- Synthesis and the optoelectronic properties of diarylethene derivatives having benzothiophene and n-alkyl thiophene units
-
Six new unsymmetrical diarylethenes having both benzothiophene and n-alkylthiophene units have been synthesized. The structures of diarylethenes 2a-6a were determined by single-crystal X-ray diffraction analysis. The results showed that the alkyl chain le
- Pu, Shouzhi,Li, Min,Fan, Congbin,Liu, Gang,Shen, Liang
-
-
Read Online
- Photoswitchable "turn-on" Fluorescence Diarylethenes: Substituent Effects on Photochemical Properties and Electrochromism
-
A series of "turn-on" fluorescence diarylethenes derived from 2,3-bis(2-methylbenzo[b]thiophen-3-yl)-5,6-dihydro-4H-thieno[2,3-b]thiopyran-4-one (1) with alkyl and acetyl substituents were synthesized. The photochemical and photophysical properties of these derivatives, including the photoreaction of crystalline 1, were thoroughly investigated to reveal substituent effects on their properties. The results indicated that alkyl substituents did not significantly affect the absorption and emission spectra of the diarylethenes. However, large absorption and emission wavelength shifts were observed for the diarylethene with an acetyl substituent due to extension of π-π conjugation. Significantly, all of the fluorescent ring-closed forms of the compounds isomerized to their ring-open forms in the presence of Cu2+ in the dark. EPR results provide clear evidence for the formation of the compound 1 radical cation intermediate that might be generated in the reaction between c-1 and Cu2+. DFT calculations found that the ground-state activation energy for ring-opening of 1.+ was approximately 9.2 kcal mol-1 lower than that of 1 without Cu2+, such that a Cu2+-catalyzed oxidative cycloreversion reaction at room temperature might be possible.
- Ai, Qi,Pang, Shichong,Ahn, Kwang-Hyun
-
-
Read Online
- Fully Reversible Multistate Fluorescence Switching: Organogel System Consisting of Luminescent Cyanostilbene and Turn-On Diarylethene
-
Multicolor tunable and multistate switchable organogel is reported, which consists of a cyanostilbene organogelator showing aggregation-induced enhanced emission and a turn-on type photochromic diarylethene dye. The mixed organogel can be reversibly switched among four different states (blue-emitting gel, nonemissive sol, green-emitting gel, and green-emitting sol) modulated by a combination of orthogonal stimuli of heat and light. It is interestingly noted that this four-state switching constitutes a combinational logic circuit consisting of two stimuli inputs and three outputs. Reversible fluorescence writing, switching, erasing, and image patterning processes on this mixture gel system are demonstrated.
- Kim, Dojin,Kwon, Ji Eon,Park, Soo Young
-
-
Read Online
- Syntheses and substituent effects on the properties of unsymmetrical photochromic diarylethenes bearing a benzothiophene unit
-
Photochromic unsymmetrical diarylethenes 1a5a that bear different electron-donating or electron-withdrawing substitutes have been synthesized, and the structures of 2a5a determined by single-crystal X-ray diffraction analysis. Substituent effects on their
- Pu, Shouzhi,Li, Min,Liu, Gang,Le, Zhanggao
-
-
Read Online
- Regulation of an Ambient-Light-Induced Photocyclization Pathway (Norrish–Yang Versus 6π) by Substituent Choice
-
Photocyclization, irrespective of whether multiple steps (e.g., Norrish–Yang cyclization) or a single concerted step (e.g., 6π photocyclization) are involved, is an intramolecular photochemical process resulting in the formation of one new single bond to afford a ring system. In particular, visible-light-induced photocyclization offers a green and sustainable route to organic cyclic compounds that are difficult to access by thermal reactions. Herein, we describe the ambient light-induced intramolecular photocyclization of a series of donor/acceptor chromophores 1 d–3 d containing two types of photoresponsive motifs, namely an electron-deficient BF2-chelated ketone fused with an electron-rich thiophene, and probe the solution-phase and solid-state photochromic performance of these compounds. The results reveal that simple variation of R substituents on the diaryl moiety allows one to control the intramolecular photocyclization mechanism with high photochemical selectivity, e.g., under ambient light, methyl-substituted 1 d and 2 d undergo reversible 6π photocyclization, whereas ethyl-substituted 3 d exclusively undergoes irreversible Norrish–Yang photocyclization. Single-crystal X-ray analysis of Norrish–Yang cyclization products reveals the formation of four pairs of conformational enantiomers differing in the dihedral angle between benzothiophene and the BF2 core, namely (±)N-3 d@68°, (±)N-3 d@-77°, (±)N-3 d@-78°, and (±)N-3 d@-102°. The UV/Vis absorption spectra of 1 d–3 d cover a broad visible-light region (380–572 nm), while DFT and TD-DFT calculations reveal that absorption in this region is dominated by the charge-transfer (CT) transition from the thiophene-centered HOMO to the LUMO of the electron-deficient π-conjugated BF2-chelated unit and the n→π* and π→π* transitions within the latter unit. The spatial separation of the HOMO and LUMO of these dyes promotes triplet-state generation and self-photosensitizes intramolecular photocyclization in the visible-light region. Three-dimensional time-resolved and steady-state emission spectra of 3 d show that the Norrish–Yang photocyclization takes place within milliseconds with excellent conversion efficiency (96 %).
