Bis(diarylethenyl)-thiophenes, -bithiophenes, and -terthiophenes: a new series of electrochromic systems that exhibit a fluorescence response

2,5-Bis(diarylethenyl)thiophenes (1) and their bithiophene (2) and terthiophene (3) homologues were designed as a new series of violene/cyanine-hybrid-type electrochromic materials. Alkoxyphenyl and dialkylaminophenyl groups are used as the aryl group in the cyanine parts of 1/2/3O and 1/2/3N, respectively, which emit fluorescence in the neutral state but not in the oxidized state. Voltammetric analyses of 18 newly prepared electron donors show that they all undergo two reversible one-electron oxidations. Redox potentials, UV–vis spectral features, and fluorescence quantum yields are important parameters for characterizing the present electrochromic behavior with a fluorescence response, and can be finely tuned by changing aryl groups in the cyanine part, the number of thiophene rings in the violene part, and the alkyl-chain length of the alkoxyphenyl or diaklylaminophenyl groups (R = CH3, C8H17, C16H33), which makes this a versatile platform for the design of novel electrochromic materials.

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The Effect of Varying Short-Chain Alkyl Substitution on the Molar Absorptivity and Quantum Yield of Cyanine Dyes

Analytical Chemistry Insights ◽

10.4137/aci.s6568 ◽

2011 ◽

Vol 6 ◽

pp. ACI.S6568 ◽

Cited By ~ 23

Author(s):

Gala Chapman ◽

Maged Henary ◽

Gabor Patonay

Keyword(s):

Quantum Yield ◽

Alkyl Chain ◽

Cyanine Dyes ◽

Spectroscopic Properties ◽

Molar Absorptivity ◽

Alkyl Chain Length ◽

Short Chain ◽

Quantum Yields ◽

Fluorescence Quantum Yields ◽

Alkyl Substitution

The effect of varying short-chain alkyl substitution of the indole nitrogens on the spectroscopic properties of cyanine dyes was examined. Molar absorptivities and fluorescence quantum yields were determined for a set of pentamethine dyes and a set of heptamethine dyes for which the substitution of the indole nitrogen was varied. For both sets of dyes, increasing alkyl chain length resulted in no significant change in quantum yield or molar absorptivity. These results may be useful in designing new cyanine dyes for analytical applications and predicting their spectroscopic properties.

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Synthesis of A2B-type 22-oxacorroles bearing two different five-membered heterocycles at meso positions

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s108842461950144x ◽

2020 ◽

Vol 24 (01n03) ◽

pp. 432-439

Author(s):

Umasekhar Booruga ◽

Mangalampalli Ravikanth

Keyword(s):

2D Nmr ◽

Quantum Yields ◽

Electrochemical Studies ◽

2D Nmr Spectroscopy ◽

Nmr Studies ◽

Absorption Bands ◽

Aryl Group ◽

Fluorescence Quantum Yields ◽

Acid Catalyzed ◽

Mild Acid

A series of 22-oxacorroles containing mixed substituents such as either two five-membered heterocycles and one six-membered aryl group or three five-membered heterocycles at three meso positions were synthesized by 3 + 2 oxidative coupling of appropriate 16-oxatripyrrane and meso-substituted dipyrromethane under mild acid catalyzed conditions. The identities of the 22-oxacorroles were confirmed by the respective molecular ion peaks in HR-MS spectra and the structures were deduced by detailed 1D and 2D NMR spectroscopy. NMR studies clearly showed upfield or downfield shifts of core pyrrole and furan protons and inner NH protons depending on the type of substituent present at the meso positions. All 22-oxacorroles absorb in the 410–655 nm region, and the position of the absorption bands depends on the type of meso substituents. The A2B oxacorroles showed one broad and weak fluorescence band in the 600–700 nm region with low fluorescence quantum yields in the 0.05–0.12 range. Electrochemical studies revealed that the A2B-type 22-oxacorroles are easier to oxidize and also easier to reduce than triphenyl 22-oxacorroles. Thus, the electronic properties of 22-oxacorroles were significantly altered when six-membered aryl groups were replaced with five-membered heterocycles as reflected in spectral and electrochemical measurements.

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Synthesis and investigation of BODIPYs with restricted meso-8-aryl rotation

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424619501967 ◽

2020 ◽

Vol 24 (05n07) ◽

pp. 869-877

Author(s):

Guanyu Zhang ◽

Maodie Wang ◽

Caroline Ndung’U ◽

Petia Bobadova-Parvanova ◽

Frank R. Fronczek ◽

...

