1
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Gallardo-Rosas D, Guevara-Vela JM, Rocha-Rinza T, Toscano RA, López-Cortés JG, Ortega-Alfaro MC. Structure and isomerization behavior relationships of new push-pull azo-pyrrole photoswitches. Org Biomol Chem 2024; 22:4123-4134. [PMID: 38700442 DOI: 10.1039/d4ob00417e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
A family of stilbenyl-azopyrroles compounds 2a-d and 3a-d was efficiently obtained via a Mizoroki-Heck C-C-type coupling reaction between 2-(4'-iodophenyl-azo)-N-methyl pyrrole (1a) and different vinyl precursors. The influence of the π-conjugated backbone and the effect of the pyrrole moiety were correlated with their optical properties. Studies via UV-Visible spectrophotometry revealed that the inclusion of EWG or EDG favors a red-shift of the main absorption band in these azo compounds compared with their non-substituted analogues. Furthermore, there is a clear influence between the half-life of the Z isomer formed by irradiation with white light and the push-pull behavior of the molecules. In several cases, the stilbenyl-azopyrroles led to the formation of J-type aggregates in binary MeOH : H2O solvents, which are of interest for water compatible applications.
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Affiliation(s)
- D Gallardo-Rosas
- Instituto de Ciencias Nucleares, UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Ciudad de México, Mexico.
| | - J M Guevara-Vela
- Departamento de Química Física Aplicada, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - T Rocha-Rinza
- Instituto de Química UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Cuidad de México, Mexico
| | - R A Toscano
- Instituto de Química UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Cuidad de México, Mexico
| | - J G López-Cortés
- Instituto de Química UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Cuidad de México, Mexico
| | - M C Ortega-Alfaro
- Instituto de Ciencias Nucleares, UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Ciudad de México, Mexico.
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2
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Sisodiya DS, Ali SM, Chattopadhyay A. Unexplored Isomerization Pathways of Azobis(benzo-15-crown-5): Computational Studies on a Butterfly Crown Ether. J Phys Chem A 2023; 127:7080-7093. [PMID: 37526572 DOI: 10.1021/acs.jpca.3c02363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Computational studies on trans → cis and cis → trans isomerizations of photoresponsive azobis(benzo-15-crown-5) have been reported in this work. The photoexcited ππ* state (S2) of the trans isomer relaxes through the planar S2 minimum and the planar S2/S1 conical intersection (both situated around 9 kcal/mol below the vertically excited S2 state) arising along the N═N stretching coordinate. The nπ* state (S1) of this isomer has both planar and rotated (clockwise and anticlockwise) minima, which may lead to a torsional conical intersection (S0/S1) geometry having a
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Affiliation(s)
- Dilawar Singh Sisodiya
- Department of Chemistry, Birla Institute of Technology and Science (BITS), Pilani, K.K. Birla Goa Campus, Zuarinagar 403726, India
| | - Sk Musharaf Ali
- Chemical Engineering Division, Bhabha Atomic Research Centre (BARC), Mumbai 400085, India
| | - Anjan Chattopadhyay
- Department of Chemistry, Birla Institute of Technology and Science (BITS), Pilani, K.K. Birla Goa Campus, Zuarinagar 403726, India
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3
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Hiroyasu Y, Higashiguchi K, Shirakata C, Sugimoto M, Matsuda K. Kinetic Analysis of the Photochemical Paths in Asymmetric Diarylethene Dimer. Chemistry 2023; 29:e202300126. [PMID: 37246241 DOI: 10.1002/chem.202300126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 04/19/2023] [Accepted: 05/26/2023] [Indexed: 05/30/2023]
Abstract
An asymmetric diarylethene dimer composed of 2- and 3-thienylethene units linked by m-phenylene developed various colors upon UV irradiation via an independent photochromic reaction on each unit. The change in contents and the other photoresponses of the photogenerated four isomers were analyzed using quantum yield for all the possible photochemical paths, i. e., photoisomerization, fluorescence, energy transfer, and the other non-radiative paths. Almost all the rate constants of photochemical paths were calculated using measurable quantum yields and lifetimes. It was found that a significant contribution on photoresponse was the competition between photoisomerization and intramolecular energy transfer. The clear difference was observed in the photoresponses of the dimer and the 1 : 1 mixture solution of the model compounds. The m-phenylene spacer appropriately regulated the rate of energy transfer in the asymmetric dimer, and the spacer enabled isolation of the excited state of the dimer, making the above quantitative analysis possible.
