Co-reporter:Shulei Han, Yi Chen
Dyes and Pigments 2013 Volume 96(Issue 1) pp:59-62
Publication Date(Web):January 2013
DOI:10.1016/j.dyepig.2012.03.034
N, N, N, N-tetraethyl-9H-xanthene-3,6-diamine (9H-xanthene) was prepared by one-pot reaction of 3-diethylaminophenol with (CH3O)3CH using pyridinium para-toluenesulfonate (PPTS) as catalyst. It was found that 9H-xanthene is photo-active and could be efficiently photo-converted to pyronine B. Treatment of 9H-xanthene with acid (HCl) produced protonated 9H-xanthene (9H-xanthene·HCl), and 9H-xanthene·HCl was spontaneously converted to pyronine B in aqueous solution. Besides, both distinct color change and turn on fluorescence were observed during the conversion. These findings not only provide a new and simple approach to the preparation of 9H-xanthene and pyronine B but also benefit the applications such as indicator and probe.Highlights► One-pot synthesis of N, N, N, N-tetraethyl-9H-xanthene-3,6-diamine (9H-xanthene) is developed. ► 9H-xanthene is photo-active and photo-converted to pyronine B in 80% isolated yield. ► Both distinct color change and turn on fluorescence are observed during the photo-conversion.
Co-reporter:Kunpeng Guo, Yi Chen
Materials Chemistry and Physics 2013 Volume 137(Issue 3) pp:1062-1066
Publication Date(Web):15 January 2013
DOI:10.1016/j.matchemphys.2012.11.028
Force-induced cleavage of C–O bond in photochromic naphthopyrans in the pure microcrystalline solid state is described. The ring-closed isomers (colorless form) of naphthopyrans undergo cleavage of C–O bond under stress and are converted to ring-open isomers (colored form) in solid state. It is found that the threshold stress required to produce cleavage of C–O bond in naphthopyran derivatives in pure microcrystalline solid state is more than 2 MPa. Besides, the cleavage of C–O bond in photochromic naphthopyrans in the pure microcrystalline solid state can also be achieved by grinding.Highlights► The cleavage of C–O bond in photochromic naphthopyrans in solid state is described. ► Naphthopyrans occur ring-opening reaction in solid state under stress. ► Force-induced reaction of naphthopyrans produces the same products as photo-induced. ► The threshold stress to cleave C–O bond of naphthopyrans in solid state is determined.
Co-reporter:Huan-Huan Liu, Yi Chen
Tetrahedron 2013 69(7) pp: 1872-1876
Publication Date(Web):
DOI:10.1016/j.tet.2012.12.057
Co-reporter:Xu Zhang and Yi Chen
Physical Chemistry Chemical Physics 2012 vol. 14(Issue 7) pp:2312-2316
Publication Date(Web):11 Jan 2012
DOI:10.1039/C2CP23265K
Photo-controlled metal-ion (Zn2+ and Cd2+) release in aqueous micelle solution (tris-HCl, pH = 7.4) has been described using 2-((2-mercaptophenylimino)methyl) phenol as ligand. It is found that both the ligand-Zn complex (1) and the ligand-Cd complex (2) are stable in micelle solution, and Zn2+ (Cd2+) can be released from the complex with 365 nm light trigger. Accompanying the metal-ion release, the ligand is photo-converted to 2-(benzothiazol-2-yl) phenol (3) as product, and the turn-on fluorescence is detected. The fluorescence intensity increases with the photo-triggered release until Zn2+ (Cd2+) is completely released, which is beneficial for monitoring the process of photo-controlled metal ion release. Control experiments demonstrate that no binding occurs between 3 and Zn2+ (Cd2+) in micelle solution and there is no binding between cations and micelle, either.
Co-reporter:Huan-huan Liu and Yi Chen
New Journal of Chemistry 2012 vol. 36(Issue 11) pp:2223-2227
Publication Date(Web):22 Aug 2012
DOI:10.1039/C2NJ40377C
Selective photoconversions of photochromic diarylethene derivatives has been described using diarylethene derivative 1a as a model compound. Upon irradiation with 254 nm light, 1a undergoes photocyclization to yield the ring-closed isomer 1b in the absence of oxygen, or is transformed to the thiolactone derivative 1c in the presence of oxygen (in the air), respectively. It was found that 1b can be reversed back to 1a with visible light irradiation, the ring-opening and ring-closing photoswitch can be performed in the absence of oxygen. 1c is, however, photo-inactive and cannot be reversed back to 1a with UV or visible light irradiation. It was also found that 1c shows fluorescence whereas both 1a and 1b show no fluorescence.
Co-reporter:Huan-Huan Liu
Journal of Physical Organic Chemistry 2012 Volume 25( Issue 2) pp:142-146
Publication Date(Web):
DOI:10.1002/poc.1885
Photochromic diarylethenes bearing an intramolecular hydrogen bond in bridge moiety have been prepared. It is found that intramolecular hydrogen bonding has a great effect on both absorption and fluorescence of diarylethenes. The color change of diarylethenes in a wide range (purple, blue and green) can be achieved by simple modification of the electronic properties of substituents in bridge moiety, and fluorescent diarylethenes are also obtained when diarylethenes bear an intramolecular hydrogen bond in bridge moiety. Copyright © 2011 John Wiley & Sons, Ltd.
