Construction of Nano-Channels Based on Zinc(II) Pyrazine-2-carboxylate Complexes

The reaction of pyrazine‐2‐carboxylate (pca) and bis(pyridine) derivatives, such as 4,4′‐bipyridine (bipy), 1,2‐bis(4‐pyridyl)ethylene (bpen), 1,2‐bis(4‐pyridyl)ethane (bpea), 1,3‐bis(4‐pyridyl)propane (bpp), and 4,4′‐azopyridine (azp), with zinc perchlorate gives supramolecules with grid and/or channel structures. The new complexes reported here are trans‐[Zn(bipy)(pca)(H2O)]ClO4·(EtOH)0.5·(H2O)0.5 (1), [Zn(μ‐bpen)(bpen)(pca)(H2O)]·ClO4·2H2O (2), [Zn(bpea)(pca)]ClO4·(EtOH)0.5 (3), and [Zn(bpp)(pca)(MeOH)]ClO4 (4). Their structures have been established by single‐crystal X‐ray diffraction. Some of these complexes contain voids with nanometer dimensions. Small molecules such as H2O, MeOH, and EtOH contained in these voids can be removed without destruction of the parental suprastructure. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)