Chemical fixation of carbon dioxide to cyclic carbonates catalyzed by zinc(II) complex bearing 1,2-disubstituted benzimidazole ligand

Single-molecule magnet behaviour and catalytic properties of tetrahedral Co(ii) complexes bearing chloride and 1,2-disubstituted benzimidazole as ligands

“…Tetrabutylammonium iodide (TBAI), with I − anion being a better leaving group, showed only a moderate conversion (66%), while tetrabutylammonium chloride (TBAC) exhibits the lower activity among the tetrabutylammonium halides (TBAB (72%) > TBAI (66%) > TBAC (54%)). 28,90,91 This trend contrasts with that observed for a system using CoCl 2 /TBAX (TBAC > TBAB > TBAI), 92 indicating that the coordination of benzimidazole ligands to the metallic center modifies the reactivity pattern of the catalytic system. It has already been reported that ligand exchange equilibriums are involved in the formation of the catalytic active species in analogous systems.…”

“…S52, ESI†) as observed in the crystal packing of a related Zn( ii ) complex. 28 Only very weak intermolecular C–H⋯π, Cl⋯π and C–H⋯Cl type interactions occur for the present family of cobalt( ii ) complexes with the bulkier substituted imidazole ligands, namely compounds 1 and 3 . When the size of the imidazole derivative decreases (case of 4 and 5 ), π⋯π intramolecular interactions arise involving the imidazole and o -methoxy-phenylene groups in 4 [distance of 3.657(19) Å between the centroids of the rings involving the O2A and N1B atoms] or the imidazole and thiophene groups in 5 [distance of 4.2276(2) Å and 3.9343 Å between the centroids of the rings involving the S2A and N1 atoms and S2B and N1 atoms, respectively].…”

“…Our group has reported an active zinc( ii ) compound bearing 1,2-disubstituted-benzimidazole ligands to catalyse the transformation of several epoxides to cyclic carbonates. 28 Based on these results, we envisaged the possibility of using analogous cobalt( ii ) complexes as efficient catalysts since the Lewis acidity associated with the structural and coordinative flexibility of the Co II ion could lead to attractive catalytic performances in this transformation.…”

Single-component, metal-free, solvent-free HO-functionalized 1,2,3-triazole-based ionic liquid catalysts for efficient CO2 conversion

“…The use of cycloaddition reactions between CO 2 and epoxides to selectively produce cyclic organic carbonates (COCs) is a very effective method to fix this gas in the form of useful compounds due to the high atomic efficiency of the process and the large range of epoxides that can be used in this reaction, forming products with different properties and uses. 13–15 A variety of catalysts has been described to promote this transformation; in general, the most active catalysts are homogeneous metal complexes. 16–20 However, metal-free organocatalysts have gained a lot of attention, with the aim of making the process more environmentally friendly.…”

Novel Cobalt Complex as an Efficient Catalyst for Converting CO2 into Cyclic Carbonates under Mild Conditions

“…Owing to multiple metal coordination sites and the intermolecular interaction, supramolecular metal catalysts with high catalytic activity and selectivity have emerged as highly promising materials for wide applications, including the cycloaddition reaction of CO 2 [16][17][18]. It has been found that the 2 of 9 nitrogen-containing heterocyclic group possessed by the oligopyrazinediamine ligand has various coordination modes, which can be combined with transition metals under neutral conditions (for example, nickel, manganese, iron, cobalt, etc.)…”