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The synthesis of indanone derivatives by the Rh(III)-catalyzed reaction of α-carbonyl sulfoxonium ylides with activated alkenes is reported. The reaction shows a high tolerance for functional groups and furnishes a variety of substituted indanone derivatives via a formal [4 + 1] cycloaddition. Highly stable sulfoxonium ylides were used as substrates in this C-H functionalization, and their bifunctional character could be effectively exploited using Rh(III) catalysis via sequential double C-C bond formation. Based on mechanistic studies including deuterium-labeling experiments, the reaction is proposed to proceed as follows: Rh(III)-catalyzed C-H oxidative alkenylation via β-hydride elimination, readdition of H-Rh species, a 1,2-carbon shift with the elimination of DMSO, and protonation.

The cobalt-catalyzed chelation-assisted C-H iodination of aromatic amides using molecular iodine as an iodinating reagent is reported. The reaction is carried out in an atmosphere of air and uses Co(OAc) 2 ·4H 2 O as an efficient catalyst and 4-chloro-2-(4,5-dihydrooxazol-2-yl)aniline as a directing group. The reaction shows a wide functional group tolerance. Mechanistic studies suggest that the reaction proceeds through a different mechanism from that of our previously reported transformation in which a Co(II) catalyst/8-amino-5-choloroquinoline chelation system was used.