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Pinjari D, Patil Y, Misra R. Near-Infrared Absorbing Aza-BODIPY Dyes for Optoelectronic Applications. Chem Asian J 2024:e202400167. [PMID: 38733151 DOI: 10.1002/asia.202400167] [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: 02/16/2024] [Revised: 05/04/2024] [Accepted: 05/07/2024] [Indexed: 05/13/2024]
Abstract
Organic dyes that absorb light in the visible to near-infrared region have garnered significant interest, owing to their extensive utility in organic photovoltaics and various biomedical applications. Aza-boron-dipyrromethene (Aza-BODIPY) dyes are a class of chromophores with impressive photophysical properties such as tunable absorption from the visible region towards near infrared (NIR) region, high molar absorptivity, and fluorescence quantum yield. In this review, we discuss the developments in the aza-BODIPYs, related to their synthetic routes, photophysical properties and their applications. Their design strategies, modifications in chemical structures, mode/position of attachment, and their impact on photo-physical properties are reviewed. The potential applications of aza-BODIPY derivatives such as organic solar cells, photodynamic therapy, boron-neutron capture therapy, fluorescence sensors, photo-redox catalysis, photoacoustic probes and optoelectronic devices are explained.
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Affiliation(s)
- Dilip Pinjari
- Department of Chemistry, Indian Institute of Technology Indore, Indore, 453552, India
| | - Yuvraj Patil
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota, 58108, United States
| | - Rajneesh Misra
- Department of Chemistry, Indian Institute of Technology Indore, Indore, 453552, India
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2
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Chen H, An N, Wang Y, Wang G, Mukherjee S, Bian H, Ma J, Liu J, Fang Y. Tracking the Intramolecular Charge Transfer Process of 2,6-Substituted D-A BODIPY Derivatives. J Phys Chem B 2023; 127:2044-2051. [PMID: 36847652 DOI: 10.1021/acs.jpcb.3c00347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
Three 2,6-electron donor-substituted boron dipyrromethene (BODIPY) exhibiting an intramolecular charge transfer (ICT) character with large Stokes shift and moderate fluorescence quantum yields were designed and synthesized. Broadband femtosecond transient absorption (fs-TA) spectroscopy measurements were performed to directly detect the CT state in nonpolar or less polar solvents and the charge separation (CS) state in more polar solvents. A solid foundation for the fs-TA assignment can be found in electrolysis experiments. In addition, the ICT character of the newly designed compounds was investigated by density functional theory (DFT) calculations. Meanwhile, the reference compounds without the donor groups were synthesized, and their photophysical behaviors and ultrafast time-resolved spectra confirmed that no ICT process occurred regardless of the nature of the solvent. This work emphasizes the importance of decorating the BODIPY core with electron-donating substituents at 2,6-positions to efficiently adjust its photofunctional behaviors demonstrating the ICT character. Importantly, the photophysical processes could be easily regulated by changing the solvent with different polarities.
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Affiliation(s)
- Hao Chen
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710062, People's Republic of China
| | - Nan An
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710062, People's Republic of China
| | - Yanqing Wang
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710062, People's Republic of China
| | - Gang Wang
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710062, People's Republic of China
| | - Somnath Mukherjee
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710062, People's Republic of China
| | - Hongtao Bian
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710062, People's Republic of China
| | - Jiani Ma
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710062, People's Republic of China
| | - Jing Liu
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710062, People's Republic of China
| | - Yu Fang
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710062, People's Republic of China
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Akhuseyin Yildiz E, Yabaş E, Sözmen F, Bozkurt Y, Karatay A, Boyacioglu B, Ünver H, Elmali A. Effects of Heavy Iodine Atoms and π-Expanded Conjugation on Charge Transfer Dynamics in Carboxylic Acid BODIPY Derivatives as Triplet Photosensitizers. Chemphyschem 2023; 24:e202200735. [PMID: 36377545 DOI: 10.1002/cphc.202200735] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 11/07/2022] [Accepted: 11/10/2022] [Indexed: 11/16/2022]
Abstract
Borondipyrromethene (BODIPY) chromophores are composed of a functional-COOH group at meso position with or without a biphenyl ring, and their compounds with heavy iodine atoms at -2, -6 positions of the BODIPY indacene core were synthesized. The photophysical properties of the compounds were studied with steady-state absorption and fluorescence measurements. It was observed that the absorption band is significantly red-shifted, and fluorescence signals are quenched in the presence of iodine atoms. In addition to that, it was indicated that the biphenyl ring does not affect the spectral shifting in the absorption as well as fluorescence spectra. In an attempt to investigate the effect of π-expanded biphenyl moieties and heavy iodine atoms on charge transfer dynamics, femtosecond transient absorption spectroscopy measurements were carried out in the environment of the tetrahydrofuran (THF) solution. Based on the performed ultrafast pump-probe spectroscopy, BODIPY compounds with iodine atoms lead to intersystem crossing (ISC) and ISC rates were determined as 150 ps and 180 ps for iodine BODIPY compounds with and without π-expanded biphenyl moieties, respectively. According to the theoretical results, the charge transfer in the investigated compounds mostly appears to be intrinsic local excitations, corresponding to high photoluminescence efficiency. These experimental findings are useful for the design and study of the fundamental photochemistry of organic triplet photosensitizers.