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Affiliation(s)
- Yae Hiroyasu
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto, 615-8510, Japan
| | - Kenji Higashiguchi
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto, 615-8510, Japan
| | - Chihiro Shirakata
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto, 615-8510, Japan
| | - Masataka Sugimoto
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto, 615-8510, Japan
| | - Kenji Matsuda
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto, 615-8510, Japan
- Fukui Institute for Fundamental Chemistry, Kyoto University, Takano Nishibiraki-cho 34-4, Sakyo-ku, Kyoto, 606-8103, Japan
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4
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Kempfer-Robertson EM, Avdic I, Haase MN, Pike TD, Thompson LM. Protonation state control of electric field induced molecular switching mechanisms. Phys Chem Chem Phys 2023; 25:5251-5261. [PMID: 36723228 DOI: 10.1039/d2cp04494c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Scanning tunneling microscopy tip-induced deprotonation has been demonstrated experimentally and can be used as an additional control mechanism in electric-field induced molecular switching. The goal of the current work is to establish whether (de)protonation can be used to inhibit or enhance the electric field controlled thermal and photoisomerization processes. Dihydroxyazobenzene is used as a model system, where protonation/deprotonation of the free hydroxyl moiety changes the azo bond order, and so modifies the rate of electric field induced isomerization. Through the combined action of deprotonation and applied field, it was found that the cis-to-trans thermal isomerization barrier could be completely removed, changing the isomerization half-life from the order of several months. In addition, due to the presence of multiple isomerization mechanisms, electric fields could modify the isomerization kinetics by increasing the number of energetically viable isomerization pathways, rather than reducing the activation barrier of the lowest energy pathway. Excited state calculations indicated that the protonation state and electric field could be used together to control the presence of electronic degeneracies along the rotation pathway between S0/S1, and along all three pathways between S1/S2. This work provides insight into the mechanisms that enable the use of protonation state, light, and electric fields in concert to control molecular switches.
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Affiliation(s)
| | - Irma Avdic
- Department of Chemistry, University of Louisville, Louisville, Kentucky 40208, USA.
| | - Meagan N Haase
- Department of Chemistry, University of Louisville, Louisville, Kentucky 40208, USA.
| | - Thomas Dane Pike
- Department of Chemistry, University of Louisville, Louisville, Kentucky 40208, USA.
| | - Lee M Thompson
- Department of Chemistry, University of Louisville, Louisville, Kentucky 40208, USA.
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5
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Obloy LM, El-Khoury PZ, Tarnovsky AN. Excited-State-Selective Ultrafast Relaxation Dynamics and Photoisomerization of trans-4,4'-Azopyridine. J Phys Chem Lett 2022; 13:10863-10870. [PMID: 36384033 DOI: 10.1021/acs.jpclett.2c02523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Excited-state dynamics of trans-4,4'-azopyridine in ethanol is studied using femtosecond transient absorption with 30 fs temporal resolution. Exciting the system at three different wavelengths, 460 and 290 (275) nm, to access the S1 nπ* and S2 ππ* electronic states, respectively, reveals a 195 cm-1 vibrational coherence, which suggests that the same mode is active in both nπ* and ππ* relaxation channels. Following S1-excitation, relaxation proceeds via a nonrotational pathway, where a fraction of the nπ* population is trapped in a planar minimum (lifetime, 2.1 ps), while the remaining population travels further to a second shallow minimum (lifetime, 300 fs) prior to decay into the ground state. Population of the S2 state leads to 30 fs nonrotational relaxation with a concurrent buildup of nπ* population and nearly simultaneous formation of hot ground-state species. An increase in the cis-isomer quantum yield upon ππ* versus nπ* excitation is observed, which is opposite to trans-azobenzene.
