Porous homo- and heterochiral cobalt(II) aspartates with high thermal stability of the metal-organic framework

Metal-organic coordination polymers with the compositions [Co2(L-asp) 2-(bpy)] · MeOH · H2O (1), [Co2(L-asp)2(bpe)] · 0.28(bpe) · H2O (2), and [Co2(d-asp)(l-asp)-(bpa)] · 0.25(bpa) · 1.5H2O (3) (H2asp is aspartic acid, bpy is 4,4′-bipyridine, bpe is trans-bis(4- pyridyl)ethylene, and bpa is 1,2-bis(4-pyridyl)ethane) were synthesized on heating cobalt(II) as-partate and N-donor ligands (bpy, bpe, or bpa) in an aqueous-methanol mixture. The structures of compounds 1⁗ash;3 were established by X-ray diffraction analysis and confirmed by X-ray powder crystallography, IR spectroscopy, thermogravimetry, and elemental analysis. The stability of the synthesized coordination polymers was studied. It was shown that they retain the framework structure on heating to 300 °C.