Multinuclear metal catalysts in ring-opening polymerization of ε‑caprolactone and lactide: Cooperative and electronic effects between metal centers

An octanuclear nickel(II) pyrazolate cluster with a cubic Ni8 core and its methyl- and n-octyl-functionalized derivatives

“…Polynuclear metal-organic complexes display interesting properties that allow for numerous applications in fields such as molecular magnetism (Milios & Winpenny, 2015;Papatriantafyllopoulou et al, 2016;Zheng et al, 2018;Li et al, 2022), luminescence (Yam & Lo, 1999;Balzani et al, 1996) and catalysis in organic synthesis (Nath et al, 2020;Singh et al, 2020;Wu et al, 2023). Discrete polynuclear clusters with their metal ions arranged in various different geometries have been reported, including grids (Ruben et al, 2004), macrocycles (Yang, 2018;Zaleski, 2022), and Platonic and Archimedean solids (Luo et al, 2023).…”

Comparative Study of Aluminum Complexes Bearing N,N′-Diaryldioxalamidate and N,N′-Diaryldithiooxalamidate Ligands in Ring-Opening Polymerization of ε-Caprolactone

“…Poly-ε-caprolactone (PCL) − is a commercially available and popular material because of its biodegradable property, and it can be used to replace petrochemical plastics to solve environmental pollution caused by discarded plastic waste with slow decomposition naturally. − In addition, PCL-based biomaterials with biocompatibility − and permeability can be used in various fields. − The Lewis acidic-catalyzed ring-opening polymerization (ROP) of ε-caprolactone (CL) − is a primary method for manufacturing PCL. Al complexes are useful catalysts with a high catalytic conversion of CL polymerization, and various types of ligands, such as O,O type (diphenolate − ), N,O type (Schiff base − and aminophenolate − ), N,S type (thio-Schiff base), and N,N type (β-diketiminate − and anilido-pyrazolate), were used to synthesize Al catalysts for CL polymerization.…”

Bimetallic polymerization of lactide with binaphthol-derived bis-heteroscorpionate dizinc and dimagnesium complexes

“…13 Mechanistic analysis has shown that monomer insertion is a bifunctional process that can be accelerated by metal–metal cooperation in this situation. 14 For this reason, there has been increasing interest in discrete bimetallic precatalysts for lactone polymerization using binucleating ligands (Fig. 1A), 15 with the goal of controlling and analyzing metal–metal cooperativity with the same flexibility as in single-site catalysts.…”