ИСТИНА

Metal-organic frameworks (MOFs) have been attracting great interest in the past decades due to their fascinating architectures and potential application in many areas. Recent progress in reticular chemistry and data analysis of coordination polymers and MOFs allows new directions for developing the syntheses of coordination polymers with a desired mutual disposition of ligands. Knowledge databases collecting information about typical coordination modes of ligands, metal environment, occurrences of underlying nets and relations between composition of a complexes, and topology of its' underlying net allow prediction of the most abundant composition, connectivity and periodicity even for multicomponent reaction mixtures in a quantitative manner. We applied an algorithm of such prediction to M : An2- : L : H2O mixtures (M = CoII, CuII, NiII, ZnII; An2- = derivatives of the malonic acid; L = analogs of 4,4'-bipyridine). We found that novel compounds obtained from such mixtures realize highly probable compositions, MII environment and ligand connectivities.1 The majority of these complexes also have one of the predicted topologies of underlying nets and only few form novel networks. A series of isoreticular coordination polymers containing malonate derivatives and analogues of 4,4′-bipyridine were isolated. The effects of the precursor, either M(II) nitrate or M(II) acetate, on the composition and dimensionality of the resulting architecture are discussed. Some of complexes containing 1,2-bis(pyridin-4-yl)ethylene were found to have close packing of ethylene groups (<4.2 Å). We succeeded in carrying out a photoinitiated [2 + 2] cycloaddition reaction for these compounds in a single-crystal-to-single-crystal manner. The 3D→3D (with network change), 3D→3D (with a constant net topology) and 0D→1D transformations of complexes were observed. Among them the first diastereoselective solid-state crossed photocycloaddition of olefins in a 3D Zn(II) coordination polymer was characterized by means of XRD.2 A racemic mixture of two enantiomers of an unsymmetrical (1R,2S,3S)-substituted cyclobutane derivative was synthesized in high yield (75% based on XRD data, and 80% based on 1H NMR data) without any solvents or catalysts. Overall, potential of reticular chemistry and knowledge databases in the synthesis of coordination polymers with desired disposition of ligands (particularly, photosensitive) was demonstrated.