A chemo-selective Rh(II)/Pd(0) dual catalysis that promotes one-pot synthesis of C3quaternary allylic oxindoles from N-aryl-a-diazo-bketoamides and functionalized allyl carbonates in good to excellent yields has been developed. The efficiency of this transformation relies on the choice of Rh(II)/Pd(0) dual catalysis strategy that enabled cascade intramolecular aryl CÀH insertion and allylic alkylation under mild conditions.

A synthesis of 4‐substituted chroman‐3‐one derivatives has been developed through a gold(III) catalyzed oxidation‐cyclization of ynones in good to excellent yield using easily prepared substrates. A broad range of synthetically useful functional groups (halide, alkene, alkyne, phenolic hydroxyl) were tolerated. Further application of this method paves a new way to prepare the skeleton of oblarotenoids. A cascade oxidative cyclization for construction of pyrano[2,3‐c]chromen‐1(5H)‐one derivatives is also presented.magnified image

A Rh(II)-catalyzed oxy-alkynylation of acceptor–acceptor carbenes using EBX reagents was successfully developed. The key alkyne-transfer step is likely to occur through a tandem process involving a β-addition, an α-elimination, and a 1,2-shift, which was supported by the formation of alkylidene carbene. Various diverse C2-quaternary alkyne-substituted benzofuran-3-ones and 2,2,4,5-tetrasubstituted 3(2H)-furanones can be synthesized smoothly, depending on the choice of diazo compounds and the base additives. Furthermore, this reaction is characterized by mild conditions, high functional group compatibility, and a broad substrate scope.