The first example of carboxy group assisted, remote‐selective C(sp2)−H activation with a PdII catalyst has been developed and proceeds through a possible κ2 coordination of the carboxy group, thus suppressing the ortho‐C−H activation through κ1 coordination. Besides meta‐C−H olefination, direct meta‐arylation of hydrocinnamic acid derivatives with low‐cost aryl iodides has been achieved for the first time. These findings may motivate the exploration of novel reactivities of the carboxy assisted C−H activation reactions with intriguing selectivities.

N-Pyridylation of various N-heteroarenes, including N-heteroarene-containing peptides, was achieved using N-propargyl enaminones (isolated or generated in situ from propargyl amine and propynones) as masked polysubstituted pyridine cores. This metal-free procedure proceeds under mild reaction conditions and generates 1 equiv of H2O as the sole byproduct.

A TfOH-promoted tandem synthesis of 1,3-disubstituted naphthalenes is developed via a directed-aldol reaction and a Friedel–Crafts reaction. Two new C–C bonds and one new benzene ring are created efficiently in one pot due to the discovery of a TfOH-promoted highly chemoselective directed-aldol reaction between two different ketones with α-hydrogens.

An efficient cascade reaction via trapping in situ generated active intermediate 1,4-oxazepine, formed from base-promoted 7-exo-dig cyclization reaction of N-propargyl enaminone, has been developed. Alcohols/thiols and aldehydes were used as trapping agents, providing 2-alkoxy/2-sulfenylpyridines and dihydrofuro[2,3-b]pyridines in moderate to high yields. This cascade reaction was completed within 30 min at room temperature, generating 1 equiv of HO as the sole byproduct.

A novel approach to trisubstituted oxazoles has been developed that is based upon an iodine-mediated aerobic oxidative cyclization of enaminone derivatives. This transition-metal-free procedure was highly efficient and involved the removal of four hydrogen atoms under mild conditions.