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Affiliation(s)
- Laura M Obloy
- Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, United States
| | - Patrick Z El-Khoury
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Alexander N Tarnovsky
- Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, United States
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6
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Sah C, Mahadevan A, Kumar P, Venkataramani S. The curious case of the photochemistry of 2-hydroxyphenylazo-3,5-dimethylisoxazole: Unravelling the process among tautomer-ization, photoisomerization, and conformational changes. Phys Chem Chem Phys 2022; 24:7848-7855. [DOI: 10.1039/d1cp05344b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photoswitching in azo compounds is well established. Typically, the planar trans molecule (native) can undergo isomerization to cis isomer and vice versa in solution by light. However, observing such photochemistry...
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7
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Zheng Y, Zhou Y, Zhang Y, Deng P, Zhao X, Jiang S, Du G, Shen X, Xie X, Su Z, Yu Z. Water-Involved Ring-Opening of 4-Phenyl-1,2,4-triazoline-3,5-dione for "Photo-Clicked" Access to Carbamoyl Formazan Photoswitches In Situ. Chem Asian J 2021; 17:e202101239. [PMID: 34851039 DOI: 10.1002/asia.202101239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 11/23/2021] [Indexed: 11/08/2022]
Abstract
Cyclic azodicarbonyl derivatives, particularly 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD), commonly serve as arenophile, dienophile, enophile and electrophile. Perplexed by its instability in aqueous environment, there are few studies focused on the transient intermediate produced by hydrolysis of PTAD to achieve synthetic significance. Herein, we describe a "photo-click" method that involves nitrile imine (NI) from diarylsydnone to capture the diazenecarbonyl-phenyl-carbamic acid (DACPA) generated by water-promoted ring-opening of PTAD. DFT calculation reveal that H-bonding interactions between PTAD and water are vital to form DACPA which exhibited an umpolung effect during ligation by nature bond orbit (NBO) analysis. The ultra-fast ligation resulted in carbamoyl formazans, as a unique Z↔E photo-switchable linker on target molecules, including peptide and drugs, with excellent anti-fatigue performance. This strategy is showcased to construct highly functionalized carbamoyl formazans in situ for photo-pharmacology and material studies, which also expands the chemistry of PTAD in aqueous media.
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Affiliation(s)
- Yuanqin Zheng
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Yuqiao Zhou
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Yan Zhang
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Pengchi Deng
- Analytical & Testing Center, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Xiaohu Zhao
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Shichao Jiang
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Guangxi Du
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Xin Shen
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Xinyu Xie
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Zhishan Su
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Zhipeng Yu
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
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8
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Abstract
Azobenzenes are archetypal molecules that have a central role in fundamental and applied research. Over the course of almost two centuries, the area of azobenzenes has witnessed great achievements; azobenzenes have evolved from simple dyes to 'little engines' and have become ubiquitous in many aspects of our lives, ranging from textiles, cosmetics, food and medicine to energy and photonics. Despite their long history, azobenzenes continue to arouse academic interest, while being intensively produced for industrial purposes, owing to their rich chemistry, versatile and straightforward design, robust photoswitching process and biodegradability. The development of azobenzenes has stimulated the production of new coloured and light-responsive materials with various applications, and their use continues to expand towards new high-tech applications. In this Review, we highlight the latest achievements in the synthesis of red-light-responsive azobenzenes and the emerging application areas of photopharmacology, photoswitchable adhesives and biodegradable materials for drug delivery. We show how the synthetic versatility and adaptive properties of azobenzenes continue to inspire new research directions, with limits imposed only by one's imagination.
