Electron-donating methoxyl group position effect on properties of diarylethene derivatives having a pyrazole unit

2007 ◽  
Vol 85 (1) ◽  
pp. 12-20 ◽  
Author(s):  
Tianshe Yang ◽  
Shouzhi Pu ◽  
Bing Chen ◽  
Jingkun Xu
Keyword(s):  
Quantum Yield ◽  
Electrochemical Properties ◽  
Phenyl Ring ◽  
Position Effect ◽  
Methoxyl Group ◽  
Strong Fluorescence ◽  
First Order ◽  
Group Position

New types of asymmetrical photochromic diarylethene derivatives having a pyrazole unit, namely 1-[1,3,5-trimethyl-1-pyrazol-4-yl],2-[2-methyl-5-(4-methoxylphenyl)-1-thien-3-yl]perfluorocyclopentene (1a), 1-[1,3,5-trimethylpyrazol-4-yl],2-[2-methyl-5-(3-methoxylphenyl)-1-thien-3-yl] perfluorocyclopentene (2a), 1-[1,3,5-trimethyl-pyrazol-4-yl],2-[2-methyl-5-(2-methoxylphenyl)-1-thien-3-yl]perfluorocyclopentene (3a), and 1-[1,3,5-trimethyl-pyrazol-4-yl],2-[2-methyl-5-phenyl-1-thien-3-yl]perfluorocyclopentene (4a), were synthesized. Their optical and electrochemical properties, such as photochromism, photochromic cyclization–cycloreversion kinetics, and fluorescence and electrochemical properties were investigated in detail. The results show that all of these compounds have good photochromism, high cycloreversion quantum yield, and relatively strong fluorescence. Their cyclization-cycloreversion processes were determined to be zeroth to first order reactions. The oxidations of diarylethenes 1a–4a were initiated at 0.73, 1.11, 0.79, and 1.03 V, respectively. Furthermore, introduction of the electron-donating methoxyl group at different positions of the terminal phenyl ring was found to strongly influence these optical and electrochemical properties.Key words: photochromism, diarylethene, electron-donating group, optical and electrochemical properties.

Photochromism of a New Unsymmetrical Diarylethene Bearing both Thiazole and a Methoxyl Group

2011 ◽  
Vol 295-297 ◽  
pp. 228-231
Author(s):  
Hui Li ◽  
Shou Zhi Pu ◽  
Shi Qiang Cui
Keyword(s):  
Cyclic Voltammetry ◽  
Electrochemical Properties ◽  
Benzene Ring ◽  
Phenyl Ring ◽  
Methoxyl Group ◽  
Pmma Film ◽  
Isomeric Compound ◽  
Fluorescence Switch

A new unsymmetrical isomeric diarylethene bearing an electron-donating methoxyl group atortho-positions of the terminal phenyl ring was synthesized, namely 1-(2,4-dimethyl-5-thiazolyl) -2-[2-methyl-5-(2-methoxyphenyl)-3-thienyl]perfluorocyclopentene (1o). The compound displayed excellent photochromism both in solution and in PMMA film. The isomeric compound also functioned as a fluorescence switch by photoirradiation in solution. In addition, cyclic voltammetry tests showed that the electron-donating methoxyl group at the terminal benzene ring had a significant effect on the electrochemical properties of the isomeric diarylethene.

Synthesis, Properties and Application in Optical Memory of a Novel Photochromic Diarylethene Bearing an Anthracene Ring

2011 ◽  
Vol 399-401 ◽  
pp. 1055-1058
Author(s):  
Shang Hua He ◽  
Gang Liu ◽  
Shi Qiang Cui
Keyword(s):  
Optical Memory ◽  
Order Reaction ◽  
Photochromic Properties ◽  
Strong Fluorescence ◽  
First Order ◽  
Cyclization Process ◽  
Open Ring ◽  
Synthesis Properties ◽  
Photochromic Reaction ◽  
Hexane Solution

In the present study, we designed a novel unsymmetrical isomeric diarylethene derivative bearing both thiophene and anthracene moieties. Its photochromic properties and fluorescence were investigated in detail. In hexane solution, the open-ring isomer of the diarylethene 1 exhibited relatively strong fluorescence. The photochromic reaction kinetics indicated that the cyclization process of 1o belongs to the zeroth order reaction and the cycloreversion process belongs to the first order reaction. This new photochromic system also exhibited remarkable optical storage character.

