Computational study on novel RhCpX (X = CF3, SiF3, CCl3, SO3H) as promising catalysts in the [3 + 2] azide–alkyne cycloaddition reaction: insights into mechanistic pathways and reactivity

Abstract

This computational study investigated the catalytic efficiency of novel RhCp^X complexes (X = CF₃, SiF₃, CCl₃, SO₃H) in [3 + 2] azide–alkyne cycloaddition reactions via density functional theory (MN12-L/Def2-SVP). Through quantum mechanical approaches, we explore the impact of different substituents on the Cp* ligand on the mechanism, selectivity, and reactivity of these Rh-based catalysts. Non-covalent interaction (NCI) and reduced density gradient (RDG) analyses, along with frontier molecular orbital (FMO) and Hirshfeld atomic charge analyses, were utilized to assess ligand stability and catalytic performance. The results show that RhCp^SO₃H offers the highest stability and reactivity, favoring the formation of 1,5-disubstituted triazoles. Our findings highlight the potential of these novel RhCp^X complexes as effective catalysts in synthetic and pharmaceutical applications.