ABSTRACT
In the crystal structure of the title compound, [Cu(NO3)2(C3H5N3)4], the CuII atom is situated on an inversion center (Wyckoff position 2c of space group P21/n) and shows an octa-hedral [N4O2] coordination environment. The axial positions are occupied by O atoms of nitrate anions, while the equatorial positions are taken up by the N atoms of four 3-amino-pyrazole ligands. As a result of the tautomerism of the latter, two coordinate with the N1-atom of 3-amino-pyrazole while the other two with the N2-atom. The presence of pyrrole-like N-H groups and amine substituents as donor groups leads to numerous intra- and inter-molecular hydrogen-bonding inter-actions, which were qu-anti-fied by Hirshfeld surface analysis.
ABSTRACT
In the title bicyclic trinuclear pyrazolate amino-alcohol complex, [Cu3(C5H7N2)2(C6H14NO3)2]Br2·1.5H2O, the central Cu atom lies on a center of symmetry and is involved in the formation of two five-membered rings. It has a coordination number of 4, is in a distorted tetra-hedral environment and is connected by the bridging oxygen atoms of the deprotonated OH groups of different amino-alcohol groups, and by the N atoms of deprotonated di-methyl-pyrazole ligands. The peripheral Cu atom is in a trigonal-bipyramidal coordination environment formed by the nitro-gen atom of the deprotonated bridging di-methyl-pyrazole unit, the bridging oxygen atom of the deprotonated OH group, two oxygen atoms of the protonated hy-droxy groups and the nitro-gen atom of tri-ethano-lamine. One of the C atoms and the Br- anion were found to be disordered over two positions with occupancy factors of 0.808â (9):0.192â (9) and 0.922â (3):0.078â (3), respectively.
ABSTRACT
In the title compound [Fe(bpe)(Hbpe)Au(CN)2][Au(CN)2]2·bpe·2H2O} n [where bpe = 1,2-bis-(pyridin-4-yl)ethene, C12H10N2], the FeII ion is coordinated in a distorted octa-hedral [FeN4O2] environment by two di-cyano-aurate anions, two water mol-ecules and two partially protonated 1,2-di(4-pyrid-yl)ethyl-ene mol-ecules. Di-cyano-aurate anions bridge the FeII cations, forming infinite chains, which propagate along the a-axis direction. The chains are connected via aurophilic inter-actions with two non-coordinated di-cyano-aurate anions for each FeII ion. The polymeric chains inter-act with each other via π-π stacking between the guest bpe mol-ecules and multiple hydrogen bonds.
ABSTRACT
In the asymmetric unit of the title coordination compound, {[Cu(CN)(C4H3OC2H5N2)][Cu(CN)]} n , there are two Cu atoms with different coordination environments. One CuI ion is coordinated in a triangular coordination geometry by the N atom of the 2-eth-oxy-pyrazine mol-ecule and by two bridging cyanide ligands, equally disordered over two sites exchanging C and N atoms, thus forming polymeric chains parallel to the c axis. The other Cu atom is connected to two bridging cyanide groups disordered over two sites with an occupancy of 0.5 for each C and N atom, and forming an almost linear polymeric chain parallel to the b axis. In the crystal, the two types of chain, which are orthogonal to each other, are connected by cuprophilic Cuâ¯Cu inter-actions [2.7958â (13)â Å], forming two-dimensional metal-organic coordination layers parallel to the bc plane. The coordination framework is further stabilized by weak long-range (electrostatic type) C-Hâ¯π inter-actions between cyano groups and 2-eth-oxy-pyrazine rings.
ABSTRACT
In the title metal-organic framework, [Fe(C6H8N2)2{Cu(CN)2}2] n , the low-spin FeII ion lies at an inversion centre and displays an elongated octa-hedral [FeN6] coordination environment. The axial positions are occupied by two symmetry-related bridging 2-ethyl-pyrazine ligands, while the equatorial positions are occupied by four N atoms of two pairs of symmetry-related cyanide groups. The CuI centre is coordinated by three cyanide carbon atoms and one N atom of a bridging 2-ethyl-pyrazine mol-ecule, which form a tetra-hedral coordination environment. Two neighbouring Cu atoms have a short Cuâ¯Cu contact [2.4662â (7)â Å] and their coordination tetra-hedra are connected through a common edge between two C atoms of cyanide groups. Each Cu2(CN)2 unit, formed by two neighbouring Cu atoms bridged by two carbons from a pair of µ-CN groups, is connected to six FeII centres via two bridging 2-ethyl-pyrazine mol-ecules and four cyanide groups, resulting in the formation of a polymeric three-dimensional metal-organic coordination framework.
