A novel route for ortho-selective C–H borylation of 2-phenylthiopyridines using BBr3 as the boron source under metal-free conditions has been reported. The reaction exhibited site exclusivity, and the synthesized aryl boronates were freely converted to various useful intermediates. Thus, this facile method would be beneficial to synthesize structurally diversified phenylthioethers derivatives and other materials containing boron-nitrogen coordination.

The direct arylation of aliphatic ketones has been developed via Pd-catalyzed β-C­(sp3)–H bond functionalization with 2-(aminooxy)-N,N-dimethylacetamide as a novel transient directing group (TDG), which showed remarkable directing ability to generate arylated products in moderate to good yields. Furthermore, the reaction can tolerate abundant substrate of ketones and aryl iodides. This study expands the scope of applications for TDGs.

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Palladium-catalyzed sequential C­(sp3)–H and C­(sp2)–H bond diolefination reaction of o-toluidine has been realized for the first time using acetyl-protected aminoethyl phenyl thioether ligands. This novel reaction allows for preparation of the conjugated diene structure via an immediate second olefination on the basis of the first C­(sp3)–H olefination in one pot. Various triflyl-protected anilines and acrylates were used as coupling partners elegantly. Furthermore, the unpurified diolefination products can be easily converted to tetrahydroquinoline derivatives.

A novel route to 3,4‐dihydropyrimido[1,6‐a]indol‐1(2H)‐one derivatives enabled by Rh(III)‐catalyzed cascade C−H activation/annulation of N‐carbamoylindoles with silyl enol ethers has been reported. The reaction features mild conditions, wide substrate scope, diverse functional group tolerance and moderate to good yields. Furthermore, a plausible reaction mechanism is confirmed by an available rhodacycle intermediate.