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Affiliation(s)
- Elif Akhuseyin Yildiz
- Department of Physics Engineering, Faculty of Engineering, Ankara University, 06100, Beşevler-Ankara, Türkiye
| | - Ebru Yabaş
- Advanced Technology Application and Research Center, Sivas Cumhuriyet University, 58140, Sivas, Türkiye
| | - Fazlı Sözmen
- Nanotechnology Engineering Department, Faculty of Engineering, Sivas Cumhuriyet University, 58140, Sivas, Türkiye
| | - Yasemin Bozkurt
- Department of Metallurgical and Materials Engineering, Sivas Cumhuriyet University, 58140, Sivas, Türkiye
| | - Ahmet Karatay
- Department of Physics Engineering, Faculty of Engineering, Ankara University, 06100, Beşevler-Ankara, Türkiye
| | - Bahadir Boyacioglu
- Vocational School of Health Services, Ankara University, 06290, Kecioren-Ankara, Türkiye
| | - Hüseyin Ünver
- Department of Physics, Faculty of Science, Ankara University, 06100, Besevler-Ankara, Türkiye
| | - Ayhan Elmali
- Department of Physics Engineering, Faculty of Engineering, Ankara University, 06100, Beşevler-Ankara, Türkiye
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Sonkaya Ö, Soylukan C, Pamuk Algi M, Algi F. Aza-BODIPY-based Fluorescent and Colorimetric Sensors and Probes. Curr Org Synth 2023; 20:20-60. [PMID: 35170414 DOI: 10.2174/1570179419666220216123033] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 11/30/2021] [Accepted: 12/18/2021] [Indexed: 12/16/2022]
Abstract
Aza-boron-dipyrromethenes (Aza-BODIPYs) represent an important class of chromophores absorbing and emitting in the near-infrared (NIR) region. They have unique optical and electronic features and higher physiological and photo stability than other NIR dyes. Especially after the development of facile synthetic routes, Aza-BODIPYs have become indispensable fluors that can find various applications ranging from chemosensors, bioimaging, phototherapy, solar energy materials, photocatalysis, photon upconversion, lasers, and optoelectronics. Herein, we review Aza-BODIPY based fluorescent and colorimetric chemosensors. We show the potential and untapped toolbox of Aza-BODIPY based fluorescent and colorimetric chemosensors. Hence, we divide the fluorescent and colorimetric chemosensors and probes into five sections according to the target analytes. The first section begins with the chemosensors developed for pH. Next, we discuss Aza-BODIPY based ion sensors, including metal ions and anions. Finally, we present the chemosensors and probes concerning reactive oxygen (ROS) and nitrogen species (RNS) along with biologically relevant species in the last two sections. We believe that Aza-BODIPYs are still in their infancy, and they have a promising future for translation from the bench to real biomedical and materials science applications. After two decades of intensive research, it seems that there are many more to come in this already fertile field. Overall, we hope that future work will further expand the applications of Aza-BODIPY in many areas.
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Affiliation(s)
- Ömer Sonkaya
- Department of Chemistry, Aksaray University, TR-68100 Aksaray, Turkey
- ASUBTAM Memduh Bilmez BioNanoTech Lab., Aksaray University, TR-68100 Aksaray, Turkey
| | - Caner Soylukan
- ASUBTAM Memduh Bilmez BioNanoTech Lab., Aksaray University, TR-68100 Aksaray, Turkey
- Department of Biotechnology & ASUBTAM Memduh Bilmez BioNanoTech Lab., Aksaray University, TR-68100 Aksaray, Turkey
| | - Melek Pamuk Algi
- Department of Chemistry, Aksaray University, TR-68100 Aksaray, Turkey
- ASUBTAM Memduh Bilmez BioNanoTech Lab., Aksaray University, TR-68100 Aksaray, Turkey
| | - Fatih Algi
- ASUBTAM Memduh Bilmez BioNanoTech Lab., Aksaray University, TR-68100 Aksaray, Turkey
- Department of Biotechnology & ASUBTAM Memduh Bilmez BioNanoTech Lab., Aksaray University, TR-68100 Aksaray, Turkey
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Near-infrared aza-BODIPYs bearing tetraphenylethylene: Synthesis, photophysical studies, and cell imaging application. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2022.114128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Gut A, Ciejka J, Makuszewski J, Majewska I, Brela M, Łapok Ł. Near-Infrared fluorescent unsymmetrical aza-BODIPYs: Synthesis, photophysics and TD-DFT calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 271:120898. [PMID: 35077984 DOI: 10.1016/j.saa.2022.120898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 01/09/2022] [Accepted: 01/12/2022] [Indexed: 06/14/2023]
Abstract
In view of the ever-growing demand for efficient NIR fluorophores for biomedical applications, we herein report the synthesis and properties of four unsymmetrical aza-BODIPYs exhibiting NIR fluorescence. Highly desirable photophysical and photochemical properties were induced in these molecules due to the presence of both strongly electron-withdrawing p-nitrophenyl rings (p-NO2Ph-) and mildly electron-donating p-methoxyphenyl rings (p-MeOPh-) within the aza-BODIPY core. In particular, upon excitation with λabs the unsymmetrical aza-BODIPYs studied exhibited NIR emission with λf ranging from 699 nm to 718 nm in toluene. The fluorescence quantum yields (Φf), depending on the substitution pattern, ranged from Φf = 0.49 to Φf = 0.22 and the fluorescence lifetimes ranged from τf = 1.90 ns to τf = 3.59 ns. Aza-BODIPY with electron-donating substituent at 3 position and electron-withdrawing substituent at 5 position was identified as cell permeable, NIR emitting fluorophore suitable for bioimaging.
