A series of 1-D zinc(II) coordination polymers with 3-D supramolecular networks: synthesis, structural investigation, and NBO analysis


Zahedi M., Shaabani B., Radyousefnia N., Englert U., Blake G. R., AYGÜN M.

JOURNAL OF COORDINATION CHEMISTRY, vol.71, no.24, pp.4031-4046, 2018 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 71 Issue: 24
  • Publication Date: 2018
  • Doi Number: 10.1080/00958972.2018.1539713
  • Journal Name: JOURNAL OF COORDINATION CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.4031-4046
  • Keywords: Coordination polymers, bipyridine analogue ligand, natural bond orbital analysis (NBO), thermal analysis, luminesence, CRYSTAL-STRUCTURES, X-RAY, LIGAND, LUMINESCENCE, CONSTRUCTION, TOPOLOGIES, LONG, DICARBOXYLATES, COMPLEXES, ACETATE
  • Dokuz Eylül University Affiliated: Yes

Abstract

N,N '-Bis(pyridin-4-ylmethylene)naphthalene-1,5-diamine (L) acts as a bipyridine analogue linker ligand towards {Zn-7(mu(4)-O)(2)(OAc)(10)}, {Zn-2(NCS)(2)(OAc)(2)}, and {Zn(N-3)(2)} nodes and allows construction of three new 1-D coordination polymers, the linear chain [Zn-7(mu(4)-O)(2)(OAc)(10)(L)](n) (1), [Zn(NCS)(OAc)(L)](n) (2) in ladder-type geometry and the zigzag chain [Zn(N-3)(2)(L)](n) (3). Structural characterization reveals that in 1 acetate anionic ligands connect seven Zn(II) ions through the bridging coordination modes mu(3)-eta(1),eta(2) and mu(2)-eta(1),eta(1). The resulting heptanuclear node is located on an inversion center and therefore consists of four crystallographically distinct cations; their coordination spheres correspond to distorted octahedra or tetrahedra. The Zn(II) ions in polymer 2 exhibit distorted trigonal bipyramidal {ZnN3O2} coordination; mu(2)-eta(1),eta(1) coordinated acetate and terminal thiocyanate ligands lead to inversion-symmetric [Zn-2(NCS)(2)(OAc)(2)] secondary building units (SBU), which are further linked by the N,N '-bipyridine analogue L. Terminal coordination of two anionic azide ligands and the bridging bipyridine L result in coordination polymer 3, in which the cations adopt distorted tetrahedral {ZnN4} coordination. In all crystalline solids 1-3, adjacent 1-D chains interact through pi-pi stacking and non-classical (C - H center dot center dot center dot O, C - H center dot center dot center dot pi) hydrogen bonds, leading to 3-D supramolecular architectures. Differences in their 3-D arrangement are due to variations in the anionic co-ligands, subtle conformational differences in the semi-rigid linker and the variable coordination sphere about the zinc cations. Thermogravimetric investigations indicate differences in both thermal stability and decomposition mode. Natural bond orbital (NBO) analysis provides a convenient basis for investigating the intramolecular bonding interactions and delocalization effects in these molecular systems. Finally, solids 1-3 exhibit intense luminescence at room temperature.