Fine-tuning on the structures of 3D CoII/5-methylnicotinate coordination polymers via three different synthetic approaches

•Three 3D coordination polymers are assembled from CoII and 5-methylnicotinic acid under three different synthetic routes.•The synthetic methods include layer diffusion, solvothermal, and ambient stirring.•Three diverse nets in topologies of dia, noz, and lvt are obtained.•Thermal stability of the complexes is also studied.

Three distinct 3D Co(II) coordination polymers have been prepared based on Co(OAc)2 and 5-methylnicotinate ligand (L-CH3) via different synthetic approaches, including layer diffusion, solvothermal synthesis, and ambient stirring method. Through the layer diffusion method, a 3D framework {[Co(L-CH3)2(H2O)0.5](CH3OH)1.25}n (1) can be obtained, which displays a 4-connect (66) dia topological network. Employment of solvothermal synthesis affords another 3D framework {[Co2(L-CH3)4(H2O)](H2O)}n (2), which shows a 5-connected (44 · 66) noz topology. {[Co(L-CH3)2(H2O)2](H2O)}n (3) can be produced from the ambient stirring method, featuring the 4-connected (42 · 64) lvt topology. These results demonstrate that fine-tunning on the diverse coordination motifs of 1–3 can be readily achieved by selecting proper synthetic approaches. In addition, thermal stability property of these complexes is also studied.

Graphical abstractThree distinct 3D CoII coordination polymers with 5-methylnicotinate ligand have been isolated through three different synthetic approaches, including layer diffusion, solvothermal, and stirring methods, which show the interesting dia, noz, and lvt topological nets, respectively.Figure optionsDownload full-size imageDownload as PowerPoint slide