Two novel alkaline earth coordination polymers constructed from cinnamic acid and 1,10-phenanthroline: synthesis and structural and thermal properties

Abstract

In coordination chemistry and crystal engineering, many factors influence the construction of coordination polymers and the final frameworks depend greatly on the organic ligands used. The diverse coordination modes of N-donor ligands have been employed to assemble metal-organic frameworks. Carboxylic acid ligands can deprotonate completely or partially when bonding to metal ions and can also act as donors or acceptors of hydrogen bonds; they are thus good candidates for the construction of supramolecular architectures. We synthesized under reflux or hydrothermal conditions two new alkaline earth(II) complexes, namely poly[(1,10-phenanthroline-κN,N')bis(μ-3-phenylprop-2-enoato-κO,O':O)calcium(II)], [Ca(CHO)(CHN)], (1), and poly[(1,10-phenanthroline-κN,N')(μ-3-phenylprop-2-enoato-κO:O,O':O')(μ-3-phenylprop-2-enoato-κO,O':O)barium(II)], [Ba(CHO)(CHN)], (2), and characterized them by FT-IR and UV-Vis spectroscopies, thermogravimetric analysis (TGA) and single-crystal X-ray diffraction analysis, as well as by powder X-ray diffraction (PXRD) analysis. Complex (1) features a chain topology of type 2,4 C4, where the Ca atoms are connected by O and N atoms, forming a distorted bicapped trigonal prismatic geometry. Complex (2) displays chains of topology type 2,3,5 C4, where the Ba atom is nine-coordinated by seven O atoms of bridging/chelating carboxylate groups from two cinnamate ligands and by two N atoms from one phenanthroline ligand, forming a distorted tricapped prismatic arrangement. Weak C-H...O hydrogen bonds and π-π stacking interactions between phenanthroline ligands are responsible to the formation of a supramolecular three-dimensional network. The thermal decompositions of (1) and (2) in the temperature range 297-1173 K revealed that they both decompose in three steps and transform to the corresponding metal oxide.

A new chiral rare-earth organic framework constructed by tartaric acid: synthesis, structural, thermal investigations and optical properties

“…This technique has earned enormous importance due to its simplicity and the tremendous results seen regarding the production of CMCPs (Amo-Ochoa et al, 2007;Fu et al, 2008;Sabo et al, 2007). Hydrothermal reactions are affected by a variety of parameters, such as reaction time, temperature and pH value (Bendjellal et al, 2018;Loiseau & Fe ´rey, 2007;Wang et al, 2009;Zhang et al, 2009), and are often quite complicated and may involve in situ metal-ligand reactions, such as hydrolysis, substitution and oxidation (Xiong et al, 2002;Fe ´rey, 2001;Szeto et al, 2006;Wang et al, 2008). Although it is not always possible to exert synthetic control, a fascinating variety of novel CMCPs has been obtained from hydrothermal reactions (Qi et al, 2013;He et al, 2008He et al, , 2009Geng et al, 2009;Yin et al, 2009;Jiang et al, 2010;Zhan et al, 2010;Lv et al, 2010).…”

A novel three-dimensional copper aspartate coordination compound with efficient photoluminescence

“…Although great efforts have been put into the design and construction of MOFs, controlling the structures as well as regulating the functions of MOFs still remains a challenge because the design and synthesis of MOFs are influenced by many factors, such as the nature of the metal ions, organic ligands, and solvents, as well as the temperature and pH value [6,7]. The existing protocols have proven that reasonable selection of organic linkers is essential for the construction and control of properties of MOFs [8,9]. Among the various organic linkers, amino acids have been widely used in the preparation of MOFs since they have multiple binding sites and versatile bonding modes provided by amino and carboxylate groups [10].…”

Synthesis, crystal structure and photoluminescence of a three-dimensional zinc coordination compound with NBO-type topology

“…Controlling the structures and regulating the functions of MOFs remains a big challenge since the design and synthesis of MOFs are influenced by many factors, such as the metal ions, organic ligands, solvents, temperature and pH value (Sun et al, 2017;Zhou et al, 2017). The large number of obtained MOF products has proved that the reasonable selection of organic linkers is an efficient approach for the construction and the control of properties of MOFs (Bendjellal et al, 2018;Tao et al, 2017). Among various organic linkers, aromatic polycarboxylates have been widely used in the preparation of MOFs since they have many coordination modes and can thus form diverse structures and also may act as hydrogen-bond acceptors and donors in the assembly of supramolecular structures (Lin et al, 2008;Cui et al, 2009).…”