Optical and electrochemical properties of novel thermally stable Schiff bases bearing naphthalene unit

Sęk, Danuta; Siwy, Mariola; Bijak, Katarzyna; Filapek, Michał; Małecki, Jan Grzegorz; Nowak, E.; Sanetra, J.; Jarczyk-Jedryka, Anna; Łaba, Katarzyna; Łapkowski, Mieczysław; Schab‐Balcerzak, Ewa

doi:10.1016/j.jelechem.2015.05.040

Cited by 23 publications

(8 citation statements)

References 34 publications

(31 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…= not isolated (some reactants and/or imine were still present in the crude); f Liquid Assisted Grinding conditions (LAG) using EtOH (100 L,  = 0.17), with  value 44 defined as the volume of the solvent (in μL) / the sample weight (in mg). However, 31 P NMR analyses of the crude mixtures after 4 hour milling indicated the presence of unreacted diethylphosphite ppm): 7.34 ppm in CDCl 3  while 1 H NMR spectra clearly showed the full conversion of benzaldehyde and the amine, in favor of the selective and almost quantitative formation of the corresponding E-imines E-1 45 and E-2 [46][47] (Table 1, entries 1a and 1b respectively). The recovery of pure solid E-imines E-1 and E-2 was straightforward: water was added directly into the jar, followed by the filtration of the precipitate and drying under vacuo over MgSO 4 , while the unreacted liquid diethylphosphite and/or its hydrolysed counterpart were easily eliminated in the water phase.…”

Section: Resultsmentioning

confidence: 99%

Kabachnik–Fields Reaction by Mechanochemistry: New Horizons from Old Methods

Fiore

Sović

Lukin

et al. 2020

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

-Aminophosphonates are an important class of biologically active compounds, attracting considerable attention in medicinal chemistry, by inhibiting enzymes involved in amino acid metabolism. Herein, the Kabachnik-Fields domino reaction was investigated by mechanochemistry for the first-time preparation of -aminophosphonate derivatives in high yields and with full selectivity, outperforming comparable solution procedures. The reaction is a Lewis acid-catalysed process occurring however without the addition of any external catalyst, but occurring on the surface of the zirconium oxide used as the milling media. The mechanism of the mechanochemical reaction was also investigated by in situ Raman spectroscopy, the kinetic behavior was disclosed. The solid-state structures of two representative compounds have been determined by single-crystal X-ray diffractions.

show abstract

Section: Resultsmentioning

confidence: 99%

Kabachnik–Fields Reaction by Mechanochemistry: New Horizons from Old Methods

Fiore

Sović

Lukin

et al. 2020

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

show abstract

“…The bands at 230 nm and 288 nm were attributed to the π-π* transitions of the aromatic rings of pyrrole and naphthalene. The absorption band at 349 nm was attributed to the π-π* of the imine [23] ( Figure 1).…”

Section: Resultsmentioning

confidence: 99%

Metallated Schiff-Base Macromolecules as Alternative Metalloprotein Electron Transfer Intermediates