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9
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Bokare A, Arif J, Erogbogbo F. Strategies for Incorporating Graphene Oxides and Quantum Dots into Photoresponsive Azobenzenes for Photonics and Thermal Applications. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:2211. [PMID: 34578524 PMCID: PMC8467028 DOI: 10.3390/nano11092211] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 08/17/2021] [Accepted: 08/23/2021] [Indexed: 12/19/2022]
Abstract
Graphene represents a new generation of materials which exhibit unique physicochemical properties such as high electron mobility, tunable optics, a large surface to volume ratio, and robust mechanical strength. These properties make graphene an ideal candidate for various optoelectronic, photonics, and sensing applications. In recent years, numerous efforts have been focused on azobenzene polymers (AZO-polymers) as photochromic molecular switches and thermal sensors because of their light-induced conformations and surface-relief structures. However, these polymers often exhibit drawbacks such as low photon storage lifetime and energy density. Additionally, AZO-polymers tend to aggregate even at moderate doping levels, which is detrimental to their optical response. These issues can be alleviated by incorporating graphene derivatives (GDs) into AZO-polymers to form orderly arranged molecules. GDs such as graphene oxide (GO), reduced graphene oxide (RGO), and graphene quantum dots (GQDs) can modulate the optical response, energy density, and photon storage capacity of these composites. Moreover, they have the potential to prevent aggregation and increase the mechanical strength of the azobenzene complexes. This review article summarizes and assesses literature on various strategies that may be used to incorporate GDs into azobenzene complexes. The review begins with a detailed analysis of structures and properties of GDs and azobenzene complexes. Then, important aspects of GD-azobenzene composites are discussed, including: (1) synthesis methods for GD-azobenzene composites, (2) structure and physicochemical properties of GD-azobenzene composites, (3) characterization techniques employed to analyze GD-azobenzene composites, and most importantly, (4) applications of these composites in various photonics and thermal devices. Finally, a conclusion and future scope are given to discuss remaining challenges facing GD-azobenzene composites in functional science engineering.
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Affiliation(s)
| | | | - Folarin Erogbogbo
- Department of Biomedical Engineering, San José State University, 1 Washington Square, San José, CA 95112, USA; (A.B.); (J.A.)
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10
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Vela S, Scheidegger A, Fabregat R, Corminboeuf C. Tuning the Thermal Stability and Photoisomerization of Azoheteroarenes through Macrocycle Strain*. Chemistry 2021; 27:419-426. [PMID: 32991023 PMCID: PMC7839710 DOI: 10.1002/chem.202003926] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 09/27/2020] [Indexed: 11/24/2022]
Abstract
Azobenzene and its derivatives are one of the most widespread molecular scaffolds used in a range of modern applications, as well as in fundamental research. After photoexcitation, azo-based photoswitches revert back to the most stable isomer on a timescale ( t 1 / 2 ) that determines the range of potential applications. Attempts to bring t 1 / 2 to extreme values prompted the development of azobenzene and azoheteroarene derivatives that either rebalance the E- and Z-isomer stabilities, or exploit unconventional thermal isomerization mechanisms. In the former case, one successful strategy has been the creation of macrocycle strain, which tends to impact the E/Z stability asymmetrically, and thus significantly modifyt 1 / 2 . On the bright side, bridged derivatives have shown an improved optical switching owing to the higher quantum yields and absence of degradation. However, in most (if not all) cases, bridged derivatives display a reversed thermal stability (more stable Z-isomer), and smaller t 1 / 2 than the acyclic counterparts, which restricts their potential interest to applications requiring a fast forward and backwards switch. In this paper, the impact of alkyl bridges on the thermal stability of phenyl-azoheteroarenes is investigated by using computational methods, and it is revealed that it is indeed possible to combine such improved photoswitching characteristics while preserving the regular thermal stability (more stable E-isomer), and increased t 1 / 2 values under the appropriate connectivity and bridge length.
