Palladium-catalyzed ring expansion of vinyl oxaspirohexanes

Article abstract of DOI:10.1016/S0040-4039(00)92716-3

Pd(0)-catalyzed ring expansion of vinyl oxaspirohexanes occurred smoothly in the presence of 1 equiv of p-nitrophenol in tetrahydrofuran, yielding initially 2-vinylcyclopentanones in high yields. However, vinyl oxaspiroheptanes failed to undergo ring expansion under the present conditions.