Ambient chemical fixation of CO₂ using a highly efficient heterometallic helicate catalyst system

Abstract

Two novel heptanuclear 3d-4f helicates have been synthesized and characterized. The helicates act as catalysts and show high catalytic activity for the coupling of CO and epoxides to obtain cyclic carbonates with a wide substrate scope at ambient temperature and pressure.

Rational Stepwise Construction of Different Heterometallic–Organic Frameworks (HMOFs) for Highly Efficient CO2 Conversion

“…Nevertheless, it is difficult to controlt he formation of HMOFs, because there are variousp arameters influencing the synthesis of HMOFs, such as groups in the ligands, coordinationnumbers of metal ions, solventsystem,pHvalues of solutions, reaction temperature, and the ratio of metal-to-ligand, etc. [10][11][12][13][14][15][16][17][18] In this work, ab ifunctional2 -(imidazol-1-yl)terephthalic acid (H 2 L) ligand was chosen to build new HMOFso wing to:( i) the presence of both nitrogen and oxygen donor atoms in the ligand, ( (4), have been effectively and rationally constructed from complexes 1 and 2 as the precursors, respectively (Scheme 1). Moreover, thes ynthesized HMOFs bearing dual catalytics ites (Tb and Ag) can be used as heterogeneous catalysts for the chemical fixationo fC O 2 with epoxides,i ncluding sterically hindered epoxides.…”

Transformative 3d–4f coordination cluster carriers

“…108 So far there have been two reports of 3d-4f CCs used as catalysts for the cycloaddition of styrene oxides and CO2 to obtain cyclic carbonates. 109,110 The first of these described two isoskeletal heptanuclear 3d-4f CCs, which were synthesised from the "helical" HL31 ligand 2(μ3 -OH)2(L32)4(OAc)6(NO3)2] (39-ZnLn) respectively are described (Figure 9). Single-crystal X-ray structural analysis and a variety of characterisation methods were used to confirm the structure of all these 3d-4f CCs and revealed the two metal centres of Ln and Zn were situated in the correct range to enable synergistic action as Lewis acid activators.…”

A tetranuclear CuII2DyIII2 coordination cluster as a Suzuki (C–C) coupling reaction promoter

“…7 Our group has established the efficacy of a series of tetranuclear [M II 2Ln III 2L4(X)2(solv)2] (M = Ni, Co, Cu, Zn, X = Cl, NO3, Ln = Y, Dy, Gd) for domino-electro cyclization and Lewis acid reactions, [8][9][10][11] whereas other groups have, successfully, used them in redox, [12][13][14] co-polymerization 15 and carbon dioxide fixation reactions. 16,17 The metal-promoted Suzuki-Miyaura coupling includes organoboron derivatives and carbon electrophiles, and represents a valuable procedure for a C-C bond formation (Scheme 1). 18 This synthetic protocol uses commercially available boron reactants, which are relatively stable, non-toxic and can be easily functionalized.…”