Solvent Effects on the Electronic Spectra of Some Heterocyclic Azo Dyes

Behera, Pradipta Kumar; Xess, Anita; Sahu, Sachita

doi:10.5012/bkcs.2014.35.2.610

Cited by 16 publications

(2 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The effect that the absorption spectra in DMSO are shifted to lower wavenumbers to a much greater extent was previously attributed to the high propensity of DMSO to act as hydrogen‐bond acceptor resulting in the formation of hydrogen‐bonding complexes that cause an even more pronounced stabilization of the excited state . In contrast to the alkylamino‐substituted azothiazoles 7 a‐ ‐ c , the absorption maxima of 7 d and 8 a‐ ‐ c do not correlate well with the dipolarity (Figure S4 B–E) or any other particular solvent property.…”

Section: Discussionmentioning

confidence: 79%

Synthesis of 5‐Alkyl‐ and 5‐Phenylamino‐Substituted Azothiazole Dyes with Solvatochromic and DNA‐Binding Properties

Pithan

Kuhlmann

Engelhard

et al. 2019

Chemistry A European J

View full text Add to dashboard Cite

A series of new 5‐mono‐ and 5,5′‐bisamino‐substituted azothiazole derivatives was synthesized from the readily available diethyl azothiazole‐4,4′‐dicarboxylate. This reaction most likely comprises an initial Michael‐type addition by the respective primary alkyl and aromatic amines at the carbon atom C5 of the substrate. Subsequently, the resulting intermediates are readily oxidized by molecular oxygen to afford the amino‐substituted azothiazole derivatives. The latter exhibit remarkably red‐shifted absorption bands (λabs=507–661 nm) with high molar extinction coefficients and show a strong positive solvatochromism. As revealed by spectrometric titrations and circular and linear dichroism studies, the water‐soluble, bis‐(dimethylaminopropylamino)‐substituted azo dye associates with duplex DNA by formation of aggregates along the phosphate backbone at high ligand–DNA ratios (LDR) and by intercalation at low LDR, which also leads to a significant increase of the otherwise low emission intensity at 671 nm.

show abstract

Section: Discussionmentioning

confidence: 79%

Synthesis of 5‐Alkyl‐ and 5‐Phenylamino‐Substituted Azothiazole Dyes with Solvatochromic and DNA‐Binding Properties

Pithan

Kuhlmann

Engelhard

et al. 2019

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…Various organic compounds' solvatochromism is used to define 𝜋*, which refers to polarity, 𝛼 and 𝛽, which represent their ability to behave as hydrogen bond donor or acceptor. The physical intramolecular solute-solvent interaction forces tend to affect the energy difference between ground and excited states of the absorbing species containing the chromophore, resulting in a shift in spectra and absorption when using organic solvents compared to water 33 . Table 1 illustrates the effect of different organic solvents on the spectrum of the dye formed.…”

Section: Influences Various Organic Solventsmentioning

confidence: 99%

Spectrophotometric Method Combined with HPLC for Bisphenol F Determination in Plastic Bottled Water and Thermal Paper

Habib,

Al-Tameemi,

Tofah

et al. 2023

Baghdad Sci.J

View full text Add to dashboard Cite

Based on the diazotization-coupling reaction, a new, simple, and sensitive spectrophotometric method for determining of a trace amount of (BPF) is presented in this paper. Diazotized metoclopramide reagent react with bisphenol F produces an orange azo-compound with a maximum absorbance at 461 nm in alkaline solution. The experimental parameters were optimized such as type of alkaline medium, concentration of NaOH, diazotized metoclopramide amount, order additions, reaction time, temperature, and effect of organic solvents to achieve the optimal performance for the proposed method. The absorbance increased linearly with increasing bisphenol F concentration in the range of 0.5-10 μg mL -1 under ideal conditions, with a correlation coefficient of 0.9931 and a detection limit of 0.15 μg mL -1 . The effect of different temperatures and different extraction time was studied on the leaching out and the data indicates that as time and temperature rising, the concentration of BPF leached out of all thermal papers increased. To confirm that extracts from thermal papers contained BPF, samples containing the analytic were subjected to high-performance liquid chromatography (HPLC-UV detector) analysis. The analysis was carried out on a C18 column with a mobile phase of acetonitrile/water (55/45v:v), and the detection was conducted spectrophotometrically at 230 nm. The retention time of standard BPF was determined to be 5.649 min and the peak eluting time for most thermal papers extract was at 5.6 minutes, demonstrating that BPF was present in the thermal papers. The method was applied to quantify the proposed analyses in a variety of samples with excellent results.

show abstract

Photoswitchable Rhodamine‐Based Multianalyte Sensors for Metal Ion Detection

Srivastava,

Grewal,

Singh

et al. 2023

ChemPhotoChem

View full text Add to dashboard Cite

We have developed three azobenzene‐core‐based molecular systems decorated with different numbers of rhodamine units as photoswitchable multianalyte sensors. Exploiting the ring‐opening of the spirolactam part of the rhodamine unit, the resulting fluorescence response, and modulation of it through the photoswitching of azobenzene by light, we utilized them in the detection of multiple metal ions (Fe3+, Fe2+, Sn2+ and Al3+). The binding sites, stoichiometry, binding constants, fluorescent lifetimes and limit of detection (LOD) for each probe have been deduced using appropriate spectroscopic techniques. The limit of detection (LOD) of 5 a, 5 b and 5 c for Fe3+ are found to be 4.2×10−7±7.8×10−9 M, 2.2×10−7±4.6×10−9 M and 1.2×10−7±4.6×10−9 M, respectively. The fluorescence response of the metal‐chelated complex can be manipulated effectively by employing the photoswitching ability of azobenzene that makes them useful as chemosensors for various individual metal ions.

show abstract

Solvent Effects on the Electronic Spectra of Some Heterocyclic Azo Dyes

Cited by 16 publications

References 28 publications

Synthesis of 5‐Alkyl‐ and 5‐Phenylamino‐Substituted Azothiazole Dyes with Solvatochromic and DNA‐Binding Properties

Synthesis of 5‐Alkyl‐ and 5‐Phenylamino‐Substituted Azothiazole Dyes with Solvatochromic and DNA‐Binding Properties

Spectrophotometric Method Combined with HPLC for Bisphenol F Determination in Plastic Bottled Water and Thermal Paper

Photoswitchable Rhodamine‐Based Multianalyte Sensors for Metal Ion Detection

Contact Info

Product

Resources

About