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Affiliation(s)
- Sergi Vela
- Institute of Chemical Sciences and EngineeringLaboratory for Computational Molecular DesignÉcole Polytechnique Fédérale de Lausanne (EPFL)1015LausanneSwitzerland
| | - Alan Scheidegger
- Institute of Chemical Sciences and EngineeringLaboratory for Computational Molecular DesignÉcole Polytechnique Fédérale de Lausanne (EPFL)1015LausanneSwitzerland
| | - Raimon Fabregat
- Institute of Chemical Sciences and EngineeringLaboratory for Computational Molecular DesignÉcole Polytechnique Fédérale de Lausanne (EPFL)1015LausanneSwitzerland
| | - Clémence Corminboeuf
- Institute of Chemical Sciences and EngineeringLaboratory for Computational Molecular DesignÉcole Polytechnique Fédérale de Lausanne (EPFL)1015LausanneSwitzerland
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11
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Vela S, Corminboeuf C. The Photoisomerization Pathway(s) of Push-Pull Phenylazoheteroarenes*. Chemistry 2020; 26:14724-14729. [PMID: 32692427 PMCID: PMC7756763 DOI: 10.1002/chem.202002321] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 07/17/2020] [Indexed: 12/31/2022]
Abstract
Azoheteroarenes are the most recent derivatives targeted to further improve the properties of azo-based photoswitches. Their light-induced mechanism for trans-cis isomerization is assumed to be very similar to that of the parent azobenzene. As such, they inherited the controversy about the dominant isomerization pathway (rotation vs. inversion) depending on the excited state (nπ* vs. ππ*). Although the controversy seems settled in azobenzene, the extent to which the same conclusions apply to the more structurally diverse family of azoheteroarenes is unclear. Here, by means of non-adiabatic molecular dynamics, the photoisomerization mechanism of three prototypical phenyl-azoheteroarenes with increasing push-pull character is unraveled. The evolution of the rotational and inversion conical intersection energies, the preferred pathway, and the associated kinetics upon both nπ* and ππ* excitations can be linked directly with the push-pull substitution effects. Overall, the working conditions of this family of azo-dyes is clarified and a possibility to exploit push-pull substituents to tune their photoisomerization mechanism is identified, with potential impact on their quantum yield.
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Affiliation(s)
- Sergi Vela
- Institute of Chemical Sciences and EngineeringLaboratory for Computational Molecular DesignÉcole Polytechnique Fédérale de Lausanne (EPFL)1015LausanneSwitzerland
| | - Clémence Corminboeuf
- Institute of Chemical Sciences and EngineeringLaboratory for Computational Molecular DesignÉcole Polytechnique Fédérale de Lausanne (EPFL)1015LausanneSwitzerland
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12
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Heindl AH, Wegner HA. Rational Design of Azothiophenes-Substitution Effects on the Switching Properties. Chemistry 2020; 26:13730-13737. [PMID: 32330338 PMCID: PMC7702042 DOI: 10.1002/chem.202001148] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Indexed: 12/22/2022]
Abstract
A series of substituted azothiophenes was prepared and investigated toward their isomerization behavior. Compared to azobenzene (AB), the presented compounds showed red-shifted absorption and almost quantitative photoisomerization to their (Z) states. Furthermore, it was found that electron-withdrawing substitution on the phenyl moiety increases, while electron-donating substitution decreases the thermal half-lives of the (Z)-isomers due to higher or lower stabilization by a lone pair-π interaction. Additionally, computational analysis of the isomerization revealed that a pure singlet state transition state is unlikely in azothiophenes. A pathway via intersystem crossing to a triplet energy surface of lower energy than the singlet surface provided a better fit with experimental data of the (Z)→(E) isomerization. The insights gained in this study provide the necessary guidelines to design effective thiophenylazo-photoswitches for applications in photopharmacology, material sciences, or solar energy harvesting applications.
