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A silver‐catalyzed protocol for the synthesis of 3‐(1H‐isochromen)‐chromones is described. The method involves an initial 6‐endo‐dig cyclization of o‐alkynylbenzaldehydes and domino C−H alkylation and chromone annulation of the o‐hydroxyarylenaminones, which enables the installation of 1H‐isochromen and chromone in a single structure. This synthetic strategy is advantageous for the excellent regioselectivity, step economy, concise one‐pot methodology, gram‐scale synthesis, as well as high bond‐forming efficiency. [ABSTRACT FROM AUTHOR]

The C(sp2)−H phosphorothiolation involving cyclization process through a transition‐metal‐free strategy is reported. It provides an attractive approach for the construction valuable S‐3‐chromon phosphorothioates from o‐hydroxyarylenaminones and P(O)SH compounds in the presence of 1.0 equiv. of iodine at 60 °C. This novel protocol shows readily available chemicals, broad substrate scope, and mild reaction conditions. [ABSTRACT FROM AUTHOR]

Copper(II)‐mediated unprecedented intermolecular radical [3+2] annulation of N,N‐dimethyl enaminones has been developed. The protocol is promoted simply by copper(II) chloride to access 5‐acyl‐3‐furancarboxaldehydes with acceptable to good yields and broad substrate scope. This reaction allows the formation of multiple new bonds, including C(sp2)−O bond between two nucleophilic sites, C(sp2)−C(sp2) bond and C=O bond, through a radical cyclization process. Moreover, gram‐synthesis and application research show the potential application value of this transformation in industry. [ABSTRACT FROM AUTHOR]