A transient and recyclable C−H iodination has been designed for the synthesis of isoflavonoids through the domino reactions of o‐hydroxyphenyl enaminones and aryl boronic acids in the presence of catalytic KI and Pd catalyst. Instead of the conventional cross‐coupling strategy employing pre‐halogenated substrates, this method transforms raw C−H bond by means of a transient C−H halogenation to smoothly relay the subsequent C‐arylation. Consequently, such a method avoids the pre‐functionalization for C−halogen bond installation as well as the generation of stoichiometric halogen‐containing waste following the cross‐coupled product, disclosing an intriguing new coupling protocol to forge the C−C bond in the virgin area between classical C−X (X=halogen) bond cross coupling and the C−H activation.

The synthesis of useful 2-acyl benzoxazoles has been realized via the tandem methylene C-H oxygenation and oxazole annulation of N-(o-hydroxyphenyl)phenylacetamides via copper catalysis in one-pot fashion. Besides featuring the incomparable step-economy resulting from the multi-step transformation, the tunable synthesis of diverse 2-methylene functionalized benzoxazoles using identical starting materials as well as the expanded synthesis of corresponding benzothiazoles is also attractive advantage of the work.

The cheap and easily available o-aminophenols (OAPs) have been identified as practical directing component for the Pd-catalyzed aromatic γ-CÀ H bond arylation of phenylacetamides. Notably, the selective single and double arylation of the CÀ H bond(s) in the γ-potion has been independently realized by simply modifying reaction conditions. The catalytic system of Pd(CF 3 OO) 2 /K 2 S 2 O 8 /K 2 CO 3 enables the selective single CÀ H arylation. On the other hand, the catalysis of Pd(OAc) 2 in the presence of KIO 3 /K 2 CO 3 induces the selective arylation of both γ-CÀ H bonds.