Encapsulation of atmospheric CO2 by a self-assembled decanuclear cadmium complex via unfamiliar perchlorato and carbonato bridges

Abstract

A decanuclear Cd complex has been found as a carbonate-containing capsule. The structure strongly resembles a ten-blade waterwheel with a central carbonate ligand surrounded by two superimposed Cd(5)O(5) crowns with a pentagonal antiprism-like disposition. The capsule is doubly capped by two pentadentate perchlorate anions.

Metal–salen molecular cages as efficient and recyclable heterogeneous catalysts for cycloaddition of CO2 with epoxides under ambient conditions

“…The homogeneous metal salts Co(OAc) 2 ·4H 2 O and Al(OEt) 3 exhibited much lower reactivity (59% and 24%, entries 9 and 10) as compared to the heterogeneous Co( iii )@cage and Al( iii )@cage. Previous reports on utilizing molecular cage complexes for CO 2 cycloaddition are rare, although some molecular cages showed selective uptake of CO 2 20,30 and were able to trap CO 2 as carbonate anions within the cage framework 31. In 2014, Martinez and Dufaud demonstrated that an azaphosphatrane–hemicryptophane cage complex was able to catalyze the CO 2 cycloaddition to give styrene carbonate in 82% yield at 100 °C and 1 atm CO 2 32…”

New coordination features; a bridging pyridine and the forced shortest non-covalent distance between two CO32−species

“…spheric carbon dioxide under strong basic conditions by incorporation into transition metal complexes is now very well documented. [35][36][37] Fixation of more than one carbonate unit by one molecule is much rarer. In such cases, these species usually act essentially as spacers between metals or are subtended by metal ions conforming the external surface of a cage.…”

Self-assembled supramolecular structures of O,N,N′ tridentate imidazole–phenol Schiff base compounds

“…21 Solid state structures of the related free ligand structures derived from 2-aminophenol and imidazole-, pyrrole-and pyridine-2-carboxaldehyde have been also reported. [22][23][24][25] With only metal complexes of ligands (e) and (h) previously reported, 18,20 literature related to the solid state structures of tridentate O,N,N 0 -1-methyl-2-imidazolephenol Schiff base molecules is scarce. There are no free ligand structures reported for this class of compound.…”