Year: 2026
Type: article
Abstract: α‐Cationic phosphine ligands are strong π‐acceptors that significantly enhance the electrophilicity of transition‐metal centers. Herein, we demonstrate their effectiveness in cobalt‐catalyzed [2+2+2] cyclotrimerization of alkynes, enabling the efficient synthesis of trisubstituted benzenes under mild conditions. The use of these ligands leads to a marked increase in catalytic activity, allowing reactions to proceed at room temperature and with catalyst loadings as low as 2 mol%. Results obtained with two different α‐cationic phosphines, cyclopropenio‐ and pyridiniophosphine, suggest that enhanced π‐backdonation to the α‐cationic phosphine increases the electrophilicity of the cobalt center, thereby promoting cyclization. The methodology displays broad substrate scope and high regioselectivity, including challenging sterically hindered alkynes. These results highlight the potential of α‐cationic phosphines to boost the performance of earth‐abundant metal catalysts and advance sustainable catalytic strategies.
Source: Advanced Synthesis & Catalysis
DOI: 10.1002/adsc.70838
Institution: Universitat de València
Language: English
Topic: Catalytic Alkyne Reactions
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,650
Funder: Generalitat Valenciana
OpenAlex ID: W7224487501