Iridium(III)-Catalyzed Approach for the Synthesis of Fused Arenes: Access to Isoindolines, Indanes, and Dihydroisobenzofurans

A facile and efficient method for the synthesis of isoindoline, indane, and dihydroisobenzofuran derivatives has been developed through the application of a halogen-bridged iridium(III) complex to the [2+2+2] cycloaddition of ,-diynes with alkynes. The cycloaddition tolerates a broad range of substitution groups, such as alcohol, alkyl, ether, and halogen, and the chemistry can be extended to prepare the corresponding borylated fused arenes. The reaction shows that hindered starting materials are also good partners, which provide the desired fused arenes in good yields.