The Influence of Amino Group Position on Aryl Moiety of SarAr on Metal Complexation and Protein Labelling

2016 ◽  
Vol 69 (9) ◽  
pp. 1054 ◽  
Author(s):  
Vincent Jamier ◽  
Eskender Mume ◽  
Cyril Papamicaël ◽  
Suzanne. V. Smith
Keyword(s):  
Bovine Serum Albumin ◽  
Ambient Temperature ◽  
Bovine Serum ◽  
Phenyl Ring ◽  
Metal Complexation ◽  
Molar Ratio ◽  
Amino Group ◽  
Fundamental Study ◽  
Group Position ◽  
Ph Range

New hexaazamacrobicyclic cage bi-functional chelators (BFCs), 1-N-(3-aminobenzyl)-3,6,10,13,16,19-hexaazabicyclo[6.6.6]eicosane-1,8-diamine (m-SarAr) and 1-N-(2-aminobenzyl)-3,6,10,13,16,19-hexaazabicyclo[6.6.6]eicosane-1,8-diamine (o-SarAr), were synthesised. Their complexation with selected transitions metal ions i.e. CuII, CoII, and CdII was investigated over a range of pH at micromolar concentrations. CuII was complexed by m-SarAr and o-SarAr rapidly within 5 min in pH range of 5–9 at ambient temperature. In contrast, the complexation of CoII and CdII by these ligands was slower. The conjugation efficiencies of p-SarAr, m-SarAr, and o-SarAr to bovine serum albumin (BSA) were compared under various reactions. Conditions were optimised to a molar ratio of BSA/N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide (EDC)/BFC of 1 : 250 : 50 in pH 5 buffer for 30 min at ambient temperature. Under these conditions, the average number of p-SarAr, m-SarAr, or o-SarAr attached to BSA were determined to be 2.21 ± 0.16, 4.90 × 10–1 ± 2.48 × 10–2, and 2.67 × 10–2 ± 2.67 × 10–3, respectively. This fundamental study clearly demonstrates that the position of the amine on the phenyl ring has a significant effect on the metal complexation and conjugation reactions with BSA.

Magnesium(ii) 1-(1-adamantylsulfanyl)phthalocyanine – synthesis, photochemical and electrochemical properties

2016 ◽  
Vol 40 (11) ◽  
pp. 9774-9780 ◽  
Author(s):  
Michal Kryjewski ◽  
Tomasz Rebis ◽  
Grzegorz Milczarek ◽  
Zofia Gdaniec ◽  
Tomasz Goslinski ◽  
...  
Keyword(s):  
Quantum Yield ◽  
Singlet Oxygen ◽  
Electrochemical Properties

Phthalocyanine with moderate fluorescence and singlet oxygen quantum yield was obtained and its electrochemical properties were assessed.

Synthesis, and Properties of 1-[2-methyl-5-(1,3-difluorophenyl)-3-thienyl]-2-[2-methyl-5-(4-methoxylphenyl)-3-thienyl]perfluorocyclopentene

2014 ◽  
Vol 952 ◽  
pp. 88-91
Author(s):  
Zhao Yan Tian ◽  
Feng Xia Sun ◽  
Shou Zhi Pu
Keyword(s):  
Visible Light ◽  
Phenyl Ring ◽  
Uv Light ◽  
Maximum Absorption ◽  
Methoxyl Group ◽  
Pmma Film ◽  
Ring Form ◽  
Hexane Solution

A new unsymmetrical photochromic diarylethene 1-[2-methyl-5-(1,3-difluorophenyl)-3-thienyl]-2-[2-methyl-5-(4-methoxylphenyl)-3-thienyl] perfluorocyclopentene has been synthesized,which a methoxyl group was substituted at the para-positions of the terminal phenyl ring. The photochromism of this compound was investigated, the results showed that this compound exhibited reversible photochromism, inducing cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light both in solution and in a PMMA film. When irradiated 297 nm UV light, in hexane solution the maximum absorption was observed at 289 nm and 588 nm in opening-ring form and in close-ring form, respectively.