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Affiliation(s)
- Andreas H. Heindl
- Institute of Organic ChemistryJustus Liebig UniversityHeinrich-Buff-Ring 1735392GiessenGermany
- Center for Material Research (LaMa)Justus Liebig UniversityHeinrich-Buff-Ring 1635392GiessenGermany
| | - Hermann A. Wegner
- Institute of Organic ChemistryJustus Liebig UniversityHeinrich-Buff-Ring 1735392GiessenGermany
- Center for Material Research (LaMa)Justus Liebig UniversityHeinrich-Buff-Ring 1635392GiessenGermany
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13
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Čechová L, Filo J, Dračínský M, Slavov C, Sun D, Janeba Z, Slanina T, Wachtveitl J, Procházková E, Cigáň M. Polysubstituted 5‐Phenylazopyrimidines: Extremely Fast Non‐ionic Photochromic Oscillators. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202007065] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Lucie Čechová
- Institute of Organic Chemistry and Biochemistry Czech Academy of Sciences Flemingovo nám. 2 16610 Prague Czech Republic
| | - Juraj Filo
- Institute of Chemistry Comenius University Ilkovičova 6 84215 Bratislava Slovakia
| | - Martin Dračínský
- Institute of Organic Chemistry and Biochemistry Czech Academy of Sciences Flemingovo nám. 2 16610 Prague Czech Republic
| | - Chavdar Slavov
- Institute of Physical and Theoretical Chemistry Goethe University Max-von-Laue Straße 7 60438 Frankfurt am Main Germany
| | - Dazhong Sun
- Institute of Physical and Theoretical Chemistry Goethe University Max-von-Laue Straße 7 60438 Frankfurt am Main Germany
| | - Zlatko Janeba
- Institute of Organic Chemistry and Biochemistry Czech Academy of Sciences Flemingovo nám. 2 16610 Prague Czech Republic
| | - Tomáš Slanina
- Institute of Organic Chemistry and Biochemistry Czech Academy of Sciences Flemingovo nám. 2 16610 Prague Czech Republic
| | - Josef Wachtveitl
- Institute of Physical and Theoretical Chemistry Goethe University Max-von-Laue Straße 7 60438 Frankfurt am Main Germany
| | - Eliška Procházková
- Institute of Organic Chemistry and Biochemistry Czech Academy of Sciences Flemingovo nám. 2 16610 Prague Czech Republic
| | - Marek Cigáň
- Institute of Chemistry Comenius University Ilkovičova 6 84215 Bratislava Slovakia
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14
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Čechová L, Filo J, Dračínský M, Slavov C, Sun D, Janeba Z, Slanina T, Wachtveitl J, Procházková E, Cigáň M. Polysubstituted 5-Phenylazopyrimidines: Extremely Fast Non-ionic Photochromic Oscillators. Angew Chem Int Ed Engl 2020; 59:15590-15594. [PMID: 32433814 DOI: 10.1002/anie.202007065] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Indexed: 11/09/2022]
Abstract
Photochromic systems with an ultrahigh rate of thermal relaxation are highly desirable for the development of new efficient photochromic oscillators. Based on DFT calculations, we designed a series of 5-phenylazopyrimidines with strong push-pull character in silico and observed very low energy barriers for the thermal (Z)-to-(E) isomerization. The structure of the (Z)-isomer of the slowest isomerizing derivative in the series was confirmed by NMR analysis with in situ irradiation at low temperature. The substituents can tune the lifetime of thermal back isomerization from hundreds of microseconds to several nanoseconds (8 orders of magnitude). The photoswitching parameters were extracted from transient absorption techniques and a dominant rotation mechanism of the (Z)-to-(E) thermal fading was proposed based on DFT calculations.
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Affiliation(s)
- Lucie Čechová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 16610, Prague, Czech Republic
| | - Juraj Filo
- Institute of Chemistry, Comenius University, Ilkovičova 6, 84215, Bratislava, Slovakia
| | - Martin Dračínský
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 16610, Prague, Czech Republic
| | - Chavdar Slavov
- Institute of Physical and Theoretical Chemistry, Goethe University, Max-von-Laue Straße 7, 60438, Frankfurt am Main, Germany
| | - Dazhong Sun
- Institute of Physical and Theoretical Chemistry, Goethe University, Max-von-Laue Straße 7, 60438, Frankfurt am Main, Germany
| | - Zlatko Janeba
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 16610, Prague, Czech Republic
| | - Tomáš Slanina
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 16610, Prague, Czech Republic
| | - Josef Wachtveitl
- Institute of Physical and Theoretical Chemistry, Goethe University, Max-von-Laue Straße 7, 60438, Frankfurt am Main, Germany
| | - Eliška Procházková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 16610, Prague, Czech Republic
| | - Marek Cigáň
- Institute of Chemistry, Comenius University, Ilkovičova 6, 84215, Bratislava, Slovakia
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15