Co-reporter:Huan-huan Liu, Xu Zhang, Zeng Gao, and Yi Chen
The Journal of Physical Chemistry A 2012 Volume 116(Issue 40) pp:9900-9903
Publication Date(Web):September 18, 2012
DOI:10.1021/jp3070163
A photochromic diarylethene with N,N-dimethyl substituted group 1a was prepared. 1a showed ring-opening and ring-closing photoisomerization with UV/vis light irradiation. Treatment of 1a with CF3COOH produced a protonated diarylethene 1aH. With UV light irradiation, 1aH photoconverted to protonated ring-closed isomer 1c, which is photoinactive. It is found that 1c is hydrophilic and 1aH is hydrophobic.
Co-reporter:Shulie Han and Yi Chen
Journal of Materials Chemistry A 2011 vol. 21(Issue 33) pp:12402-12406
Publication Date(Web):18 Jul 2011
DOI:10.1039/C1JM11267H
We present the rapid fading of photochromic 3H-naphtho[2,1-b]pyrans at ambient temperature by protonation of N,N-disubstituted group. It is found that photochromic 3H-naphtho[2,1-b]pyrans with a N,N-disubstituted group are converted to protonated 3H-naphtho[2,1-b]pyran by treatment with acid, and the protonated 3H-naphtho[2,1-b]pyrans show rapid fading in both solution and a rigid polymer matrix at ambient temperature. It is also found that the protonated 3H-naphtho[2,1-b]pyrans exhibit similar absorption and fatigue resistance compared to their original compounds.
Co-reporter:Huan-huan Liu and Yi Chen
Journal of Materials Chemistry A 2011 vol. 21(Issue 4) pp:1246-1249
Publication Date(Web):09 Dec 2010
DOI:10.1039/C0JM02691C
A photochromic diarylethene (1a) with three bis(thien-3-yl) systems, containing a 2,5-dihydrothiophene unit and two imidazole units, has been prepared. 1a shows selective photochromism: upon irradiation with 365 nm, one bis(thien-3-yl) system containing a 2,5-dihydrothiophene unit is selected to undergo photocyclization reaction to form ring-closed isomer 1b, the other two bis(thien-3-yl) systems containing imidazole units are photo-inactive. With 254 nm light irradiation, all three bis(thien-3-yl) systems undergo photocyclization reaction to produce ring-closed isomer 1c. Selective solvatochromism was also observed at a ring-closed state: only 1c showed solvatochromism, and the solvatochromism was dependent on the solvent donor numbers: with the increase of donor numbers of solvent, the absorption of 1c shifted to shorter wavelength.
Co-reporter:Shulie Han and Yi Chen
Journal of Materials Chemistry A 2011 vol. 21(Issue 13) pp:4961-4965
Publication Date(Web):17 Feb 2011
DOI:10.1039/C1JM10139K
We have demonstrated that 3-aryl-3-(α-naphthalene)-3H-naphtho[2,1-b]pyrans photochromic system shows large optical density at photosteady state at ambient temperature. In this paper, we describe a strategy for modifying this photochromic system with a fast fading speed in both solution and in a rigid polymer matrix. It is found that the nature and position of the substituted groups attached to the aryl moiety at the 3-position play a key role in determining the fading speed of 3-aryl-3-(α-naphthalene)-3H-naphtho[2,1-b]pyrans at ambient temperature. The fading speed of colored forms increase significantly when the electron-donating groups are attached to the para-position of aryl moieties at the 3-position. Further investigations find that (1) a strong electron-donating group is better than a weak electron-donating group for a fast fading speed, (2) an electron-donating group attached to the para-position of the naphthalene ring is better than one attached to the para-position of a benzene ring, and (3) with electron-donating groups at both para-positions of the naphthalene and benzene rings, the fading speed is dramatically increased in both solution and in the rigid polymer matrix.
Co-reporter:Shulei Han, Yi Chen
Dyes and Pigments 2011 Volume 88(Issue 3) pp:235-239
Publication Date(Web):March 2011
DOI:10.1016/j.dyepig.2010.06.011
The conversion of 7-hydroxy-BIPS in solution from colourless form to colored form can be induced using both light and the addition of Hg2+ ion. No significant color change is observed when other ions (Ca2+, Mg2+, Zn2+, Cd2+, Co2+, Cu2+, Mn2+, Fe2+, Ni2+, Pb2+, K+, Na+, Li+, and Ag+) were used.
Co-reporter:Huan-Huan Liu, Yi Chen
Dyes and Pigments 2011 Volume 89(Issue 3) pp:212-216
Publication Date(Web):June 2011
DOI:10.1016/j.dyepig.2010.03.001
A new photochromic diarylethene 2a is synthesized and undergoes excellent ring-opening and ring-closing photoisomerization with UV/Vis light irradiation. The absorption of ring-closing isomer 2b (λmax = 615 nm, in dichloromethane) is found to match well with the fluorescence emission of dye 1 (λem = 610, ϕf = 0.76, in dichloromethane). By mixture of 1 and 2a in the ratio of 1:2.5 equiv., a simple and efficient fluorescence switching system is built. The fluorescence intensity of 1 is modulated easily with the photoisomerization of diarylethene 2a/2b by controlling irradiation time. With detecting fluorescence change, a readout method for multi-level optical storage is demonstrated.
Co-reporter:Xu Zhang
European Journal of Organic Chemistry 2011 Volume 2011( Issue 7) pp:1346-1350
Publication Date(Web):
DOI:10.1002/ejoc.201001500
Abstract
A phototriggered Cd2+ release complex has been prepared by using benzothiazoline as a ligand. With visible-light (λ ≥ 400 nm) irradiation, bound Cd2+ can be released from the complex, and the ligand is converted into a benzothiazole derivative. Accompanying the process of photoconversion, turn-on fluorescence is observed. The fluorescence intensity increases with photoconversion until Cd2+ is completely released, which provides a convenient method to monitor the phototriggered Cd2+ release process.