Keyword(s):

Dihedral Angle ◽

Quantum Yields ◽

Methyl Groups ◽

Free Rotation ◽

Aryl Group ◽

Chlorine Atoms ◽

Aryl Ring ◽

X Ray ◽

Fluorescence Quantum Yields ◽

High Fluorescence

Three BODIPYs bearing 1,3,5,7-tetramethyl substituents and a meso-8-aryl group were synthesized and investigated, both experimentally and computationally. The presence of the 1,7-methyl groups and of ortho-substituents on the meso-8-aryl ring prevent free rotation of the meso-8-aryl group, resulting in high fluorescence quantum yields. Substitution at the 2,6-positions of these BODIPYs with chlorine atoms causes pronounced red-shifted absorptions and emissions, and in the case of 2,6-dichloro-1,3,5,7-tetramethyl-8-(2,4,6-triphenylphenyl)-BODIPY 2c increases its fluorescence quantum yields to 0.93 in dichloromethane and 0.98 in toluene. The X-ray structure of 1,3,5,7-tetramethyl-8-(2,4,6-triphenylphenyl)-BODIPY shows increased deviation from planarity and smaller dihedral angle of the meso-8-aryl group compared with the meso-8-phenyl- and meso-8-mesityl-BODIPY analogs. The presence of 2,6-chlorine atoms was found to not significantly affect the rotational barriers of the meso-8-aryl-groups.

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Photochromic properties of six 5-O-n-alkyl,6′-CN substituted spironaphthoxazines

International Journal of Photoenergy ◽

10.1155/s1110662x0400025x ◽

2004 ◽

Vol 6 (4) ◽

pp. 199-204 ◽

Cited By ~ 8

Author(s):

A. V. Metelitsa ◽

J. C. Micheau ◽

S. O. Besugliy ◽

E. B. Gaeva ◽

N. A. Voloshin ◽

...

Keyword(s):

Alkyl Chain ◽

Bathochromic Shift ◽

Solvent Polarity ◽

Uv Spectra ◽

Alkyl Chain Length ◽

Methanol Solution ◽

Quantum Yields ◽

Photochromic Properties ◽

Numerical Fitting ◽

Visible Spectra

The photochromic properties of a series of six 5-O-n-alkyl,6′-CN substituted spironaphthoxazines has been investigated in toluene and methanol solution. The6′-CN and 5-O-n-alkyl substitutions lead to a bathochromic shift of the UV spectra of the closed forms. Theλmaxof the visible spectra of the open forms decrease with solvent polarity. Most of the photochromic parameters have been quantitatively determined. Among them, photocoloration and photobleaching quantum yields and molar absorption coefficients of the open forms have been derived from a numerical fitting of the photokinetic curves recorded under continuous monochromatic irradiation. Results show that the photo-steady-state properties are relatively independent of the 5-O-n-alkyl chain length, but are more sensitive to the size of the indolinic nitrogen substituent.

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Influence of alkyl chain length on the action of acetylated monoglycerides as plasticizers for poly (vinyl chloride) food packaging film

Food Packaging and Shelf Life ◽

10.1016/j.fpsl.2020.100619 ◽

2021 ◽

Vol 27 ◽

pp. 100619

Author(s):

Chang Woo Kwon ◽

Pahn-Shick Chang

Keyword(s):

Chain Length ◽

Vinyl Chloride ◽

Food Packaging ◽

Alkyl Chain ◽

Alkyl Chain Length ◽

Packaging Film ◽

Poly Vinyl Chloride

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Silver Nanoparticles Stabilized with Phosphorus-Containing Heterocyclic Surfactants: Synthesis, Physico-Chemical Properties, and Biological Activity Determination

Nanomaterials ◽

10.3390/nano11081883 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1883

Author(s):

Martin Pisárčik ◽

Miloš Lukáč ◽

Josef Jampílek ◽

František Bilka ◽

Andrea Bilková ◽

...

Keyword(s):

Silver Nanoparticles ◽

Biological Activity ◽

Zeta Potential ◽

Chain Length ◽

Alkyl Chain ◽

Chemical Properties ◽

Alkyl Chain Length ◽

Microbial Pathogens ◽

Physico Chemical ◽

Phosphorus Containing

Phosphorus-containing heterocyclic cationic surfactants alkyldimethylphenylphospholium bromides with the alkyl chain length 14 to 18 carbon atoms were used for the stabilization of silver nanodispersions. Zeta potential of silver nanodispersions ranges from +35 to +70 mV, which indicates the formation of stable silver nanoparticles (AgNPs). Long-chain heptadecyl and octadecyl homologs of the surfactants series provided the most intensive stabilizing effect to AgNPs, resulting in high positive zeta potential values and smaller diameter of AgNPs in the range 50–60 nm. A comparison with non-heterocyclic alkyltrimethylphosphonium surfactants of the same alkyl chain length showed better stability and more positive zeta potential values for silver nanodispersions stabilized with heterocyclic phospholium surfactants. Investigations of biological activity of phospholium-capped AgNPs are represented by the studies of antimicrobial activity and cytotoxicity. While cytotoxicity results revealed an increased level of HepG2 cell growth inhibition as compared with the cytotoxicity level of silver-free surfactant solutions, no enhanced antimicrobial action of phospholium-capped AgNPs against microbial pathogens was observed. The comparison of cytotoxicity of AgNPs stabilized with various non-heterocyclic ammonium and phosphonium surfactants shows that AgNPs capped with heterocyclic alkyldimethylphenylphospholium and non-heterocyclic triphenyl-substituted phosphonium surfactants have the highest cytotoxicity among silver nanodispersions stabilized by the series of ammonium and phosphonium surfactants.

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