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Balam-Villarreal JA, López-Mayorga BJ, Gallardo-Rosas D, Toscano RA, Carreón-Castro MP, Basiuk VA, Cortés-Guzmán F, López-Cortés JG, Ortega-Alfaro MC. π-Extended push-pull azo-pyrrole photoswitches: synthesis, solvatochromism and optical band gaps. Org Biomol Chem 2020; 18:1657-1670. [PMID: 32048680 DOI: 10.1039/c9ob02410g] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new family of push-pull biphenyl-azopyrrole compounds 3b-g and 4b-d was efficiently obtained via a Suzuki cross-coupling reaction between 2-(4'-iodophenyl-azo)-N-methyl pyrrole (1a) or 3-(4'-iodophenyl-azo)-1,2,5-trimethyl pyrrole (2a) and 4'-substituted phenyl boronic acids in excellent yields. The influence of the π-biphenyl backbone and pyrrole pattern substitution was correlated with their optical properties. Solvatochromic studies via UV-visible spectrophotometry revealed that the inclusion of a 4'-nitro-biphenyl fragment favors a red-shift of the main absorption band in these azo compounds compared with their non-substituted analogues. Likewise, optical band-gaps were estimated by means of electronic absorption spectra and correlated with TD-DFT studies. The pyrrole pattern substitution and the π-conjugated backbone exhibit a clear influence on their thermal isomerization kinetics at room temperature. In all cases, biphenylazo-pyrrole compounds lead to the formation of J-type aggregates in binary MeOH : H2O solvents. Under these conditions, compounds 3b-c undergo a water-assisted cis-to-trans isomerization at room temperature.
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Affiliation(s)
- J A Balam-Villarreal
- Instituto de Ciencias Nucleares, UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Ciudad de México, Mexico.
| | - B J López-Mayorga
- Instituto de Ciencias Nucleares, UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Ciudad de México, Mexico.
| | - D Gallardo-Rosas
- Instituto de Ciencias Nucleares, UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Ciudad de México, Mexico.
| | - R A Toscano
- Instituto de Química UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Cuidad de México, Mexico.
| | - M P Carreón-Castro
- Instituto de Ciencias Nucleares, UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Ciudad de México, Mexico.
| | - V A Basiuk
- Instituto de Ciencias Nucleares, UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Ciudad de México, Mexico.
| | - F Cortés-Guzmán
- Instituto de Química UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Cuidad de México, Mexico.
| | - J G López-Cortés
- Instituto de Química UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Cuidad de México, Mexico.
| | - M C Ortega-Alfaro
- Instituto de Ciencias Nucleares, UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán C.P. 04510, Ciudad de México, Mexico.
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16
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Kennedy ADW, Sandler I, Andréasson J, Ho J, Beves JE. Visible‐Light Photoswitching by Azobenzazoles. Chemistry 2020; 26:1103-1110. [DOI: 10.1002/chem.201904309] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Indexed: 11/09/2022]
Affiliation(s)
| | - Isolde Sandler
- School of Chemistry UNSW Sydney Sydney NSW 2052 Australia
| | - Joakim Andréasson
- Department of Chemistry and Chemical Engineering Chalmers University of Technology 412 96 Göteborg Sweden
| | - Junming Ho
- School of Chemistry UNSW Sydney Sydney NSW 2052 Australia
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17
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Pithan PM, Kuhlmann C, Engelhard C, Ihmels H. Synthesis of 5-Alkyl- and 5-Phenylamino-Substituted Azothiazole Dyes with Solvatochromic and DNA-Binding Properties. Chemistry 2019; 25:16088-16098. [PMID: 31523866 PMCID: PMC6973281 DOI: 10.1002/chem.201903657] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 09/09/2019] [Indexed: 01/24/2023]
Abstract
A series of new 5-mono- and 5,5'-bisamino-substituted azothiazole derivatives was synthesized from the readily available diethyl azothiazole-4,4'-dicarboxylate. This reaction most likely comprises an initial Michael-type addition by the respective primary alkyl and aromatic amines at the carbon atom C5 of the substrate. Subsequently, the resulting intermediates are readily oxidized by molecular oxygen to afford the amino-substituted azothiazole derivatives. The latter exhibit remarkably red-shifted absorption bands (λabs =507-661 nm) with high molar extinction coefficients and show a strong positive solvatochromism. As revealed by spectrometric titrations and circular and linear dichroism studies, the water-soluble, bis-(dimethylaminopropylamino)-substituted azo dye associates with duplex DNA by formation of aggregates along the phosphate backbone at high ligand-DNA ratios (LDR) and by intercalation at low LDR, which also leads to a significant increase of the otherwise low emission intensity at 671 nm.
