- Visible Light Stimulated Bistable Photo-Switching in Defect Engineered Metal-Organic Frameworks
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The incorporation of photoactive donor-acceptor Stenhouse adduct (DASA) moieties into Metal-Organic Frameworks (MOFs) provides a new route to the development of visible light switching materials. Herein, a DUT-5 mixed-linker defect series was exploited to produce a derivative group of DASA-modified materials via postsynthetic modification (PSM). The photoactive MOFs exhibited conversion stimulated by visible wavelengths and were stable following multiple cycles. Thermodynamic and metastable states persisted over an extended time period.
- Shepherd, Nicholas D.,Wang, Tiesheng,Ding, Bowen,Beves, Jonathon E.,D'Alessandro, Deanna M.
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Read Online
- A novel multiphotochromic system with orthogonal light excitations
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Multiphotochromic systems are of immense importance for promising applications nowadays, while it remains a formidable challenge to develop a compound containing various photoswitches with spectral complementarity. Herein, we describe a novel multiphotoch
- Li, Mingming,Yang, Shun,Liang, Wenjing,Zhang, Xiukang,Qu, Dahui
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Read Online
- π-Bridge Substitution in DASAs: The Subtle Equilibrium between Photochemical Improvements and Thermal Control**
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Donor–acceptor Stenhouse adducts (DASAs) are playing an outstanding role as innovative and versatile photoswitches. Until now, all the efforts have been spent on modifying the donor and acceptor moieties to modulate the absorption energy and improve the c
- Martínez-López, David,Santamaría-Aranda, Eduardo,Marazzi, Marco,García-Iriepa, Cristina,Sampedro, Diego
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supporting information
p. 4420 - 4429
(2021/02/01)
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- Promoting the Furan Ring-Opening Reaction to Access New Donor–Acceptor Stenhouse Adducts with Hexafluoroisopropanol
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Donor–acceptor Stenhouse adducts (DASAs) are visible-light-responsive photoswitches with a variety of emerging applications in photoresponsive materials. Their two-step modular synthesis, centered on the nucleophilic ring opening of an activated furan, ma
- Clerc, Michèle,Stricker, Friedrich,Ulrich, Sebastian,Sroda, Miranda,Bruns, Nico,Boesel, Luciano F.,Read de Alaniz, Javier
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supporting information
p. 10219 - 10227
(2021/03/22)
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- Properties of a furan ring-opening reaction in aqueous micellar solutions for selective sensing of mesalazine
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A novel and efficient non-azo formation based method was developed for trace sensing of mesalazine (MES), a pharmaceutical aromatic amine. MES was simply coupled with a Meldrum's activated furan (MAF) reagent via a furan ring opening reaction to form a colored product. The intense purple colored solution was detected at 575 nm. The reaction of MES with MAF was monitored by employing 1H NMR spectroscopy and mass spectrometry. In addition, density functional theory (DFT) was applied to optimize the structure of the colored product and its λmax (the wavelength of maximum absorbance) in dimethyl sulfoxide and water. The colored product was considered in three possible structures, and the most possible structures in dimethyl sulfoxide and in water were identified by employing the DFT calculations. Both of the most possible structures indicated only a local excitation in their λmax and no charge transfer was observed. However, one of the structures in dimethyl sulfoxide presented charge transfer properties occurring through N–C[dbnd]C–C moiety. A univariate optimization method was also used to attain the optimum condition for analysis. In addition, the dependence of the analytical response on the three main affecting parameters (reaction time (X1), Triton X-100 concentration (X2) and MAF concentration (X3)) was identified by employing a central composite design (CCD) approach. The CCD study showed that the analytical response depends complexly on the parameters. Beer's law was obeyed within the range of 0.06–9.30 μg mL?1 of MES (155 fold linearity) at 575 nm, under the optimum condition introduced by the CCD approach. Also, the limit of detection was obtained 0.04 μg mL?1 of MES. The method showed precision (as relative standard deviation) and accuracy (as recovery) within the ranges of 0.6–3.2 % and 96.3–100.8%, respectively. Various organic and inorganic species, amino-pharmaceuticals, and amino acids were tested to evaluate the selectivity of the method. The selectivity of the analytical method was satisfactory. The method was successfully applied for detection of MES in various water matrices and pharmaceutical tablets.
