene-γ-butyrolactone (1) proceeds in good yield, mainly to give stereodefined aryl/vinyl-substituted α-alkylidene-γ-butyrolactones 4. In addition, the palladium-catalysed arylation of α-methylene-γ-butyrolactone (1) may be directed towards the synthesis of 3-benzylfuran-2(5H)-ones 3 when the starting aryl iodides contain groups with electron-withdrawing conjugative properties. The combined palladium-catalysed coupling/hydrogenation reactions represent a new, simple route to functionalised 3-alkyl-γ-butyrolactones 5, giving prominence to the possibility of stereocontrol in the formation of the new stereocentres.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
