Electrochemical and liquid crystal properties of ferrocene-based β-diketonato copper(II) and zinc(II) complexes

Abstract

Heterometallic liquid crystals are of special interest because of the possibility to combine optical, magnetic and electric properties of different metal ions in one mesogenic molecule. In order to investigate new heteropolynuclear mesogenic systems, the long-chain alkyl bromophenyl ferrocenyl b-diketones and their copper(II) and zinc(II) complexes were synthesized and characterized. The X-ray crystal structure reveals that b-diketone ligands exist in the enol isomer form in the crystals. These compounds exhibited good absorption and electrochemical properties. The complexes showed high thermal stability. According to thermal polarizing microscopy and differential scanning calorimetry studies, all complexes display liquid crystal behaviours. The zinc(II) complexes display lower melting point and clear point as well as a wide mesophase range compared with the copper(II) complexes. The obtained metallomesogens are important footsteps toward the development of liquid crystal materials possessing heteropolynuclear, good redox activity and chemically stable ferrocene unit.

Ferrocene and [3]ferrocenophane-based β-diketonato copper(ii) and zinc(ii) complexes: synthesis, crystal structure, electrochemistry and catalytic effect on thermal decomposition of ammonium perchlorate

“…This is because increased electron density on a metal centre of complex leads to a decrease in double bond character of the C]O and C]C groups. 35 The ESI-MS spectra showed [M + H] + peaks for all these complexes. In the 1 H NMR spectra, upon coordination, the downeld shied O-H enol proton vanished, and the two phenyl protons near vinylic doublet at 7.87-7.90 ppm in the ligands moved the signal to more downeld (7.90-7.94 ppm in the Zn(II) complexes), but the signal of other phenyl and cyclopentadienyl protons moved the signal to more upeld (by 0.03-0.06 ppm).…”

Organometallic Mesogens

“…Monosubstituted ferrocene ligands equipped with a diketonato were prepared, as well as the corresponding chelated copper(II) and zinc(II) complexes 61 (n = 8, 9, 10, 12, 14, 16). 104 The copper compounds display melting points in the range 76-106 o C and clearing points from 106 to 163 o C. On the other hand, the zinc compounds show lower melting (from 23 to 49 o C) and clearing points (from 97 to 139 o C), as well as a wider mesophase range compared with the copper derivative.…”

Liquid crystal biosensor for detecting ischemia modified albumin

“…A principle based on characteristics of the binding reaction between biological molecules that affected LC alignment for changing the polarization image was proposed. Such liquid crystal biosensors can be used for detecting cells, proteins, polypeptides, IgGs, and organic phosphorus [13][14][15]. Moreover, the LC sensor has a wide range of advantages such as simple operation, rapid response, high sensitivity, and low cost, which makes it stand out among other sensors.…”