- Sabahi-Agabager, Leila,Eskandari, Habibollah,Nasiri, Farough,Shamkhali, Amir Nasser,Baghi Sefidan, Somayyeh
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- New donor-acceptor stenhouse adducts as visible and near infrared light polymerization photoinitiators
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Polymerization photoinitiators that can be activated under low light intensity and in the visible range are being pursued by both the academic and industrial communities. To efficiently harvest light and initiate a polymerization process, dyes with high molar extinction coefficients in the visible range are ideal candidates. In this field, Donor-acceptor Stenhouse Adducts (DASA) which belong to a class of recently discovered organic photochromic molecules still lack practical applications. In this work, a series of DASA-based dyes are proposed as photoinitiators for the free radical polymerization of (meth)acrylates upon exposure to a near infrared light (laser diode at 785 nm).
- Bonardi, Aude-Héloise,Dumur, Frédéric,Duval, Sylvain,Gigmes, Didier,Lalevée, Jacques,Noirbent, Guillaume,Xu, Yangyang
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supporting information
(2020/05/28)
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- One-Pot Knoevenagel and [4 + 2] Cycloaddition as a Platform for Calliviminones
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Bioactive compounds featuring an unusual core of spiro[5.5]undecenes and calliviminones were synthesized in very good yield with good regio- and diastereoselectivities through a one-pot Knoevenagel and [4 + 2] cycloaddition from the readily available aldehydes, cyclic-1,3-diones, dienes, and a catalytic amount of (s)-proline.
- Roy, Pritam,Anjum, S. Rehana,Ramachary, Dhevalapally B.
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supporting information
p. 2897 - 2901
(2020/04/15)
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- Palladium-Catalyzed [5 + 2] Annulation of Vinylethylene Carbonates with Barbiturate-Derived Alkenes
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A palladium/XantPhos-catalyzed [5 + 2] annulation of VECs with electron-deficient alkenes having an isolated carbon-carbon double bond has been developed to afford spirobarbiturate-tetrahydrooxepines. This study provides an expedient assembly of biologically interesting spirobarbiturate-tetrahydrooxepines. The easy scalability and versatile transformability of the reaction products were also exhibited.
- Chen, Yuehua,Deng, Hao,Gao, Xing,Guo, Hongchao,Jiang, Feng,Wang, Wei,Wu, Yongjun,Zhu, Dongyu
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supporting information
p. 7158 - 7163
(2020/10/02)
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- NEGATIVE PHOTOCHROMIC MATERIALS WITH TUNABLE PROPERTIES
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Embodiments of the present disclosure describe a negative photochromatic material. Embodiments of the present disclosure further describe a method of tuning a negative photochromatic material comprising selecting an amine donor group, selecting an acceptor group, and contacting at least the selected amine donor group and the selected acceptor group to form a negative photochromatic material, wherein one or more of the selected amine donor group and the selected acceptor group tune at least an absorption range of the negative photochromatic material.
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- Synthesis of a novel tetracationic acidic organic salt based on DABCO and its applications as catalyst in the Knoevenagel condensation reactions in water
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Synthesis of a novel tetracationic acidic organic salt based on DABCO containing two sulfonic acid groups in the skeleton and four hydrogensulfate groups as counterion is described. Its catalytic efficiency in the Knoevenagel condensation of aldehydes wit
- Ziyaei Halimehjani, Azim,Barati, Vahid,Karimi, Mahshad
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supporting information
p. 724 - 734
(2019/02/13)
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- Photochromic compound and preparation method and application thereof
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The invention discloses a photochromic compound. The structure of the photochromic compound is represented by a formula A (shown in the description), wherein R represents a fluorescence group and represents substituted or unsubstituted naphthalene, anthracene, xanthenes, pyrene 1,8-naphthalimide, coumarin or pyran nitrile, and a substituent group on R is C1-C4 alkyl, halogen, hydroxide radical, C1-C4 alkoxy or C1-C4 alkyl amino; X represents oxygen, and Y represents C(CH3)2; or X represents N(CH3), and Y represents C(O). The invention further discloses an isomer of the photochromic compound, a mixture of the photochromic compound and the isomer and a preparation method and an application of the photochromic compound. The maximum absorption wavelength of a color-changing group of the photochromic compound is in a visible light region, but the maximum absorption wavelength of the fluorescence group is in an ultraviolet region and a near visible light region, so that the overlapping of the maximum absorption wavelengths of the two groups is effectively avoided. The photochromic compound has remarkable and special absorption and emitting properties in the ultraviolet region and the visible light region and can be used for producing photochromic fluorescence switches and molecular logic gates.
