Palladium-catalyzed sequential reaction viaSonogashira coupling, isomerization, Claisen rearrangement and [4 + 2] cycloaddition sequence for the rapid synthesis of tricyclo[3.2.1.02,7]oct-3-ene derivatives

An interesting sequential reaction consisting of Sonogashira coupling, propargyl–allenyl isomerization, allenyl–benzyl Claisen rearrangement and [4 + 2] cycloaddition was developed. This reaction provides an efficient synthesis of fused tricyclo[3.2.1.02,7]oct-3-enes.