Co-reporter:Huan-Huan Liu
Journal of Physical Organic Chemistry 2011 Volume 24( Issue 6) pp:517-521
Publication Date(Web):
DOI:10.1002/poc.1798
Abstract
Modulation of color change and photocyclization of diarylethene with metal complex is described. A diarylethene derivative with 4-(ethylideneamino) phenol group 1a is prepared and photochromic behavior is investigated. It is found that 1a exhibits ring-opening and ring-closing photoisomerization with UV/Vis light irradiation in solution. Addition of Cu(OAc)2 to the solution of 1a produces a metal complex 1a–Cu, which generates not only marked color change but also significant promotion in photocyclization. Copyright © 2010 John Wiley & Sons, Ltd.
Co-reporter:Shulei Han and Yi Chen
Analytical Methods 2011 vol. 3(Issue 3) pp:557-559
Publication Date(Web):21 Jan 2011
DOI:10.1039/C0AY00633E
A reagent for colorimetric detection of Hg2+ in both solution and PMMA thin film has been investigated. It is found that 7-hydroxy-spiro-(2H-1-benzopyran-2,2′-indoline) shows highly selective colorimetric probing for Hg2+ in both solution and PMMA thin film. Addition of Hg2+ to the solution of reagent or dipping the reagent thin film into the solution of Hg2+ produces a distinct color change from colorless to red. Control experiments show that the colorimetric detection of Hg2+ is not affected by other competitive metal ions.
Co-reporter:Kunpeng Guo and Yi Chen
Journal of Materials Chemistry A 2010 vol. 20(Issue 20) pp:4193-4197
Publication Date(Web):08 Apr 2010
DOI:10.1039/C000610F
A photochromic naphthopyran system in which both optical density and fading speed of colored forms are significantly increased has been described. 3-Aryl-3-(α-naphthalene)-3H-naphtho[2,1-b]pyrans showed thermal stability, and a large optical density of colored forms was obtained at ambient temperature. By attachment of an alkoxyl group to the α-naphthalene group, the fading speed of colored forms was dramatically increased, and the fading speed was increased with increase of the length of alkoxyl chain. The generic nature of the system is beneficial for both the design of naphthopyran molecules with large optical density and fast fading speed at ambient temperature and applications.
Co-reporter:Xu Zhang and Yi Chen
Physical Chemistry Chemical Physics 2010 vol. 12(Issue 5) pp:1177-1181
Publication Date(Web):23 Dec 2009
DOI:10.1039/B917948H
A phototriggered Zn-release system with dual binding-sites and turn-on fluorescence has been developed by employing a molecule with two Schiff base units as a ligand. It is found that the ligand with two Schiff base units can bind with two Zn2+, and the bound Zn2+ can be released completely when the Schiff base is converted into bi-benzoxazole when phototriggered. During the conversion of the Schiff base into benzoxazole, the turn-on fluorescence was detected, which provides a convenient method to monitor the process of phototrigger release. Besides, it is also found that the amount of released Zn2+ depends on the exposure or irradiation time, which enables the possibility to manipulate the amount of Zn2+-release via controlling irradiation time.
Co-reporter:Kunpeng Guo and Yi Chen
Analytical Methods 2010 vol. 2(Issue 8) pp:1156-1159
Publication Date(Web):24 Jun 2010
DOI:10.1039/C0AY00316F
Aromatic primary amines with electron donors can be detected in the nanomolar range using cinnamaldehyde as reagent on thin layer chromatography plates (TLC plates). It was found that a yellow color spot appeared immediately when a colorless solution of amines mixed with a colorless solution of cinnamaldehyde on a TLC plate. Control experiments showed that no color change was detected when a substituted group of aromatic primary amines is changed from electron donor to electron acceptor. It also showed negative results when aromatic primary amines were replaced by aromatic secondary or tertiary amines as well as aliphatic amines. Sensitivity tests showed that the detectable limits for amines could be optimized, and the lower detectable limits of amines on TLC plate with cinnamaldehyde reagent are between 0.02 and 0.28 μg.
Co-reporter:Kunpeng Guo
Journal of Physical Organic Chemistry 2010 Volume 23( Issue 3) pp:207-210
Publication Date(Web):
DOI:10.1002/poc.1598
Abstract
A ‘locking and unlocking control’ for a photochromic molecular system has been developed by using a photochromic naphthopyran derivative 1a as the model compound. With UV light irradiation, the colorless solution of 1a underwent ring-opening photoisomerization and converted to a purple solution 1b, which quickly faded back to a colorless solution with visible light (λ ≥ 480 nm) irradiation or in the dark. Addition of boron trifluoride diethyl etherate to the solution of 1b produced a complex compound 2b, accompanying the color change from purple to blue. It was found that 2b remained photochemically inactive. With the addition of diethanolamine, however, the ‘locked’ photoreaction of 2b could be unlocked and converted back to 1b, in which the photochromism was recovered. Copyright © 2009 John Wiley & Sons, Ltd.
Co-reporter:Huan-Huan Liu, Yi Chen
Journal of Photochemistry and Photobiology A: Chemistry 2010 Volume 215(Issue 1) pp:103-107
Publication Date(Web):5 September 2010
DOI:10.1016/j.jphotochem.2010.08.002
A photochromic diarylethene derivative with 4-(ethylideneamino) phenol group (1a) is prepared, and 1a exhibits ring-opening and ring-closing photoisomerization with UV/vis light irradiation in solution. Addition of base to both solution of ring-open isomer 1a and ring-closed isomer 1b produces deprotonated compounds 2a and 2b, respectively, and both 2a and 2b are photo-inactive and no photochemical reaction is detected in solution in the absence of carbon dioxide and water. Both 2a and 2b are, however, converted back to 1a and 1b when the solution contains carbon dioxide and water, and photochromic reaction is recovered. This may provide a means to generate a gate for non-destructive readout. Meanwhile, the conversion between species is accompanied color change in a wide range by combination of photo-trigger and chemical trigger. The system endowed with multi-responsive functionality for multi-color change is beneficial for applications such as display and camouflage.
