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

Abstract

One-dimensional alternative chains of two lanthanum complexes: [La( L 1) 3(CH 3OH)(H 2O) 2]·5H 2O ( L 1=anion of α-cyano-4-hydroxycinnamic acid ) 1 and [La( L 2) 3(H 2O) 2]·3H 2O ( L 2=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: C 31H 36LaN 3O 17, triclinic, P-1, a = 9.8279 ( 4 ) Å , b = 11.8278 ( 5 ) Å , c = 17.8730 ( 7 ) Å , α = 72.7960 ( 10 ) ° , β = 83.3820 ( 10 ) ° , γ = 67.1650 ( 10 ) º , Z = 2 , R 1 = 0.0377 , w R 2 = 0.0746 ; for 2: C 33H 37LaO 14, triclinic, P-1, a = 8.7174 ( 5 ) Å , b = 9.9377 ( 5 ) Å , c = 21.153 ( 2 ) Å , α = 81.145 ( 2 ) ° , β = 87.591 ( 2 ) ° , γ = 67.345 ( 5 ) ° , Z = 2 , R 1 = 0.0869 , w R 2 = 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 η 3–O bridges and four bridges (two η 2–O and two η 3–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.