- Liu, Hui,Gao, Hu,Wang, Sisi,Yao, Shengxin,Wu, Fan,Zhao, Yue,Chan, Kin Shing,Shen, Zhen
-
-
Read Online
- Mono-and bithiophene-substituted diarylethene photoswitches with emissive open or closed forms
-
We present a new series of photochromic 1,2-bis(2-ethylbenzo[b]thiophen-3-yl)perfluorocyclopentenes with an oxidized benzothiophene core (O) or a nonoxidized one, decorated with mono-(Th1) and bithiophene (Th2) units attached to positions 6 and 6′ (Sy = symmetric) or only to position 6 (As = asymmetric). Oxidized compounds have highly fluorescent closed forms emitting in the visible region (yellow to red). The dyes with nonoxidized benzothiophenes possess fluorescent open forms with rather low emission efficiency. The photoswitching kinetics was studied at several wavelengths with UV and visible light. New diarylethenes underwent ring-closure reactions by irradiation with UV light (365 nm, 405 nm), and the reversible ring-opening by irradiation with visible light (470 nm, 530 nm). The on-switching of fluorescence due to the ring-closure reaction was observed also with visible light of 470 nm (to an extent of 10% for compound SyOTh1) and attributed to the Urbach tail effect. Due to a high degree of fluorescence modulation (>270), good fatigue resistance and large fluorescence quantum yield, compound SyOTh1 emerged as a candidate for single-molecule based super-resolution fluorescence microscopy.
- Schleper, A. Lennart,Bossi, Mariano L.,Belov, Vladimir N.,Hell, Stefan W.
-
-
Read Online
- Photochromic diaryl ethylene compound with up-conversion luminescence property and application thereof
-
The invention provides a photochromic diaryl ethylene compound with up-conversion luminescence performance and application thereof. The photochromic diaryl ethylene compound has a structure as shown in a formula I in the specification. The photochromic diaryl ethylene compound is a switching type single-photon absorption up-conversion luminescent material, can realize up-conversion luminescence of high-vibration energy level absorption, and can realize the switching effect of up-conversion luminescence through regulation and control of light with multiple wavelengths. Due to the fact that light with a long wavelength has a high tissue penetrating power, the photochromic diaryl ethylene compound can also effectively eliminate background noise such as auto-fluorescence, and is expected to be applied to a super-resolution single-photon imaging system.
- -
-
Paragraph 0101-0107
(2021/05/26)
-
- Fluorescence opening type diarylethene fluorescent probe, and preparation method and application thereof
-
The invention provides a fluorescence opening type diarylethene fluorescent probe, and a preparation method and application thereof. The fluorescence opening type diarylethene fluorescent probe has a structure as shown in a formula I, the probe is compose
- -
-
Paragraph 0075-0079
(2021/07/28)
-
- Development of Red-Shifted and Fluorogenic Nucleoside and Oligonucleotide Diarylethene Photoswitches
-
The reversible modulation of fluorescence signals by light is of high interest for applications in super-resolution microscopy, especially on the DNA level. In this article we describe the systematic variation of the core structure in nucleoside-based diarylethenes (DAEs), in order to generate intrinsically fluorescent photochromes. The introduction of aromatic bridging units resulted in a bathochromic shift of the visible absorption maximum of the closed-ring form, but caused reduced thermal stability and switching efficiency. The replacement of the thiophene aryl unit by thiazol improved the thermal stability, whereas the introduction of a benzothiophene unit led to inherent and modulatable turn-off fluorescence. This feature was further optimized by introducing a fluorescent indole nucleobase into the DAE core, resulting in an effective photoswitch with a fluorescence quantum yield of 0.0166 and a fluorescence turn-off factor of 3.2. The site-specific incorporation into an oligonucleotide resulted in fluorescence-switchable DNA with high cyclization quantum yields and switching efficiency, which may facilitate future applications.