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Paragraph 0060; 0065; 0066
(2017/09/01)
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- Unraveling the Photoswitching Mechanism in Donor-Acceptor Stenhouse Adducts
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Molecular photoswitches have opened up a myriad of opportunities in applications ranging from responsive materials and control of biological function to molecular logics. Here, we show that the photoswitching mechanism of donor-acceptor Stenhouse adducts (DASA), a recently reported class of photoswitches, proceeds by photoinduced Z-E isomerization, followed by a thermal, conrotatory 4π-electrocyclization. The photogenerated intermediate is manifested by a bathochromically shifted band in the visible absorption spectrum of the DASA. The identification of the role of this intermediate reveals a key step in the photoswitching mechanism that is essential to the rational design of switching properties via structural modification.
- Lerch, Michael M.,Wezenberg, Sander J.,Szymanski, Wiktor,Feringa, Ben L.
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supporting information
p. 6344 - 6347
(2016/06/09)
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- Asymmetric Construction of Highly Functionalized Spirobarbiturate-Cyclopentenes through Chiral Phosphine-Catalyzed [3+2] Annulation of Morita–Baylis–Hillman Carbonates with Barbiturate-Derived Alkenes
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A multifunctional chiral phosphine-catalyzed enantioselective [3+2] annulation of Morita–Baylis–Hillman carbonates with barbiturate-derived alkenes has been achieved under mild conditions, providing a variety of chiral spirobarbiturate-cyclopentenes in moderate to excellent yields with moderate to excellent diastereo- and enantioselectivities. (Figure presented.).
- Liu, Yang,Yang, Wenjun,Wu, Yang,Mao, Biming,Gao, Xing,Liu, Honglei,Sun, Zhanhu,Xiao, Yumei,Guo, Hongchao
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supporting information
p. 2867 - 2872
(2016/09/16)
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- Tunable Visible and Near Infrared Photoswitches
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A class of tunable visible and near-infrared donor-acceptor Stenhouse adduct (DASA) photoswitches were efficiently synthesized in two to four steps from commercially available starting materials with minimal purification. Using either Meldrum's or barbitu
- Hemmer, James R.,Poelma, Saemi O.,Treat, Nicolas,Page, Zachariah A.,Dolinski, Neil D.,Diaz, Yvonne J.,Tomlinson, Warren,Clark, Kyle D.,Hooper, Joseph P.,Hawker, Craig,Read De Alaniz, Javier
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p. 13960 - 13966
(2016/11/06)
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- Photoswitching using visible light: A new class of organic photochromic molecules
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A versatile new class of organic photochromic molecules that offers an unprecedented combination of physical properties including tunable photoswitching using visible light, excellent fatigue resistance, and large polarity changes is described. These uniq
- Helmy, Sameh,Leibfarth, Frank A.,Oh, Saemi,Poelma, Justin E.,Hawker, Craig J.,De Alaniz, Javier Read
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supporting information
p. 8169 - 8172
(2014/06/24)
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- Reaction of 6-aminouracils with aldehydes in water as both solvent and reactant under FeCl3·6H2O catalysis: Towards 5-alkyl/arylidenebarbituric acids
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5-Alkyl/arylidenebarbituric acids were efficiently synthesized through an FeCl3·6H2O catalyzed domino reaction of 6-aminouracils, water and aldehydes with water serving a dual role as both solvent and reactant, under benign reaction conditions. A study on comparative substrate scope of 6-aminouracil versus barbituric acid showed similar efficacy towards 5-alkyl/arylidenebarbituric acids. The protocol is the first detailed report to prepare regioselectively 5-alkyl/arylidenebarbituric acids starting from 6-aminouracils, which is an alternative and competing strategy to hitherto all known reactions directly employing barbituric acids. the Partner Organisations 2014.
