Synthesis, Hirshfeld surface analysis, luminescence and thermal properties of three first‐row transition metal complexes containing 4′‐hydroxy‐2,2′:6′,2″‐terpyridine: Application for preparation of nano metal oxides

Abstract

A series of new mono‐ and bis‐terpyridine complexes [Mn(tpyOH)Cl2] (1), [Ni(tpyOH)2](PF6)2 (2) and [Zn(tpyO)(η1‐OCOCH3)(H2O)]⋅3H2O (4) containing 4′‐hydroxy‐2,2′:6′,2″‐terpyridine (tpyOH) were synthesized and structurally characterized using elemental analysis, infrared spectroscopy and single‐crystal X‐ray diffraction. The reaction of MnCl2 with tpyOH in a mixture of methanol and CH2Cl2 resulted in the formation of 1. The X‐ray crystal structure of 1 reveals that Mn(II) is penta‐coordinated by three nitrogen atoms from tpyOH and two Cl− in a slightly distorted trigonal bipyramidal geometry. Complex 2 was also prepared by the reaction of nickel(II) chloride with tpyOH in a methanolic medium in the presence of NH4PF6. Notably, the complex [Ni(tpyOH)(tpyO)]PF6 (3), obtained during the crystallization of 2 from dichloromethane, was characterized using X‐ray crystallography which shows that six nitrogen atoms from terpyridine ligands occupy the coordination sites around the Ni(II) centre in a distorted octahedral geometry with four longer bonds and two shorter NiN bonds. The reaction of zinc(II) acetate with tpyOH in a mixture of methanol and CH2Cl2 led to the formation of 4. The crystal structure of 4 reveals the formation of penta‐coordinated Zn(II) complex containing three nitrogen atoms from tpyO, a monodentate acetate ligand and one coordinated water molecule. Hirshfeld surface analyses and two‐dimensional fingerprint plots show that the main interactions are O…H/H…O contacts in 1, 3 and 4. The thermal decomposition reactions of 1, 2 and 4 were studied using thermogravimetric analysis in detail due to their different structures. The solution luminescence features of 1, 2 and 4 include high‐energy intense π → π* intraligand and low‐energy metal‐to‐ligand charge transfer transitions at room temperature. The calcination of the coordination complexes led to the formation of corresponding nano metal oxides. The products were structurally characterized using infrared spectroscopy, scanning electron microscopy and energy‐dispersive X‐ray spectroscopy. The average particle size using Scherrer's equation was calculated to be below 50 nm.

Crystal exploring, Hirshfeld surface analysis, and properties of 4′‐(furan‐2‐yl)‐2,2′:6′,2″‐terpyridine complexes of nickel (II): New precursors for the synthesis of nanoparticles

“…The IR spectra of NiO NPs 3a ‐ b and 4a ‐ b show the characteristic bands about 434–514 cm −1 , which have been assigned to the Ni–O bonds stretching mode. [ 7 ] The IR spectrum of 3a displays a strong band at 483 cm −1 and corresponds to the vibration of Ni–O bond (Figure S7). The appearance of a band at 1120 cm −1 has been assigned to the symmetric stretching of SO 4 2− groups of K 2 SO 4 as an impurity.…”

“…[ 1–6 ] Accordingly, terpyridine and its derivatives with plentiful potential application are important ligands for constructing metal complexes. [ 7,8 ] Specifically, platinum (II) terpyridine complexes as planar intercalators have been researched in recent years due to their promising biological activities such as DNA binding agents and antitumor agents. [ 9 ] For example, platinum (II) complex of 4′‐pyridyl functionalized −2,2′:6′,2″‐terpyridines was found to have cytotoxicity effect higher than cisplatin.…”

“…The PF 6 − has been used as a counterion in order to obtain better single crystals, and SCN − as a bidentate ligand was used to investigate its ability to form mixed thiocyanato complexes or act as a bridging ligand. [ 4,7,8 ] Moreover, the thermal behavior and fluorescence properties of the Ni (II) complexes have been studied, and application of them as new precursors for the preparation of nickel phosphate and nickel oxide NPs was studied.…”

Anion-Controlled Assembly of a Silver-Responsive Bifunctional Coordination Polymer with Detection and Large Adsorption Capacity

“…Therefore, the ligand in 4 is adopted through type III coordination, resulting in a 2D 3,4-connected bex topology. Thus, when utilizing different anions and the flexibility of different polyazole moieties, the crystal structure can be altered, and interesting results can be obtained. , …”

“…Especially, intermolecular interactions of chlorine in 4 are different, Cl···Cl = 6.9% and Cl···H = 26.7%. Consequently, Cl has plenty of room to collaborate with Ag­(I). , …”