Co-reporter:Huanhuan Liu;Baoli Yao
Frontiers of Chemistry in China 2010 Volume 5( Issue 2) pp:221-225
Publication Date(Web):2010 June
DOI:10.1007/s11458-010-0112-x
A new photochromic diarylethene (1a) has been prepared. Both its photochromic behavior and nonlinear optical properties are investigated. 1a shows excellent ring-opening (λmax = 386 nm) and ring-closing (λmax = 652 nm) photoisomerization with UV-Vis light irradiation. With 800 nm femtosecond pulsed laser irradiation, 1a shows two-photon-induced photoisomerization, and a two-photon absorption cross-section (σ = 423×1050 cm4·s per photon) is obtained by using two-photon induced fluorescence method. The applications of two-photon absorption of 1a to holographic recording has been also investigated. A two-photon induced micro-pattern is recorded on the diarylethene 1a-PMMA film with an femtosecond laser of 800 nm, 100 fs, 1 kHz, 50 mW.
Co-reporter:Huan-Huan Liu and Yi Chen
Journal of Materials Chemistry A 2009 vol. 19(Issue 6) pp:706-709
Publication Date(Web):15 Dec 2008
DOI:10.1039/B812843J
A multi-addressable switching system has been constructed by employing photochromic diarylethene 1a, which is obtained by coupling photochromic 3,4-bis(5-formyl-2-methylthien-3-yl)-2,5-dihydrothiophene with 8-hydroxy-2-methylquinoline, as model compound. It is found that 1a exhibits ring-opening and ring-closing photoisomerization with UV/Vis light irradiation. Addition of trifluoroacetic acid to solution of 1a produces protonated diarylethene 2a, and 2a also performs photochromic behavior with distinguished color change. Both protonated ring-open isomer 2a and ring-closed isomer 2b reverse back to 1a and 1b by neutralization with base solution. Besides, a complex diarylethene 3a is formed when boron trifluoride diethyl etherate is added to a solution of 1a, and it is found that 3a also undergoes excellent photoisomerization.
Co-reporter:Kunpeng Guo and Yi Chen
Journal of Materials Chemistry A 2009 vol. 19(Issue 32) pp:5790-5793
Publication Date(Web):25 Jun 2009
DOI:10.1039/B905884B
A new kind of trigger for molecular switch has been developed using a photochromic spirooxazine derivative as a template system. It is found that the ring-opening and ring-closing interconversion of spirooxazine derivative can be performed by Lewis acid and base trigger instead of photoinducement. With Lewis acid trigger, the ring-closing species converts to ring-opening species via formation of a complex, and the complexed ring-opening species is thermal stable and photoinactive. Meanwhile, the complexed ring-opening species converts completely back to ring-closing species by decomplexation with Lewis base trigger, and the interconversion between ring-opening and ring-closing species can be cycled.
Co-reporter:Huan-huan Liu
European Journal of Organic Chemistry 2009 Volume 2009( Issue 30) pp:5261-5265
Publication Date(Web):
DOI:10.1002/ejoc.200900582
Abstract
A bifunctional metal detection system with independent signal outputs and regulable detection limits was developed by using a photochromic diarylethene with an imidazole unit as the ligand. The sensor can be used for the detection of Cu2+ by fluorescence recognition and for the detection of Na+ or K+ by colorimetric recognition. Moreover, the amount of component of the probe can be modulated and manipulated by photomodulation, which results in changes in the upper detectable limits; this enlarges the window of detectable limits for metal ions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Co-reporter:Xu Zhang Dr.
ChemPhysChem 2009 Volume 10( Issue 12) pp:1993-1995
Publication Date(Web):
DOI:10.1002/cphc.200900070
Co-reporter:Xu Zhang, Yi Chen
Analytica Chimica Acta 2009 650(2) pp: 254-257
Publication Date(Web):
DOI:10.1016/j.aca.2009.07.058
Co-reporter:Huan-huan Liu and Yi Chen
The Journal of Physical Chemistry A 2009 Volume 113(Issue 19) pp:5550-5553
Publication Date(Web):April 22, 2009
DOI:10.1021/jp810919j
A class of diarylethenes with a imidazole bridge unit has been synthesized and shows photochromic properties with UV/vis light irradiation. It is found that electronic properties of substituent in the imidazole bridge unit have a great effect on both photochromism and fluorescence of diarylethenes because of intramolecular charge transfer. Both “turn-on” and “turn-off” fluorescent diarylethenes systems can be achieved by simple modification of molecular structure and electronic properties of substituent, which provides a strategy for the design of new fluorescent diarylethene systems to be used as switches.
Co-reporter:Nan Xie and Yi Chen
Journal of Materials Chemistry A 2007 vol. 17(Issue 9) pp:861-865
Publication Date(Web):05 Dec 2006
DOI:10.1039/B613558G
Four novel fluorescent diarylethenes have been designed and synthesized. They showed excellent ring-opening and ring-closing photoisomerization properties with UV/Vis irradiation. It is found that both the ring-open and the ring-closed isomers have similar fluorescence emission, which is different from the known fluorescent diarylethenes for which the ring-open isomers exhibited strong fluorescence emission whereas the ring-closed isomers had no or weak fluorescence emission. It is also found that both the structural and the electronic properties of the substituent groups have a great influence on the absorption and emission of photochromic diarylethenes.