- Kalita, Subarna Jyoti,Mecadon, Hormi,Chandra Deka, Dibakar
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p. 32207 - 32213
(2014/08/18)
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- Design and synthesis of donor-acceptor stenhouse adducts: A visible light photoswitch derived from furfural
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The development of an easily synthesized, modular, and tunable organic photoswitch that responds to visible light has been a long-standing pursuit. Herein we provide a detailed account of the design and synthesis of a new class of photochromes based on fu
- Helmy, Sameh,Oh, Saemi,Leibfarth, Frank A.,Hawker, Craig J.,Read De Alaniz, Javier
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supporting information
p. 11316 - 11329
(2015/02/19)
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- Synthesis of fused uracils: Pyrano[2,3-d]pyrimidines and 1,4-bis(pyrano[2,3-d]pyrimidinyl)benzenes by domino Knoevenagel/Diels-Alder reactions
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Knoevenagel condensation of barbituric acids with aromatic aldehydes containing one or two formyl groups was carried out. 5-Arylidenebarbituric acids underwent smooth hetero-Diels-Alder (HDA) reactions with enol ethers to afford cis and trans diastereoisomers of pyr-ano[2,3-d]pyrimidine-2,4-diones and 5,5′-(1,4-phenylene)-bis[2H-pyrano[2,3-d]pyrimidine-2,4(3H)-dione] derivatives in excellent yields (75-88%). Syntheses were realized by Knoevenagel condensation and HDA reaction in four different reaction conditions: Knoevenagel condensation in water and Diels-Alder reaction in methylene chloride solution, Knoevenagel condensation in water and Diels-Alder reaction without solvent, three-component one-pot reaction in methylene chloride solution, or three-component one-pot reaction in water. All reactions were carried out without catalyst at room temperature. The reactions of malononitrile with Knoevenagel condensation products of barbituric acids and heteroaromatic aldehydes or terephthalaldehyde were examined and did not provide corresponding pyranopyrimidines.
- Palasz, Aleksandra
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scheme or table
p. 1175 - 1185
(2012/10/07)
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- New strategy for the synthesis of 5-Aryl-1H,1′H-spiro[furo[2,3-d] pyrimidine-6,5′-pyrimidine]2,2′,4,4′,6′(3H,3'H,5H) -pentaones and their sulfur analogues
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Reaction of barbituric acid (BA), 1,3-dimethyl barbituric acid (DMBA) and 2-thiobarbituric acid (TBA) with cyanogen bromide and aldehydes in the presence of L-(+)-tartaric acid afforded a new route for the synthesis of stable heterocyclic 5-aryl-1H,1′H-spiro[furo[2,3-d]pyrimidine-6,5′- pyrimidine]2,2′,4,4′,6′(3H,3′H,5H)- pentaones which is a dimeric form of barbiturate (uracil and thiouracil derivative). In the reaction of 1,3-diethyl thiobarbituric acid (DETBA) the Knoevenagel condensation and then Michael adducts were obtained under the same condition. Structure elucidation is carried out by 1H NMR, 13C NMR, FT-IR and Mass analyses. Mechanism of the formation is discussed.
- Jalilzadeh, Mohammad,Pesyan, Nader Noroozi
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experimental part
p. 3382 - 3388
(2012/01/19)
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- A green approach to the synthesis of fused uracils: Pyrano[2,3-d] pyrimidines. On-water one-pot synthesis by domino Knoevenagel/Diels-Alder reactions
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On-water Knoevenagel condensations of 2-thiobarbituric acid and N,N-dimethylbarbituric acid with aromatic and heteroaromatic aldehydes were carried out without a catalyst and at room temperature. Condensations in aqueous suspensions occurred rapidly, giving excellent yields. Solvent-free hetero-Diels-Alder reactions of 5-arylidene derivatives of barbituric acids with ethyl vinyl ether were investigated at room temperature and pyrano[2,3-d]pyrimidines of potential pharmacological activity were obtained in excellent yields. Three-component one-pot syntheses of annulated uracils were performed in aqueous suspensions. Reactions of barbituric acids, aldehydes, and ethyl vinyl ether were carried out at ambient temperature, whereas the one-pot synthesis with barbituric acids, aldehydes, and styrene or N-vinyl-2- oxazolidinone required the heating of aqueous suspensions at 60°C. On-water cycloadditions were characterized by high diastereoselectivity in contrast to reactions carried out in homogeneous organic media (dichloromethane, toluene). They allowed the cis adducts to be obtained preferentially or exclusively. The presented green methods avoid the use of catalysts, the heating of reaction mixtures for long times at high temperatures, and the use of organic solvents, and make the synthesis of a variety of pyrano[2,3-d]pyrimidines chemically efficient. The results reveal water as the medium of choice for the examined cycloadditions. Georg Thieme Verlag Stuttgart - New York.
