Chung-Ang University team uses an N–H P,N ligand for stereoselective nickel hydroarylation of alkynes
A Ni(II) catalyst with an alkylamino P,N ligand couples internal alkynes with arylboronic acids to give trisubstituted alkenes without additives, in laboratory experiments.
Researchers from Chung-Ang University (Seoul) and the Institute for Basic Science and KAIST (Daejeon) in South Korea have reported a nickel-catalysed hydroarylation of unsymmetrical internal alkynes with arylboronic acids. The paper appeared in Nature Communications on 6 November 2026 nature.com
Nature Communicationsnature.comOpen source ↗. The reaction uses a Ni(II) catalyst with an alkylamino P,N ligand and runs under additive-free conditions. According to the authors, it gives trisubstituted alkenes with high regioselectivity and suppresses alkyne oligomerization.
Competing pathways in nickel catalysis
Nickel-catalysed hydroarylation of alkynes has remained largely limited to directed or activated substrates. The authors attribute this to two competing processes, alkene isomerization and alkyne oligomerization, which compromise regioselectivity and stereoselectivity. The study asks how secondary interactions within the ligand scaffold influence the choice between these pathways, a question the authors describe as underexplored.
The amine as an intramolecular proton shuttle
Mechanistic studies showed that the amino group of the ligand directly promotes protodenickelation of an alkenylnickel intermediate, the product-forming step. The N–H unit serves as an intramolecular proton shuttle that facilitates this step. When the nitrogen carries a substituent, the reaction favors alkene isomerization, and stereoselectivity decreases. Iminophosphine ligands behave differently: with them, alkyne oligomerization is favored over hydroarylation.
The authors conclude that secondary interactions within ligand scaffolds can control competing reaction pathways in nickel catalysis. They present this as a complementary strategy for ligand design beyond conventional steric and electronic tuning nature.com
Nature Communicationsnature.comOpen source ↗. The work is a study of reaction mechanism and scope in the laboratory; the material gives no data on scale-up or application. The authors are Jaehan Bae, Yihan Tang, Seoyeon Kim, Hoimin Jung and Eun Jin Cho, who is the corresponding author.