- Kolmar, Theresa,Becker, Antonia,Pfretzschner, Ronja A.,Lelke, Alina,J?schke, Andres
-
supporting information
p. 17386 - 17394
(2021/10/20)
-
- Di(benzothienyl)cyclobutenes: Toward Strained Photoswitchable Fluorophores
-
Bis(benzothienyl)ethene sulfones are very interesting molecules for super-resolution microscopy due to their photoswitching properties. However, functionalization of the ‘classical’ bis(benzothienyl)ethene sulfones with a five-membered central ring leads to significant decrease of quantum yields of photoconversion of the fluorescent closed form of the dye to the non-fluorescent open form that limits their application in microscopy. Here, we designed and synthesized diarylethenes with a fluorinated four-membered central ring that adds extra strain to the closed form of the dye. The reaction mechanism of their formation was studied, and byproducts formed upon structural rearrangement of the benzothiophene fragment were characterized. The photochromic properties of the new molecules were investigated by NMR and absorption spectroscopy. Some of these compounds show enhanced tendency to ring opening and have quantum yields of the ring-opening reaction in the range of 0.2–0.5.
- Klepetá?ová, Blanka,Pohl, Radek,Procházková, Eli?ka,Semenenko, Aleksander,Shishkina, Svitlana,Shvadchak, Volodymyr,Sysoiev, Dmytro,Yushchenko, Dmytro A.
-
p. 2084 - 2092
(2020/10/06)
-
- Highly Efficient Enantioselective Synthesis of Chiral Sulfones by Rh-Catalyzed Asymmetric Hydrogenation
-
A highly efficient and enantioselective Rh-(R,R)-f-spiroPhos complex catalyzed hydrogenation of a series of unsaturated sulfones has been developed. With Rh-(R,R)-f-spiroPhos catalyst under mild conditions, not only the asymmetric hydrogenation of both the 3,3-diaryl and exocyclic α,β-unsaturated sulfones was first realized with up to 99.9% ee but also 3-alkyl-3-aryl and benzo[b]thiophene-1,1-dioxides were successfully hydrogenated to the corresponding chiral sulfones with excellent enantioselectivities (up to 99.4% ee) regardless of the steric hindrance, electronic property, and geometry of the substrates. Moreover, this reaction offers a route to (S)-(+)-ar-turmerone as a spice flavor, which is an important synthetic intermediate of pharmaceuticals.
- Yan, Qiaozhi,Xiao, Guiying,Wang, Ying,Zi, Guofu,Zhang, Zhanbin,Hou, Guohua
-
supporting information
p. 1749 - 1756
(2019/01/25)
-
- Construction of Highly Emissive Pt(II) Metallacycles upon Irradiation
-
Photoswitchable or photoactivatable fluorescent species have been found wide applications within supramolecular chemistry and materials science. In this study, we successfully constructed two highly emissive Pt(II) metallacycles from the diarylethene ligands via coordination-driven self-assembly. Different from the most known fluorescent metallacycles, the obtained metallacycles have displayed “turn-on” fluorescence switching. They are non-fluorescent in solution, but they emit highly yellow or orange fluorescence under ultraviolet irradiation. The metallacycles were well characterized by 1H NMR, 31P NMR and ESI-TOF-MS. The photochromic properties of the resultant metallacycles were investigated by 1H NMR, 31P NMR, UV/Vis spectrum and fluorescence spectrum. Notably, NMR studies revealed that these two metallacycles featured excellent cyclization efficiency (90% conversion efficiency). Moreover, the closed-ring isomers of the metallacycles displayed relatively high quantum yield (ΦF = 0.5). DFT simulations demonstrated that the antiparallel configuration of the diarylethene ligand had an angle closed to 120°, which was more stable in energy compared to the parallel configuration, thus allowing for the facile construction of highly emissive metallacycles. We believe that such highly emissive metallacycles which are in-situ prepared upon irradiation can be used as new fluorescence materials for sensing and bioimaging in the future.
- Qin, Yi,Zhang, Ying,Yin, Guangqiang,Wang, Yuxuan,Zhang, Changwei,Chen, Lijun,Tan, Hongwei,Li, Xiaopeng,Xu, Lin,Yang, Haibo
-
supporting information
p. 323 - 329
(2019/03/07)
-
- Iridium-Catalyzed Asymmetric Hydrogenation of Benzo[b]thiophene 1,1-Dioxides
-
An efficient iridium-catalyzed asymmetric hydrogenation of substituted benzothiophene 1,1-dioxides is described. The use of iridium complexes with chiral pyridyl phosphinite ligands provides access to highly enantiomerically enriched sulfones with substituents at the 2- and 3-position. Sulfones of this type are of interest as core structures of agrochemicals and pharmaceuticals. Moreover, they can be further reduced to chiral 2,3-dihydrobenzothiophenes.