Co-reporter:Yizhe Dang
European Journal of Organic Chemistry 2007 Volume 2007(Issue 34) pp:5661-5664
Publication Date(Web):18 OCT 2007
DOI:10.1002/ejoc.200700779
A class of 3,4-diarylthiophenes was prepared in excellent yield (80–91 %) by oxidation of 3,4-diaryl-2,5-dihydrothiophenes with CuBr2. The approach is also available for the synthesis of 3,4-diarylpyrroles and 3,4-diarylfuran. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Co-reporter:Nan Xie, De X. Zeng, Yi Chen
Journal of Electroanalytical Chemistry 2007 Volume 609(Issue 1) pp:27-30
Publication Date(Web):15 October 2007
DOI:10.1016/j.jelechem.2007.06.009
3,4-Bis[5-(2′-thiophene)-2-methylthien-3-yl]-2,5-dihydrothiophene 1a was synthesized and underwent excellent ring-opening and ring-closing photoisomerization in solution with UV/Vis light irradiation. Both ring-open isomer and ring-closed isomer of diarylethene showed electrochemical behavior, and the oxidation/reduction potential was reversible based on the ring-opening and ring-closing photoisomerization of diarylethene with UV/Vis light irradiation. Besides, a combination of photochromism and electrochromism of 1a was also observed.
Co-reporter:Nan Xie, Yi Chen
Journal of Photochemistry and Photobiology A: Chemistry 2007 Volume 189(2–3) pp:253-257
Publication Date(Web):25 June 2007
DOI:10.1016/j.jphotochem.2007.02.008
A class of π-conjugated 1,4-bis(4,5-diarylimidazol)benzene dyes (1–5) are synthesized, and all dyes exhibit strong fluorescence in solution (ϕf = 0.96–0.45, in DMSO). It is found that both absorption and fluorescence of dyes are influenced by molecular structures and electronic properties of substitute groups, but little influenced by the polarity of solvents and pH value. Besides, two-photon properties of dyes are also investigated. The largest two-photon absorption cross-section (σ = 98 GM) for dye 4 is obtained with 700 nm in DMSO, and two-photon fluorescence emission is also observed with 740 nm excitation in solution.
Co-reporter:De X. Zeng, Yi Chen
Journal of Photochemistry and Photobiology A: Chemistry 2007 Volume 186(2–3) pp:121-124
Publication Date(Web):25 February 2007
DOI:10.1016/j.jphotochem.2006.07.019
A novel fluorescent probe, 5-(2-benzothzaole)-2-thiophene boronic acid (1), for Hg2+ detection in aqueous solution was synthesized. (1) exhibited very strong fluorescence emission (ϕ = 0.92) in tris–HCl (pH 7.42) buffer aqueous solution. It was found that the fluorescence emission of (1) was quenched significantly upon addition of Hg2+ in buffer aqueous solution, whereas no marked fluorescence quenching was detected with addition of other metal ions (Ba2+, Ca2+, Cd2+, Co2+, Cu2+, Mg2+, Fe2+, Fe3+, Ni2+, Pb2+, Zn2+, Na+, K+) expect for Fe2+ and Fe3+, for which a small fluorescence quenching was detected in same condition. Competition experiment showed that no obvious interference was observed in its fluorescence while (1) performed the titration with Hg2+ in the different mixtures of metal ions.
Co-reporter:Nan Xie, Yi Chen, Baoli Yao, Ming Lie
Materials Science and Engineering: B 2007 Volume 138(Issue 3) pp:210-213
Publication Date(Web):15 April 2007
DOI:10.1016/j.mseb.2007.01.013
A novel photochromic diarylethene with 2,5-dihydrothiophene bridging unit 1a was synthesized, and the photochromic properties of 1 were also investigated. It showed that 1 exhibited excellent ring-open and ring-closed photochromism with UV/vis light irradiation. Holographic recording was measured by employing the thin film of PMMA–diarylethene 1 as recording media. It showed that six different images were recorded in the same place on the sample with the dimension of 64 μm × 42 μm by the intersecting of the object beam and a reference beam with an intensity of 15 mW/cm2, and the stored information was readout by the attenuated reference beam with an intensity of 0.5 mW/cm2. In addition, preliminary investigations showed that the material was thermally stable and fatigue resistant.
Co-reporter:Nan Xie and Yi Chen
Journal of Materials Chemistry A 2006 vol. 16(Issue 10) pp:982-985
Publication Date(Web):09 Jan 2006
DOI:10.1039/B515347F
A novel photochromic diarylethene 1a with a fluorescent chromophore in the bridge moiety was synthesized. 1a showed fluorescent switching properties in solution with UV/VIS irradiation, accompanying the ring-opening and ring-closed photoisomerization of diarylethene 1a. Addition of acid to a solution of 1a produced protonated compound 2a, and 2a also showed fluorescent switching properties with UV/VIS irradiation.
Co-reporter:Nan Xie and Yi Chen
New Journal of Chemistry 2006 vol. 30(Issue 11) pp:1595-1598
Publication Date(Web):16 Aug 2006
DOI:10.1039/B609156C
A new photochromic diarylethene with oligothiophene side arm substituents has been synthesized. This diarylethene undergoes excellent photoisomerization with UV/Vis light irradiation, and shows fluorescence emission and electrochemical behavior. Both the fluorescence emission and oxidation/reduction potential are reversible based on the ring-opening and ring-closing photoisomerization of diarylethene with UV/Vis light irradiation, which may be used as a fluorescent and electrochemical switch. In addition, a combination of photochromism and electrochromism is observed for the diarylethene: the ring-closing reaction can be triggered by electrochemical oxidation while the ring-opening reaction must be photochemically driven.