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Affiliation(s)
- Phil M. Pithan
- Department of Chemistry and Biology, and Center of Micro- and Nanochemistry and EngineeringUniversity of SiegenAdolf-Reichwein-Str. 257068SiegenGermany
| | - Christopher Kuhlmann
- Department of Chemistry and Biology, and Center of Micro- and Nanochemistry and EngineeringUniversity of SiegenAdolf-Reichwein-Str. 257068SiegenGermany
| | - Carsten Engelhard
- Department of Chemistry and Biology, and Center of Micro- and Nanochemistry and EngineeringUniversity of SiegenAdolf-Reichwein-Str. 257068SiegenGermany
| | - Heiko Ihmels
- Department of Chemistry and Biology, and Center of Micro- and Nanochemistry and EngineeringUniversity of SiegenAdolf-Reichwein-Str. 257068SiegenGermany
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18
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Maier MS, Hüll K, Reynders M, Matsuura BS, Leippe P, Ko T, Schäffer L, Trauner D. Oxidative Approach Enables Efficient Access to Cyclic Azobenzenes. J Am Chem Soc 2019; 141:17295-17304. [PMID: 31584272 DOI: 10.1021/jacs.9b08794] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Azobenzenes are versatile photoswitches that have found widespread use in a variety of fields, ranging from photopharmacology to the material sciences. In addition to regular azobenzenes, the cyclic diazocines have recently emerged. Although diazocines have fascinating conformational and photophysical properties, their use has been limited by their synthetic accessibility. Herein, we present a general, high-yielding protocol that relies on the oxidative cyclization of dianilines. In combination with a modular substrate synthesis, it allows for rapid access to diversely functionalized diazocines on gram scales. Our work systematically explores substituent effects on the photoisomerization and thermal relaxation of diazocines. It will enable their incorporation into a wide variety of functional molecules, unlocking the full potential of these emerging photoswitches. The method can be applied to the synthesis of a new cyclic azobenzene with a nine-membered central ring and distinct properties.
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Affiliation(s)
- Martin S Maier
- Department of Chemistry and Center for Integrated Protein Science (CIPSM) , Ludwig Maximilian University Munich , 81377 Munich , Germany.,Department of Chemistry , New York University , New York , New York 10003 , United States
| | - Katharina Hüll
- Department of Chemistry and Center for Integrated Protein Science (CIPSM) , Ludwig Maximilian University Munich , 81377 Munich , Germany.,Department of Chemistry , New York University , New York , New York 10003 , United States
| | - Martin Reynders
- Department of Chemistry and Center for Integrated Protein Science (CIPSM) , Ludwig Maximilian University Munich , 81377 Munich , Germany.,Department of Chemistry , New York University , New York , New York 10003 , United States
| | - Bryan S Matsuura
- Department of Chemistry and Center for Integrated Protein Science (CIPSM) , Ludwig Maximilian University Munich , 81377 Munich , Germany.,Department of Chemistry , New York University , New York , New York 10003 , United States
| | - Philipp Leippe
- Department of Chemistry and Center for Integrated Protein Science (CIPSM) , Ludwig Maximilian University Munich , 81377 Munich , Germany
| | - Tongil Ko
- Department of Chemistry , New York University , New York , New York 10003 , United States
| | - Lukas Schäffer
- Department of Chemistry and Center for Integrated Protein Science (CIPSM) , Ludwig Maximilian University Munich , 81377 Munich , Germany
| | - Dirk Trauner
- Department of Chemistry and Center for Integrated Protein Science (CIPSM) , Ludwig Maximilian University Munich , 81377 Munich , Germany.,Department of Chemistry , New York University , New York , New York 10003 , United States
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