- Paasz, Aleksandra
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experimental part
p. 4021 - 4032
(2011/02/21)
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- A novel, one-pot, efficient synthesis of 2-aroyl-1,4-diaryl-7,9-dimethyl-7, 9-diazaspiro[4.5]deca-1,3-diene-6,8,10-triones
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A novel and efficient synthesis of 2-aroyl-1,4-diaryl-7,9-dimethyl-7,9- diazaspiro[4.5]deca-1,3-diene-6,8,10-triones is described. The reactive 1:1 zwitterionic intermediate, formed by the addition of triphenylphosphine to diaroylacetylenes, was trapped by a Knoevenagel condensation product prepared in situ by reaction of AyV-dimethylbarbituric acid and aromatic aldehydes, to afford the title compounds in excellent yields under mild reaction conditions.
- Adib, Mehdi,Sayahi, Mohammad Hosein,Ziyadi, Hakimeh,Zhu, Long-Guan,Bijanzadeh, Hamid Reza
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experimental part
p. 3289 - 3294
(2009/05/11)
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- Three-component one-pot synthesis of fused uracils - Pyrano[2,3-d]- pyrimidine-2,4-diones
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5-Arylidene-N,N-dimethylbarbituric acids undergo smooth hetero-Diels-Alder reactions with enol ethers to afford cis and trans diastereoisomers of 7-alkoxy-5-aryl-2H-pyrano[2,3-d]pyrimidine-2,4-diones in excellent yields (84-95%). Cycloadducts with cis-configuration were the major products. Three-component one-pot reactions of N,N-dimethylbarbituric acid, aromatic and heteroaromatic aldehydes, and enol ethers in the presence of piperidine gave uracils also in very good yields (87-95%). The structure of the cycloadducts is discussed in terms of configuration and preferred conformation.
- Palasz, Aleksandra
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body text
p. 1397 - 1404
(2009/12/05)
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- 5-Arylidene 1,3-Dimethylbarbituric Acid Derivatives, Mild Organic Oxidants for Allylic and Benzylic Alcohols
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Various 5-arylidene 1,3-dimethylbarbituric acid derivatives and closely related compounds were synthesized as models of redox coenzymes and used for oxidation of alcohols.Under mild neutral conditions, 5-arylidene 1,3-dimethylbarbituric acid derivatives, especially those having an electron-withdrawing group on the aromatic ring, effectively oxidized allylic and benzylic alcohols to the corresponding carbonyl compounds.The relationship between the oxidizing ability and the structure of the oxidant (coenzyme model) was investigated and it was found that the electron density on the carbon-carbon double bond is a critical factor for the oxidation.In the case of the deuterium-labeled compound, the observed value of normal and primary isotope effect was 3.3 and so it was concluded that mechanism of this oxidation mainly involves the hydride transfer from the alcohol.An electrochemical investigation was also carried out and the redox potentials of the coenzyme models, 5-arylidene 1,3-dimethylbarbituric acid derivatives and related compounds, were measured.Keywords - 5-arylidene 1,3-dimethylbarbituric acid; coenzyme model; oxidation; allylic alcohol; benzylic alcohol; oxidation mechanism; hydride transfer; primary isotope effect; cyclic voltammetry; redox potential
- Tanaka, Kiyoshi,Chen, Xing,Kimura, Teiji,Yoneda, Fumio
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