Palladium-catalyzed cross-coupling reactions between benzyl, aryl, or allyl bromides and conjugated ene-yne-ketones lead to the formation of 2-alkenyl-substituted furans. This novel coupling reaction involves oxidative addition, alkyne activation-cyclization, palladium carbene migratory insertion, β-hydride elimination, and catalyst regeneration. Palladium (2-furyl)carbene is proposed as the key intermediate, which is supported by DFT calculations. The palladium carbene character of the key intermediate is validated by three aspects, including bond lengths, Wiberg bond order indices, and molecular orbitals, by comparison to those reported for stable palladium carbene species. Computational studies also revealed that the rate-limiting step is ene-yne-ketone cyclization, which leads to the formation of the palladium (2-furyl)carbene, while the subsequent carbene migratory insertion is a facile process with a low energy barrier (<5 kcal/mol).

ADF5 promotes stomatal closure by regulating actin filament dynamics, and members of the ABF/AREB transcription factor family may serve as potential upstream regulators of ADF5 in the drought stress/ABA signaling pathway.

Copper-catalyzed cross-coupling of N-tosylhydrazones with N-iminopyridinium ylides leads to the direct C-H alkylation. This direct C-H bond alkylation transformation uses inexpensive CuI as the catalyst without any ligand. The reaction is operationally simple and conducted under mild conditions, giving the corresponding alkylated pyridines in moderate to good yields. DFT calculation provides insights into the reaction mechanism, suggesting that the reaction proceeds through the Cu carbene migratory insertion process.

A transition-metal-free strategy to construct C(sp(2))-N bonds using arylboroxines and O-benzoyl hydroxylamines as coupling partners has been developed. This transformation provides a useful method to access various aromatic amines.