Macrocyclic dinuclear, helical, layered and 3-D Ag(I) complexes constructed from AgX (X = NO3(-) and ClO4(-)) and flexible bis(pyridyl) ligands with a chelating spacer: syntheses, structures and photoluminescence properties

Dalton Trans. 2015 Mar 28;44(12):5837-47. doi: 10.1039/c5dt00265f.

Abstract

Reaction of AgX (X = NO3− and ClO4−) and three flexible bis(pyridyl) ligands with a chelating spacer leads to the formation of eight novel Ag(I)-bis(pyridyl) coordination complexes: {[Ag2L1(NO3)2]n·2nH2O} (1), {[AgL1]n·nClO4} (2), {[AgL2]n·nNO3} (3), {[AgL2]n·nClO4} (4), [Ag2(H2L2)2]·6ClO4·9H2O (5), {[AgL3]n·nNO3·nH2O} (6), {[AgL3]n·nClO4·nH2O} (7), and {[Ag3(L3)2(ClO4)]n·2nClO4} (8) (L1 = N,N′-bis(pyridin-2-ylmethyl)propane-1,3-diamine, L2 = N,N′-bis(pyridin-3-ylmethyl)propane-1,3-diamine, L3 = N,N′-bis(pyridin-4-ylmethyl)propane-1,3-diamine), which have been characterized by elemental analysis, IR, TG, UV-Vis DRS, PL, powder and single-crystal X-ray diffraction. Complex 1 presents a (4,4) layered motif which is furnished by the bridging of L1 molecules and nitrate anions in μ4 (κ1N1:κ1N2:κ1N3:κ1N4) and μ2 (κ1O4:κ1O6) modes. With a different μ2 (κ1N1:κ1N2:κ1N3:κ1N4) mode, L1 molecules in complex 2 join the adjacent Ag(I) cations to form a helical chain structure. Complexes 3 and 4 also show helical chain structures with the L2 molecules displaying the same μ3 (κ1N1:κ1N2:κ1N3:κ1N4) mode. The protonation of –NH– groups in the chelating spacer leads to the formation of H2L22+ cations which further results in a macrocyclic dinuclear motif in complex 5. Complexes 6 and 7 are 3-D svi-x nets with the counter-anions and lattice water molecules being encapsulated in the 1-D channels. Complex 8 exhibits a snake-shaped chain with the L3 molecules presenting μ3 (κ1N:κ1N′:κ1N″:κ1N) mode. The structural diversities of complexes 1–8 can be attributed to the coordination modes and conformations of L1–L3. The photoluminescence properties demonstrate that complexes 1, 2 and 5 exhibit ligand-based blue emission maxima from 455 to 462 nm at room temperature in the solid state.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 2,2'-Dipyridyl / chemical synthesis
  • 2,2'-Dipyridyl / chemistry*
  • Chelating Agents / chemical synthesis
  • Chelating Agents / chemistry*
  • Coordination Complexes / chemical synthesis
  • Coordination Complexes / chemistry*
  • Ligands
  • Luminescent Agents / chemical synthesis
  • Luminescent Agents / chemistry*
  • Macrocyclic Compounds / chemical synthesis
  • Macrocyclic Compounds / chemistry*
  • Models, Molecular
  • Silver / chemistry*

Substances

  • Chelating Agents
  • Coordination Complexes
  • Ligands
  • Luminescent Agents
  • Macrocyclic Compounds
  • Silver
  • 2,2'-Dipyridyl