- Tosatti, Paolo,Pfaltz, Andreas
-
supporting information
p. 4579 - 4582
(2017/04/11)
-
- Cyclopenta[b]annulation of Heteroarenes by Organocatalytic γ′[C(sp3)?H] Functionalization of Ynones
-
A new approach for the cyclopenta[b]annulation of heteroarenes through metal-free and directing-group-free γ′[C(sp3)?H] functionalization and intramolecular hydroalkylation of ynones has been developed. In an unprecedented event, nucleophilic addition of an organophosphine to the designed ynones triggers γ′[C(sp3)?H] functionalization, leading to the formation of heteroaryl-based ortho-quinodimethane (oQDM) intermediates that undergo carbocyclization to provide cyclopentannulated heteroarenes in good yields and excellent stereoselectivities. Deuterium-labeling experiments substantiated the proposed reaction mechanism as well as the speculated epimerization.
- Raghu, Moluguri,Grover, Jagdeep,Ramasastry
-
supporting information
p. 18316 - 18321
(2016/12/16)
-
- Experimental and theoretical investigation of tetra-oxidized terarylenes with high-contrast fluorescence switching
-
Tetra-oxidized terarylenes having ethyl groups at the reactive carbon atoms are synthesized and their photophysical properties are studied. Their closed-ring isomers exhibit much lower cycloreversion quantum yields and relatively high fluorescence quantum
- Kanazawa, Rui,Taguchi, Maki,Nakashima, Takuya,Kawai, Tsuyoshi
-
supporting information
p. 7397 - 7402
(2015/09/02)
-
- WATER-SOLUBLE PHOTOCHROMIC MOLECULE
-
A diarylethene compound having high water-solubility is provided, and the compound is a diarylethene compound of formula (I) wherein, Sg is a monovalent sugar-type residue consisting of a sugar-type compound (in which some of hydroxyl groups may be protected) selected from a group consisting of a six-membered ring sugar, a five-membered ring sugar, cyclitol and oligosaccharides containing a six-membered ring sugar, a five-membered ring sugar, or cyclitol and excluding an hydroxyl group; U is -(CH2)n-, -CH2-U'-, or -C(=O)- (wherein, n is an integer of 1 to 5, U' is a C1-C10 alkyl group binding to Ar); and Ar is a group represented by formula (A1) or (A2); wherein, X is S, SO2, NR3 (R3 is a C1-C3 alkyl group) or O, R is C1-C4 alkyl group, R1 and R2 are independently a C1-C3 alkyl group, a is 0 or 1, b is an integer of 0-3, and * represents a bond with U); Y is a hydrogen atom or a halogen atom; m is an integer of 5-7.
- -
-
Paragraph 0116; 0117
(2015/09/22)
-
- HETEROARYL COMPOUNDS AND METHODS OF USE THEREOF
-
Provided herein are thiophene compounds, methods of their synthesis, pharmaceutical compositions comprising the compounds, and methods of their use. The compounds provided herein are useful for the treatment, prevention, and/or management of various neurological disorders, including but not limited to, psychosis and schizophrenia.
- -
-
Paragraph 00289
(2013/08/28)
-
- Asymmetric hydrogenation of thiophenes and benzothiophenes
-
An efficient and highly asymmetric ruthenium-N-heterocyclic carbene-catalyzed hydrogenation of substituted thiophenes and benzothiophenes is described, providing a new strategy for the formation of valuable enantiomerically pure tetrahydrothiophenes and 2,3-dihydrobenzothiophenes.
- Urban, Slawomir,Beiring, Bernhard,Ortega, Nuria,Paul, Daniel,Glorius, Frank
-
supporting information
p. 15241 - 15244
(2012/11/07)
-
- N-aryl thienyl-, furyl-, and pyrrolyl-sulfonamides and derivatives thereof that modulate the activity of endothelin
-
Thienyl-, furyl- and pyrrolyl-sulfonamides and methods for modulating or altering the activity of the endothelin family of peptides are provided. In particular, N-(isoxazolyl)thienylsulfonamides, N-(isoxazolyl)furylsulfonamides and N-(isoxazolyl)pyrrolylsulfonamides and methods using these sulfonamides for inhibiting the binding of an endothelin peptide to an endothelin receptor by contacting the receptor with the sulfonamide are provided. Methods for treating endothelin-mediated disorders by administering effective amounts of one or more of these sulfonamides or prodrugs thereof that inhibit or increase the activity of endothelin are also provided.
