New Triphenylamine-Based Oligomeric Schiff Bases Containing Tetraphenylsilane Moieties in the Backbone

Excellent removal performance of 4,4'-biphenyldicarboxaldehyde m-phenylenediamine Schiff base magnetic polymer towards phenanthrene and 9-phenanthrol: Experimental, modeling and DFT calculations studies

Phenanthrene (PTH) and 9-phenanthrol (9-PTH) exhibited severe health threats and ecological hazards, for this reason, exploring a high-efficient removing strategy for PTH and 9-PTH could be considered of great urgency. Herein the 4,4'-biphenyldicarboxaldehyde m-phenylenediamine Schiff base magnetic polymer (magnetic BIPH-PHEN) was successfully fabricated via Schiff base polycondensation reaction and the subsequently one-pot embedded method. The mutual aromatic nucleus of BIPH-PHEN polymer and PTH/9-PTH could form π-π interaction, thus improving the capture ability, the embedded Fe₃O₄ nanoparticles provided the possibility for rapid separation. The physical and chemical properties of the magnetic BIPH-PHEN were systematically characterized. The removal rate of magnetic BIPH-PHEN towards PTH and 9-PTH was 85.65 % and 98.52 %, respectively (PTH or 9-PTH: 8 mg/L; Adsorbent: 0.2 g/L). The DFT calculations including energy calculations and electrostatic potential distribution analyzed the different bonding modes and proposed the most possible bonding modes in the adsorbent/adsorbate system. Moreover, the LUMO and HOMO orbits combined with energy gaps analysis proved the existence and specific types of the π-π interaction. The monolayer adsorption occurred on the homogeneous magnetic BIPH-PHEN surface, simultaneously the chemisorption was dominant. This work not only proposed new sights on assembling magnetic Schiff base polymer for removing polycyclic aromatic hydrocarbons, but also provided a deeper understanding of intramolecular interactions.

2-methoxy-4-(((5-nitropyridin-2-yl)imino)methyl)phenol Schiff base ligand and its Cu(II) and Zn(II) complexes: synthesis, characterization and biological investigations

In this current work we have prepared a Schiff base ligand, (HL) derived from 5- nitropyridine-2-amine with 4-hydroxy-3-methoxybenzaldehyde and its Cu(II), and Zn(II) in 2:1 stoichiometric ratio (2HL:M). The formation of the ligand and the metal complexes were evaluated by means of MS, FT-IR, UV-Visible, ¹H-NMR, ¹³C-NMR and thermogravimetric methods. The free radical scavenging activity of compounds was evaluated through a sequence of in vitro assays viz., DPPH, ABTS and Superoxide where BHA was used as a positive controller. In vitro α-glucosidase inhibitory activities showed that complexes had considerable inhibitory potential when compared to the ligand.

Conjugation-broken thiophene-based electropolymerized polymers with well-defined structures: effect of conjugation lengths on electrochromic properties

The present work highlights the links between electrochromic properties and conjugation-broken thiophene polymers with well-defined structures.

Synthesis, characterization and solid state conductivity of nano-size ionic Schiff base polymers of Cu2+, Zn2+ and VO2+ containing viologen moieties

The new nano size ionic metallo-Schiff base polymers (IMSPs) were synthesized by reaction of Schiff base ligand of L and VO (acac)₂, ZnCl₂ and CuCl₂. The solid state conductivity measurements candidate them as new metallo-organic semiconductors.