A family of double-layered octahedral coordination networks built up from divalent metal ions, formate anions, and ethyl carbazate ligands: M (CHO₂)₂(C₃H₈N₂O₂) (M = Co, Zn, Cd)

Abstract

The syntheses, structures, and characterization (IR, TGA/DTA, UV/visible spectroscopy) of an isostructural family of layered coordination networks containing divalent metal ions (Co²⁺, Zn²⁺, and Cd²⁺), formate (ft) anions and neutral C₃H₈N₂O₂ ethyl carbazate (ec) ligands of formula M(ft)₂(ec) are described. A manganese-containing compound with the same stoichiometry possibly adopts the same structure. Single-crystal structures of the zinc and cadmium phases show the presence of distorted ZnO₅N and CdO₅N octahedra, in which ec adopts N,O-bidentate coordination, and four monodentate ft anions bridge to adjacent metal ions. This connectivity leads to polymeric sheets built up from double octahedral layers propagating in the (001) plane. The crystal structures are completed by N–H ··· O and N–H ··· (O,O) hydrogen bonds. Crystal data: Zn(CHO₂)₂(C₃H₈N₂O₂), M _r = 259.52, triclinic, (No. 2), a = 8.0848(2) Å, b = 8.7345(1) Å, c = 13.2841(3) Å, α = 74.2839(14)°, β = 86.7150(12)°, γ = 89.4713(15)°, V = 901.51(3) ų, Z = 4, R(F) = 0.024, wR(F ²) = 0.056. Cd(CHO₂)₂(C₃H₈N₂O₂), M _r = 306.55, triclinic, (No. 2), a = 8.4574(2) Å, b = 8.9112(3) Å, c = 13.5119(5) Å, α = 73.101(1)°, β = 86.366(2)°, γ = 89.420(2)°, V = 972.36(5) ų, Z = 4, R(F) = 0.022, wR(F ²) = 0.053.

Keywords:

• Layered coordination network
• Formate anion
• Bidentate ligand
• Crystal structure