Co-reporter:Nan Xie
Chinese Journal of Chemistry 2006 Volume 24(Issue 12) pp:
Publication Date(Web):4 DEC 2006
DOI:10.1002/cjoc.200690337
A hydroxyl substituted phenolic Schiff base 1, used as sensor for detection of Zn2+, was synthesized and investigated. It was found that a strong fluorescence emission was observed when 1 bound to Zn2+ in acetonitrile, whereas no fluorescence emission was detected when 1 bound to other metal ions (Fe2+, Co2+, Ni2+, Cu2+, Cd2+, Hg2+, Mg2+, Pb2+, Ca2+, Ba2+, Sr2+) except for Mg2+, for which a weak fluorescence emission was detected in the same condition. Competition experiment showed that no obvious interference was observed in its fluorescence while 1 performed the titration with Zn2+ in the different mixtures of metal ions. To understand the site where Zn2+coordinated to the ligand and the mechanism of binding, three other hydroxyl substituted phenolic Schiff bases 2–4 were synthesized and their binding reactions with Zn2+were also investigated.
Co-reporter:De-Xing Zeng
Chinese Journal of Chemistry 2006 Volume 24(Issue 2) pp:
Publication Date(Web):13 FEB 2006
DOI:10.1002/cjoc.200690050
3,4-Diaryl-2,5-dihydropyrrole with multiphotochromophore units 1a was synthesized and its photochromic properties were investigated. It showed that all photochromophore units underwent reversible ring-opening (1a) and ring-closing (1b) photoisomerization reactions in both solution and polymer film with UV/Vis light irradiation, and photochromic properties of 1a were similar to those of photochromic diarylethene with monophotochromophore 2a. It was found that the optical density of 1b was increased linearly with increase of the photochromophore units by comparison with that of 2b in the same condition. It was also found that no significant changes in absorption band and response time between diarylethenes with multiphotochromophores and monophotochromophore were detected in the same condition.
Co-reporter:Yi Chen, Jun P. Xiao, Baoli Yao, Mei G. Fan
Optical Materials 2006 Volume 28(8–9) pp:1068-1071
Publication Date(Web):June 2006
DOI:10.1016/j.optmat.2005.06.006
Two photochromic fulgides, 2-{2-[4-(N,N-dimethylnilino)-5-methyl-4-oxazoly]}ethylidene-4-(1-methylethylidene) tetrahydrofuran-2,5-dione (A) and 3-(1,2-dimethyl-5-phenyl-3-pyrolloethylidene)-4-(1-methylethylidene)tetrahydrofuran-2,5-dione (B), doped in PMMA as candidates of dual-wavelength optical memory for parallel recording has been investigated. With 488 nm-laser and 650 nm-laser, both “cross” and “star” images are recorded on the fulgides-PMMA film and read out clearly, respectively. Cross-talk between two fulgides in PMMA matrix and nondestructive readout has also been explored. The results show that no significant cross-talk is detected between them, and nondestructive readout is up to 201 times.
Co-reporter:Yi Chen, Nan Xie
Journal of Photochemistry and Photobiology A: Chemistry 2006 Volume 179(Issue 3) pp:320-323
Publication Date(Web):15 April 2006
DOI:10.1016/j.jphotochem.2005.08.036
A fluorescence spectroscopic system for detecting conversion of phenolic Schiff bases to benzoxazoles has been developed. It demonstrated that the conversion of benzoxazoles from phenolic Schiff bases in presence of NaOH with UV light irradiation can be monitored by fluorescence changes of benzoxazoles in solution. It also revealed that solvents have great effects on both the velocity of conversion reaction and conversion yield. This assay system may be used to rapid screen and optimize reaction conditions on small scale.
Co-reporter:Yi Chen and Nan Xie
Journal of Materials Chemistry A 2005 vol. 15(Issue 31) pp:3229-3232
Publication Date(Web):01 Jul 2005
DOI:10.1039/B506381G
A convenient system of modulation of a fluorescent switch based on photoisomerization of diarylethene has been demonstrated by employing 9,10-anthracenedinaphthalene 1 and benzothiazole diarylethene 2a as the fluorescence dye and the photochromic compound, respectively. The fluorescence change of 1 is modulated easily by photoisomerization of 2a, which is doped into the fluorescence dye, in solution as well as in a polymer film. The changes of fluorescence intensity of 1 between the “on” and “off” states are significant in both solution and polymer film and more than 20 cycles in solution and 10 cycles in polymer of fluorescence switching are achieved without distinguished change in fluorescence intensity.
Co-reporter:Yi Chen, Tiankai Li, Meigong Fan, Xuesong Mai, Hui Zhao, Duanyi Xu
Materials Science and Engineering: B 2005 Volume 123(Issue 1) pp:53-56
Publication Date(Web):15 November 2005
DOI:10.1016/j.mseb.2005.06.019
Photochromism of fulgide with dicyanomethylene a, doped in PMMA matrix, has been investigated. It showed that fulgide a undergoes photoisomerization reaction in PMMA film and exhibits fast response, high sensitivity as well as non-destructive readout. Besides, four-level recording of photochromic compound a used as recording media has also explored with 780 nm laser beam.