PHOTOCHROMIC KINETICS OF ASYMMETRICAL DIARYLETHENES IN DIFFERENT SOLVENTS AND IN PMMA FILMS

2008 ◽  
Vol 15 (01n02) ◽  
pp. 145-151 ◽  
Author(s):  
MIN LI ◽  
SHOUZHI PU ◽  
CHUNHONG ZHENG ◽  
MINGBIAO LUO ◽  
ZHANGGAO LE
Keyword(s):  
Position Effect ◽  
Phenyl Group ◽  
Solvent Polarity ◽  
Reaction Rates ◽  
Order Reaction ◽  
Para Position ◽  
First Order Reaction ◽  
First Order ◽  
Kinetics Of

Three new asymmetric photochromic diarylethenes bearing fluorine atoms at the ortho-, meta-, or para-position of one terminal phenyl group were synthesized, and their photochromism and kinetics of the photochromic cyclization/cycloreversion both in different solvents and in PMMA films were investigated. The results showed that the cyclization/cycloreversion process of these compounds were determined to be zeroth/first order reaction, and the reaction rates (k) were obtained from the slope of every line. The substituent position effect on the cycloreversion process of the three compounds was remarkable and the solvent polarity enhanced this effect. The values of reaction rates in PMMA films were quite different from those in solvents indicating that the kinetics processes of the three compounds taking place in PMMA films differs from the same processes occurring in common solvent.

Photocatalytic degradation of dye pollutants in the presence of acetone

2001 ◽  
Vol 44 (6) ◽  
pp. 173-180 ◽  
Author(s):  
S.-M. Tsui ◽  
W. Chu
Keyword(s):  
Quantum Yield ◽  
Critical Factor ◽  
Reactive Dye ◽  
Optimum Conditions ◽  
Decay Kinetics ◽  
Triplet Energy ◽  
First Order ◽  
Dye Pollutants ◽  
Initial Ph ◽  
Reactive Red 2

The photodegradation of textile azo dyes in aqueous solution containing acetone (ACE) photosensitizer was investigated at 253.7 nm. In this study, a typical azo reactive dye (C I Reactive Red 2 - RR2) is used as the probe compound. ACE is a powerful photosensitizer that possesses high triplet energy, and the presence of ACE significantly enhances the overall photodegradation reaction through simultaneous sensitization. In the UV/ACE system, at the optimum conditions, over 97% of RR2 can be successfully decomposed and decolored within 300 seconds of retention time. The photodegradation mechanisms of RR2 involve both photodechlorination and photoreduction, which follow pseudo first-order decay kinetics. The quantum yield of the photolysis system has been evaluated as a function of ACE concentration and the initial pH. RR2 contains the chlorotriazinyl group, which undergoes hydrolysis and results in the formation of hydrochloric acid, indicating that the photodechlorination process is the dominant reaction mechanism. The photo-product, H+, is likely to retard the quantum yield of dye decay, suggesting that the initial pH is a critical factor in changing the photodecolorization rates of dye. Generally, this system is more favorable at higher pH levels.

scholarly journals Phenylcarbamic acid derivatives with integrated n-phenylpiperazine moiety in the structure – kinetics of alkaline hydrolysis study / Deriváty kyseliny fenylkarbámovej s integrovanou n-fenylpiperazínovou zložkou v štruktúre – štúdium kinetiky alkalickej hydrolýzy

2015 ◽  
Vol 62 (2) ◽  
pp. 38-42
Author(s):  
Stankovičová M. ◽  
Miháliková V. ◽  
Mezovský Ľ. ◽  
Lašáková A. ◽  
Medlenová V. ◽  
...  
Keyword(s):  
Alkaline Hydrolysis ◽  
Phenyl Ring ◽  
Arrhenius Equation ◽  
Sodium Hydroxide Solution ◽  
Antimycobacterial Activity ◽  
First Order ◽  
Rate Of Hydrolysis ◽  
Pseudo First Order ◽  
Kinetics Of ◽  
Hydrolysis Of

