Extending framework based on the linear coordination polymers: Alternative chains containing lanthanum ion and acrylic acid ligand

One-dimensional alternative chains of two lanthanum complexes: [La(L1)3(CH3OH)(H2O)2]·5H2O (L1=anion of α-cyano-4-hydroxycinnamic acid ) 1 and [La(L2)3(H2O)2]·3H2O (L2=anion of trans-3-(4-methyl-benzoyl)-acrylic acid) 2 were synthesized and structurally characterized by single-crystal X-ray diffraction, element analysis, IR and thermogravimetric analysis. The crystal structure data are as follows for 1: C31H36LaN3O17, triclinic, P  -1, a=9.8279(4)Å, b=11.8278(5)Å, c=17.8730(7)Å, α=72.7960(10)°α=72.7960(10)°, β=83.3820(10)°β=83.3820(10)°, γ=67.1650(10)ºγ=67.1650(10)º, Z=2Z=2, R1=0.0377R1=0.0377, wR2=0.0746wR2=0.0746; for 2: C33H37LaO14, triclinic, P  -1, a=8.7174(5)Å, b=9.9377(5)Å, c=21.153(2)Å, α=81.145(2)°α=81.145(2)°, β=87.591(2)°β=87.591(2)°, γ=67.345(5)°γ=67.345(5)°, Z=2Z=2, R1=0.0869R1=0.0869, wR2=0.220wR2=0.220. 1 is a rare example of the alternative chain constructed by syn–syn and anti–syn coordination mode of carboxylato ligand arranged along the chain alternatively. La(III) ions in 2 are linked by two η3–O bridges and four bridges (two η2–O and two η3–O) alternatively. Both of the linear coordination polymers grow into two- and three-dimensional networks by packing through extending hydrogen-bond network directed by ligands.

3D H-bonding network directed by the ligand based on the rare alternative chain of lanthanum complex containing syn–syn and anti–syn coordination mode of α-cyano-4-hydroxycinnamic acid.Figure optionsDownload as PowerPoint slide