A palladium catalyzed stereo-convergent aminocarbonylation of 1,3-dienes with nitroarenes: synthesis of (E,E)-dienamides†
Abstract
A palladium catalyzed stereo-convergent aminocarbonylation of 1,3-dienes with nitroarenes has been developed. This reaction proceeds in a highly stereo-convergent manner, wherein mixtures of E/Z isomers of 1,3-dienes reacted with nitroarenes and produced (E,E)-dienamides with high stereoselectivities. A broad range of (E,E)-dienamides were prepared in good to excellent yields from readily available starting materials. The reaction is speculated to proceed through the vinylogous addition of 1,3-dienes to isocyanatoarenes, which are in situ generated from the reaction of nitroarenes with Mo(CO)6 in the presence of the Pd(0) catalyst, using the Pd(0) complex as a π-Lewis base catalyst via η2 coordination to activate 1,3-dienes.