Co-reporter:Yi Chen, Congming Wang, Meigong Fan, Baoli Yao, Neimule Menke
Optical Materials 2004 Volume 26(Issue 1) pp:75-77
Publication Date(Web):June 2004
DOI:10.1016/j.optmat.2004.01.004
(N-4′-methoxy-2-methyl-5-phenyl)-3-pyrryl-ethylidene (isopropylidene) succinic anhydride fulgide, doped in PMMA matrix, exhibits photochromic behavior. The fatigue resistance experiment shows no photodegradation is detected after more than 450 writing–erasing cycles. Study of fulgide material for holographic recording media shows the optimal exposure and the diffraction efficiency is 1047 mJ/cm2 and 2.26%, respectively, with 10 μm thickness polymer film. Holographic grating with 1680 lines/mm at writing angle θ=30° is also obtained.
Co-reporter:Yi Chen ;De X. Zeng
ChemPhysChem 2004 Volume 5(Issue 4) pp:
Publication Date(Web):14 APR 2004
DOI:10.1002/cphc.200301021
Standing out from the crowd: The fluorescence intensity increases remarkably when a diarylethene ligand binds with Zn2+. By contrast, the fluorescence intensity is quenched when the ligand binds with other metal ions (see graphic) that compete with the zinc ion for binding sites.
Co-reporter:Huan-huan Liu and Yi Chen
Journal of Materials Chemistry A 2011 - vol. 21(Issue 4) pp:NaN1249-1249
Publication Date(Web):2010/12/09
DOI:10.1039/C0JM02691C
A photochromic diarylethene (1a) with three bis(thien-3-yl) systems, containing a 2,5-dihydrothiophene unit and two imidazole units, has been prepared. 1a shows selective photochromism: upon irradiation with 365 nm, one bis(thien-3-yl) system containing a 2,5-dihydrothiophene unit is selected to undergo photocyclization reaction to form ring-closed isomer 1b, the other two bis(thien-3-yl) systems containing imidazole units are photo-inactive. With 254 nm light irradiation, all three bis(thien-3-yl) systems undergo photocyclization reaction to produce ring-closed isomer 1c. Selective solvatochromism was also observed at a ring-closed state: only 1c showed solvatochromism, and the solvatochromism was dependent on the solvent donor numbers: with the increase of donor numbers of solvent, the absorption of 1c shifted to shorter wavelength.
Co-reporter:Nan Xie and Yi Chen
Journal of Materials Chemistry A 2007 - vol. 17(Issue 9) pp:NaN865-865
Publication Date(Web):2006/12/05
DOI:10.1039/B613558G
Four novel fluorescent diarylethenes have been designed and synthesized. They showed excellent ring-opening and ring-closing photoisomerization properties with UV/Vis irradiation. It is found that both the ring-open and the ring-closed isomers have similar fluorescence emission, which is different from the known fluorescent diarylethenes for which the ring-open isomers exhibited strong fluorescence emission whereas the ring-closed isomers had no or weak fluorescence emission. It is also found that both the structural and the electronic properties of the substituent groups have a great influence on the absorption and emission of photochromic diarylethenes.
Co-reporter:Huan-Huan Liu and Yi Chen
Journal of Materials Chemistry A 2009 - vol. 19(Issue 6) pp:NaN709-709
Publication Date(Web):2008/12/15
DOI:10.1039/B812843J
A multi-addressable switching system has been constructed by employing photochromic diarylethene 1a, which is obtained by coupling photochromic 3,4-bis(5-formyl-2-methylthien-3-yl)-2,5-dihydrothiophene with 8-hydroxy-2-methylquinoline, as model compound. It is found that 1a exhibits ring-opening and ring-closing photoisomerization with UV/Vis light irradiation. Addition of trifluoroacetic acid to solution of 1a produces protonated diarylethene 2a, and 2a also performs photochromic behavior with distinguished color change. Both protonated ring-open isomer 2a and ring-closed isomer 2b reverse back to 1a and 1b by neutralization with base solution. Besides, a complex diarylethene 3a is formed when boron trifluoride diethyl etherate is added to a solution of 1a, and it is found that 3a also undergoes excellent photoisomerization.
Co-reporter:Shulei Han and Yi Chen
Analytical Methods (2009-Present) 2011 - vol. 3(Issue 3) pp:NaN559-559
Publication Date(Web):2011/01/21
DOI:10.1039/C0AY00633E
A reagent for colorimetric detection of Hg2+ in both solution and PMMA thin film has been investigated. It is found that 7-hydroxy-spiro-(2H-1-benzopyran-2,2′-indoline) shows highly selective colorimetric probing for Hg2+ in both solution and PMMA thin film. Addition of Hg2+ to the solution of reagent or dipping the reagent thin film into the solution of Hg2+ produces a distinct color change from colorless to red. Control experiments show that the colorimetric detection of Hg2+ is not affected by other competitive metal ions.
Co-reporter:Kunpeng Guo and Yi Chen
Journal of Materials Chemistry A 2010 - vol. 20(Issue 20) pp:NaN4197-4197
Publication Date(Web):2010/04/08
DOI:10.1039/C000610F
A photochromic naphthopyran system in which both optical density and fading speed of colored forms are significantly increased has been described. 3-Aryl-3-(α-naphthalene)-3H-naphtho[2,1-b]pyrans showed thermal stability, and a large optical density of colored forms was obtained at ambient temperature. By attachment of an alkoxyl group to the α-naphthalene group, the fading speed of colored forms was dramatically increased, and the fading speed was increased with increase of the length of alkoxyl chain. The generic nature of the system is beneficial for both the design of naphthopyran molecules with large optical density and fast fading speed at ambient temperature and applications.