Farao¹,

Ajayi²,

Ward³

et al. 2020

JSEMAT

View full text Add to dashboard Cite

In the construction of biosensors, enzymes function as mediators converting biological signals generated by specific biological processes, into electrochemical signals. The ideology of bio-sensor design is retention of electron transfer activity of the enzyme utilizing superior interfacial architecture. In this work a Schiff-base macromolecule has been synthesized by reflux of 2, 3-diaminonaphthalene and pyrrole-2-carboxaldehyde starting materials. The Schiff-base ligand was subsequently complexed with FeCl 2 •4H 2 O under reflux, to produce the Fe-Schiff-base complex. The Schiff-base ligand and Fe-Schiff-base complex were characterized using nuclear magnetic resonance (NMR) spectroscopy, Ultra Violet/Visible (UV/Vis) spectroscopy, Fourier transfer infrared resonance (FTIR) and electron energy loss spectroscopy (EELS) to confirm the structure of the synthesis products. NMR spectroscopy confirmed the imide linkage of Schiff-base formation as two symmetrical peaks at 8.1 and 7.7 ppm respectively. Comparison of starting materials and product spectra by UV/Vis spectroscopy confirmed the disappearance of the diaminonaphthalene peak at 250 nm as evidence of complete conversion to product. FTIR spectroscopy of the Schiff-base ligand confirmed the formation of the imine bond at 1595 cm −1. EELS spectra comparing FeCl 2 •4H 2 O and the Fe-Schiff-base complex, showed good agreement in the energy loss profiles associated with changes to the electronic arrangement of Fe d-orbitals. EDS clearly identified a spectral band for Fe (7-8 eV) in the Fe-Schiff-base complex. Electrochemical evaluation of the Fe-Schiff-base complex was compared to the electrochemical signature of denatured cytochrome-C using cyclic voltammetry and square wave voltammetry. The Fe 2+ /Fe 3+ quasi-reversible behavior for iron in the metallated complex was observed at −0.430 V vs. Ag/AgCl, which is consistent with reference values for iron in macromolecular structures.

show abstract

“…The selectivity abilities of the sensor L were determined by monitoring changes of the UV-vis absorption spectra and fluorescence spectra in the presence of various metal ions (Na + , K + , Ag + , Mg 2+ , Ca 2+ , Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ , Cd 2+ , Hg 2+ , Fe 2+ , Pb 2+ , Al 3+ , Cr 3+ , Fe 3+ , La 3+ , Ce 3+ ) in the 10 μmol L -1 concentration of each component in ethanol solution (Figure 2). It could be seen from Figure 2a that the absorption spectrum of sensor L exhibited two bands at 295 nm and 382 nm, corresponding to the π-π* transition of the aromatic rings and n-π* transition of the C=N group respectively which also were supported by the formation of the sensor L. 28,29 Upon addition of Al 3+ , Fe 3+ , Cr 3+ , La 3+ and Ce 3+ ions, two significant absorption bands centered at about 250 nm and 327 nm were clearly observed, while the bands at 295 nm and 382 nm disappeared. Meanwhile, these changes were also accompanied with a nakyed-eye color variation from pale yellow to colorless after addition of Al 3+ , Fe 3+ , Cr 3+ , La 3+ and Ce 3+ ions (Figure 2a inset).…”

Section: Selectivity Studiesmentioning

confidence: 85%

A Highly Selective Fluorescent Sensor for Detection of Trivalent Metal Ions Based on a Simple Schiff-Base

Ding¹,

Zhao²

2018

Quim. Nova

View full text Add to dashboard Cite

A simple and easily synthesized fluorescent sensor L, based on condensation reaction of 1-Naphthylamine and terephthalaldehyde, was synthesized and characterized systemically. Both UV-vis and fluorescence spectroscopic studies indicated that the sensor L showed good selectivity toward trivalent metal ions (such as Al 3+ , Fe 3+ , Cr 3+ , La 3+ and Ce 3+) over other monovalent or divalent metal ions. The sensing mechanism was suggested that the trivalent ion promoted the hydrolysis of Schiff base. Meanwhile, took the common trivalent ions Al 3+ , Fe 3+ and Cr 3+ as examples, limit of detection (LOD) values of sensor L were calculated to be 1.23, 0.94 and 1.14 nM for Al 3+ , Cr 3+ and Fe 3+ , respectively, suggesting very high sensitivity towards the cations which could make it attractive in trivalent metal ions detection.

show abstract

Optical and electrochemical properties of novel thermally stable Schiff bases bearing naphthalene unit

Cited by 23 publications

References 34 publications

Kabachnik–Fields Reaction by Mechanochemistry: New Horizons from Old Methods

Kabachnik–Fields Reaction by Mechanochemistry: New Horizons from Old Methods

Metallated Schiff-Base Macromolecules as Alternative Metalloprotein Electron Transfer Intermediates

A Highly Selective Fluorescent Sensor for Detection of Trivalent Metal Ions Based on a Simple Schiff-Base

Contact Info

Product

Resources

About