- -
-
Page column 65
(2010/01/30)
-
- Biphenylsulfonamides and derivatives thereof that modulate the activity of endothelin
-
Biphenylsulfonamides and methods for modulating or altering the activity of the endothelin family of peptides are provided. In particular, bicyclic or tricyclic carbon or heterocyclic ring biphenylsulfonamides and methods using these sulfonamides for inhibiting the binding of an endothelin peptide to an endothelin receptor by contacting the receptor with the sulfonamide are provided. Methods for treating endothelin-mediated disorders by administering effective amounts of one or more of these sulfonamides or prodrugs thereof that inhibit or increase the activity of endothelin are also provided.
- -
-
-
- THIENYL-, FURYL- AND PYRROLYL SULFONAMIDES AND DERIVATIVES THEREOF THAT MODULATE THE ACTIVITY OF ENDOTHELIN
-
Thienyl-, furyl-and pyrrolyl-sulfonamides and methods for modulating or altering the activity of the endothelin family of peptides are provided. In particular, N-(isoxazolyl)thienylsulfonamides, N-(isoxazolyl) furylsulfonamides and N-(isoxazolyl)pyrrolylsulfonamides and methods using these sulfonamides for inhibiting the binding of an endothelin peptide to an endothelin receptor by contacting the receptor with the sulfonamide are provided. Methods for treating endothelin-mediated disorders by administering effective amounts of one or more of these sulfonamides or prodrugs thereof that inhibit or increase the activity of endothelin are also provided.
- -
-
-
- Flash Vacuum Pyrolysis of Stabilised Phosphorous Ylides. Part 3. Preparation of o-Methoxyphenyl- and o-Methylsulfanylphenyl-alkynes and their Cyclisation to Benzofuranes and Benzothiophenes
-
Fourteen new β-oxo phosphorus ylides 1 - 14 bearing o-methoxybenzoyl or o-(methylsulfanyl)benzoyl groups have been prepared and their pyrolytic behaviour studied.While flash vacuum pyrolysis (FVP) at 700 deg C brings about extrusion of Ph3PO to give the expected alkynes 16, this is accompained at 850 deg C by loss of Me* and cyclisation of the resulting radicals to afford 2-substituted benzofurans or benzothiophenes 17 - 24.Where the substituent R1 on the ylidic carbon of the starting material is phenyl, this is incorporated unchanged into the heterocyclic products.Where R1 is Et or Pri the vinyl products are formed by intramolecular abstraction of a β-hydrogen atom following cyclisation.For R1 = Me, Pr, Bu, and C5H11 the cyclisation is followed by hydrogen atom abstraction from the alkyl group leading to its fragmentation and giving products with 2-methyl, ethyl and vinyl substituents.In these cases the products can be accounted for by a radical chain reaction involving the unusual homolytic substitution of a carbon radical at a saturated carbon atom.
- Aitken, R. Alan,Burns, Graham
-
p. 2455 - 2460
(2007/10/02)
-
- A NEW SYNTHESIS OF 2-SUBSTITUTED BENZOFURANS AND BENZOTHIOPHENS: NOVEL FRAGMENTATION REACTIONS OF SIMPLE ALKYL GROUPS
-
Flash vacuum pyrolysis of (2-methoxy- and (2-methylthiobenzoyl)alkylidenetriphenylphosphoranes results in loss of Ph3PO and methyl radical; cyclisation of the resulting radical intermediates leads to benzofurans and benzothiophens in which the 2-substituents have undergone novel fragmentation processes.
- Aitken, R. Alan,Burns, Graham
-
p. 3717 - 3718
(2007/10/02)
-
- Photochemical Cycloadditions of 2,3-Dihalobenzothiophenes: Stereochemical and Mechanistic Results
-
Synthetic approaches to 2-thia-3,4-benzobicyclo-1,3,6-heptatriene and to 2-thia-3,4-benzobicyclo-1,3-heptadiene requiered halogenated cyclobutanes derived from ?2s + ?2s> photocycloadditions of 2,
- Neckers, D. C.,Wagenaar, F. L.,Hauenstein, D.,Jacobson, R. A.
-
p. 1725 - 1732
(2007/10/02)
-