Co-reporter:Xu Zhang and Yi Chen
Physical Chemistry Chemical Physics 2010 - vol. 12(Issue 5) pp:NaN1181-1181
Publication Date(Web):2009/12/23
DOI:10.1039/B917948H
A phototriggered Zn-release system with dual binding-sites and turn-on fluorescence has been developed by employing a molecule with two Schiff base units as a ligand. It is found that the ligand with two Schiff base units can bind with two Zn2+, and the bound Zn2+ can be released completely when the Schiff base is converted into bi-benzoxazole when phototriggered. During the conversion of the Schiff base into benzoxazole, the turn-on fluorescence was detected, which provides a convenient method to monitor the process of phototrigger release. Besides, it is also found that the amount of released Zn2+ depends on the exposure or irradiation time, which enables the possibility to manipulate the amount of Zn2+-release via controlling irradiation time.
Co-reporter:Kunpeng Guo and Yi Chen
Journal of Materials Chemistry A 2009 - vol. 19(Issue 32) pp:NaN5793-5793
Publication Date(Web):2009/06/25
DOI:10.1039/B905884B
A new kind of trigger for molecular switch has been developed using a photochromic spirooxazine derivative as a template system. It is found that the ring-opening and ring-closing interconversion of spirooxazine derivative can be performed by Lewis acid and base trigger instead of photoinducement. With Lewis acid trigger, the ring-closing species converts to ring-opening species via formation of a complex, and the complexed ring-opening species is thermal stable and photoinactive. Meanwhile, the complexed ring-opening species converts completely back to ring-closing species by decomplexation with Lewis base trigger, and the interconversion between ring-opening and ring-closing species can be cycled.
Co-reporter:Kunpeng Guo and Yi Chen
Analytical Methods (2009-Present) 2010 - vol. 2(Issue 8) pp:NaN1159-1159
Publication Date(Web):2010/06/24
DOI:10.1039/C0AY00316F
Aromatic primary amines with electron donors can be detected in the nanomolar range using cinnamaldehyde as reagent on thin layer chromatography plates (TLC plates). It was found that a yellow color spot appeared immediately when a colorless solution of amines mixed with a colorless solution of cinnamaldehyde on a TLC plate. Control experiments showed that no color change was detected when a substituted group of aromatic primary amines is changed from electron donor to electron acceptor. It also showed negative results when aromatic primary amines were replaced by aromatic secondary or tertiary amines as well as aliphatic amines. Sensitivity tests showed that the detectable limits for amines could be optimized, and the lower detectable limits of amines on TLC plate with cinnamaldehyde reagent are between 0.02 and 0.28 μg.
Co-reporter:Shulie Han and Yi Chen
Journal of Materials Chemistry A 2011 - vol. 21(Issue 13) pp:NaN4965-4965
Publication Date(Web):2011/02/17
DOI:10.1039/C1JM10139K
We have demonstrated that 3-aryl-3-(α-naphthalene)-3H-naphtho[2,1-b]pyrans photochromic system shows large optical density at photosteady state at ambient temperature. In this paper, we describe a strategy for modifying this photochromic system with a fast fading speed in both solution and in a rigid polymer matrix. It is found that the nature and position of the substituted groups attached to the aryl moiety at the 3-position play a key role in determining the fading speed of 3-aryl-3-(α-naphthalene)-3H-naphtho[2,1-b]pyrans at ambient temperature. The fading speed of colored forms increase significantly when the electron-donating groups are attached to the para-position of aryl moieties at the 3-position. Further investigations find that (1) a strong electron-donating group is better than a weak electron-donating group for a fast fading speed, (2) an electron-donating group attached to the para-position of the naphthalene ring is better than one attached to the para-position of a benzene ring, and (3) with electron-donating groups at both para-positions of the naphthalene and benzene rings, the fading speed is dramatically increased in both solution and in the rigid polymer matrix.
Co-reporter:Xu Zhang and Yi Chen
Physical Chemistry Chemical Physics 2012 - vol. 14(Issue 7) pp:NaN2316-2316
Publication Date(Web):2012/01/11
DOI:10.1039/C2CP23265K
Photo-controlled metal-ion (Zn2+ and Cd2+) release in aqueous micelle solution (tris-HCl, pH = 7.4) has been described using 2-((2-mercaptophenylimino)methyl) phenol as ligand. It is found that both the ligand-Zn complex (1) and the ligand-Cd complex (2) are stable in micelle solution, and Zn2+ (Cd2+) can be released from the complex with 365 nm light trigger. Accompanying the metal-ion release, the ligand is photo-converted to 2-(benzothiazol-2-yl) phenol (3) as product, and the turn-on fluorescence is detected. The fluorescence intensity increases with the photo-triggered release until Zn2+ (Cd2+) is completely released, which is beneficial for monitoring the process of photo-controlled metal ion release. Control experiments demonstrate that no binding occurs between 3 and Zn2+ (Cd2+) in micelle solution and there is no binding between cations and micelle, either.
Co-reporter:Shulie Han and Yi Chen
Journal of Materials Chemistry A 2011 - vol. 21(Issue 33) pp:NaN12406-12406
Publication Date(Web):2011/07/18
DOI:10.1039/C1JM11267H
We present the rapid fading of photochromic 3H-naphtho[2,1-b]pyrans at ambient temperature by protonation of N,N-disubstituted group. It is found that photochromic 3H-naphtho[2,1-b]pyrans with a N,N-disubstituted group are converted to protonated 3H-naphtho[2,1-b]pyran by treatment with acid, and the protonated 3H-naphtho[2,1-b]pyrans show rapid fading in both solution and a rigid polymer matrix at ambient temperature. It is also found that the protonated 3H-naphtho[2,1-b]pyrans exhibit similar absorption and fatigue resistance compared to their original compounds.
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