AbstractIn present work, we have studied kinetics of alkaline hydrolysis of 14 compounds, which are phenylcarbamic acid derivatives with integrated N-phenylpiperazine moiety in the structure. The compounds possessed moderate antiarrhythmic and antimycobacterial activity. Their hydrolysis was carried out in an aqueous medium ethanol sodium hydroxide solution. The course of the hydrolysis was observed spectrophotometrically in visible as well as in ultraviolet regions. The pseudo-first order rate constants were calculated at several temperatures. The values of the activation energy EAwere determined by the Arrhenius equation. The rate of hydrolysis of the compounds under the study increase with the increase in temperature and it has been differentiated according to the substitution of N-phenylpiperazine as well as to the alkoxy substitution on phenyl ring.

Synthesis and Application of Photochromic Materials in Holographic Recording of a Asymmetrical Diarylethene

2013 ◽  
Vol 763 ◽  
pp. 88-92 ◽  
Author(s):  
Ren Jie Wang ◽  
Pan Pan Ren ◽  
Shi Qiang Cui ◽  
Shou Zhi Pu
Keyword(s):  
Phenyl Ring ◽  
Methoxy Group ◽  
Uv Light ◽  
Optical Recording ◽  
Holographic Recording ◽  
Pmma Film ◽  
Photochromic Properties ◽  
Strong Fluorescence ◽  
Open Ring ◽  
Photochromic Materials

A novel unsymmetrical diarylethene derivative containing thiophene moieties, in which a methoxy group was substituted at the para-positions of the terminal phenyl ring, was synthesized. Its photochromic properties were investigated in detail, the results indicated that the diarylethene 1o changed the color from colorless to blue, which the absorption maxima were observed at 611 and 627 nm in hexane and PMMA film when irradiation with 297 nm UV light. Additionally, the open-ring isomer of the diarylethene 1o exhibited relatively strong fluorescence at 305 nm in hexane when excited at 322 nm and the fluorescence intensity progressively decreased accompany with the photocyclization occurs. Finally, using this diarylethene as recording medium, polarization optical recording was carried out successfully.

scholarly journals Kinetics and Mechanism of the Photochromism of N-Phenyl-Rhodaminelactame

1989 ◽  
Vol 10 (2) ◽  
pp. 63-72 ◽  
Author(s):  
H. Willwohl ◽  
J. Wolfrum ◽  
R. Gleiter
Keyword(s):  
Quantum Yield ◽  
Picosecond Laser ◽  
Laser Pulses ◽  
Laser Flash ◽  
Time Resolved ◽  
First Order ◽  
First Order Kinetics ◽  
Relative Quantum ◽  
Millisecond Time Scale ◽  
Resolution Single

The photochromism of N-phenyl-rhodaminelactame (3' ,6' -bis-(diethylamino)-2-phenyl-spiro[1H-isoindole-1,9'[9H] Xanthaen]-3-[2H]-one) was investigated in solutions of acetonitrile, dioxane and mixtures of dioxane with H20, methanol and ethanol by laser flash time resolved absorption measurements. The colouring reaction kinetics and the relative quantum yield of the red product were measured using nanosecond excimer laser excitation at 308 nm. In most cases, first order kinetics was.observed. The first order rate constants and the quantum yield were found to be dependent on the solvent and the number of laser pulses that had previously irradiated the solution. The thermal fading reaction occurred on a millisecond timescale and showed large deviations from first order kinetics in all solvents. In addition, picosecond laser pulses at 285 nm were used to measure the fluorescence lifetime of the S1 state of the rhodamine derivative with picosecond resolution. Single exponential decays were observed in all solvents and the lifetime ranged between 3 and 6 nanoseconds. We conclude that the photoreaction does not proceed directly from the S1 state, and propose a mechanism for the photochromic process, in which an intermediate decomposes to rotameric isomers of the coloured product, which are not equilibrated on the millisecond time scale of the reverse reaction.

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