A Novel Triangular Trinuclear μ3-CO3 Ferromagnetic CuII Compound Prepared in situ from CO2 Uptake in Air. X-ray Structure, Spectroscopy and Magnetism

Abstract

The new trinuclear compound [Cu3(bpy)6(μ3‐CO3)](BF4)4(H2O)2(C2H6O) (in which bpy = 2,2′‐bipyridine) has been synthesized from Cu(BF4)2 and bpy in aqueous ethanol by rapid uptake of atmospheric CO2. The structure of the compound has been determined by X‐ray crystallography; it was found to crystallise in the triclinic space group P1¯ with a = 13.405(7), b = 13.691(7), c = 21.446(8) Å, α = 82.87(4), β = 73.57(4), γ = 64.32(4)°, Z = 2. The three copper atoms are connected to each other through the oxygen atoms from the bridging carbonato group, giving a triangular array of copper atoms. Each copper has a distorted square‐pyramidal environment with a basal plane formed by three nitrogen atoms of the two chelating bipyridine groups and the oxygen atom of the bridging carbonato group (Cu−N/O distances about 2.0 Å). The apical position is formed at each copper by the fourth nitrogen atom of the bipyridines with distances varying from 2.120(5) to 2.188(5) Å. A weak ferromagnetic interaction is observed between the copper(II) ions. All data were fitted using the Hamiltonian H = −J12 (S1·S2) −J13 (S1·S3) −J23 (S2·S3). Observed parameters are J = 10.6 cm−1 and a very weak antiferromagnetic intercluster interaction with zj′ = −1.2 cm−1.

A novel μ3-CO3 bridged linear polymeric Cu-complex ([Cu3(DMAP)8(μ3-CO3)2]I2)n·xH2O: synthesis, characterization and catalytic applications in the synthesis of phenoxypyrimidines and arylthiopyrimidines via C–O and C–S cross-coupling reactions

“…There are literature reports available supporting atmospheric CO 2 xation as a possible source of CO 3 2− in the synthesis of carbonato-bridged copper(II) complexes. 11,64 Aer the complete characterization of the synthesized polymeric Cu-complex, we checked its catalytic activity in the synthesis of phenoxypyrimidines via C-O cross-coupling reactions. For that, we took a model reaction between 6-chlorouracil (1a) and phenol (2a) (Scheme 2) and carried out a series of reactions in the presence of ([Cu 3 (DMAP) 8 (CO 3 ) 2 ]I 2 ) n $xH 2 O in different solvents and base combinations.…”

“…There are literature reports available supporting atmospheric CO 2 fixation as a possible source of CO 3 2− in the synthesis of carbonato-bridged copper( ii ) complexes. 11,64…”

Carbon dioxide uptake by [Cu(bpca)]+: synthesis, crystal structure, and magnetic properties of {[Na(H2O)2][Cu2(bpca)2(CO3)(HCO3)]}n [Hbpca = bis(2-pyridylcarbonyl)amide]

“…62 Since then, many reports have been devoted to the somewhat unexpected spontaneous fixation of CO 2 by metal complexes to afford carbonate-containing compounds. 63–96 Nonetheless, apart from the structural control and predictability of these materials, the investigation of their cryomagnetic behaviour has attracted the attention of different research teams, as described below.…”