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Affiliation(s)
- Arkadiusz Gut
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland.
| | - Justyna Ciejka
- Department of Engineering and Technology of Chemical Processes, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
| | - Jakub Makuszewski
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland
| | - Izabela Majewska
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland
| | - Mateusz Brela
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland
| | - Łukasz Łapok
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland
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Chang HJ, Bondar MV, Munera N, David S, Maury O, Berginc G, Le Guennic B, Jacquemin D, Andraud C, Hagan DJ, Van Stryland EW. Femtosecond Spectroscopy and Nonlinear Optical Properties of aza-BODIPY Derivatives in Solution. Chemistry 2022; 28:e202104072. [PMID: 35157336 DOI: 10.1002/chem.202104072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Indexed: 01/22/2023]
Abstract
The fast relaxation processes in the excited electronic states of functionalized aza-boron-dipyrromethene (aza-BODIPY) derivatives (1-4) were investigated in liquid media at room temperature, including the linear photophysical, photochemical, and nonlinear optical (NLO) properties. Optical gain was revealed for nonfluorescent derivatives 3 and 4 in the near infrared (NIR) spectral range under femtosecond excitation. The values of two-photon absorption (2PA) and excited-state absorption (ESA) cross-sections were obtained for 1-4 in dichloromethane using femtosecond Z-scans, and the role of bromine substituents in the molecular structures of 2 and 4 is discussed. The nature of the excited states involved in electronic transitions of these dyes was investigated using quantum-chemical TD-DFT calculations, and the obtained spectral parameters are in reasonable agreement with the experimental data. Significant 2PA (maxima cross-sections ∼2000 GM), and large ESA cross-sections ∼10-20 m2 of these new aza-BODIPY derivatives 1-4 along with their measured high photostability reveal their potential for photonic applications in general and optical limiting in particular.
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Affiliation(s)
- Hao-Jung Chang
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, FL, 32816, USA
| | - Mykhailo V Bondar
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, FL, 32816, USA.,Institute of Physics NASU, Prospect Nauki, 46, Kyiv-28, 03028, Ukraine
| | - Natalia Munera
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, FL, 32816, USA
| | - Sylvain David
- Univ. Lyon, ENS Lyon, CNRS UMR 5182, Laboratoire de Chimie, 46 Allée d'Italie, 69364, Lyon, France
| | - Olivier Maury
- Univ. Lyon, ENS Lyon, CNRS UMR 5182, Laboratoire de Chimie, 46 Allée d'Italie, 69364, Lyon, France
| | - Gerard Berginc
- Thales LAS France, 2 Avenue Gay Lussac, 78990, Élancourt, France
| | - Boris Le Guennic
- CNRS, Institut des Sciences Chimiques de Rennes UMR 6266, Université Rennes, 35000, Rennes, France
| | | | - Chantal Andraud
- Univ. Lyon, ENS Lyon, CNRS UMR 5182, Laboratoire de Chimie, 46 Allée d'Italie, 69364, Lyon, France
| | - David J Hagan
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, FL, 32816, USA
| | - Eric W Van Stryland
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, FL, 32816, USA
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Schäfer C, Mony J, Olsson T, Börjesson K. Effect of the Aza-N-Bridge and Push-Pull Moieties: A Comparative Study between BODIPYs and Aza-BODIPYs. J Org Chem 2022; 87:2569-2579. [PMID: 35188769 PMCID: PMC8902755 DOI: 10.1021/acs.joc.1c02525] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the field of fluorescent dyes, difluoroboron-dipyrromethenes (BODIPY) have a highly respected position. To predict their photophysical properties prior to synthesis and therefore to successfully design molecules specifically for one's needs, a solid structure-function understanding based on experimental observations is vital. This work delivers a photophysical evaluation of BODIPY and aza-BODIPY derivatives equipped with different electron-withdrawing/-donating substituents. Using combinatorial chemistry, pyrroles substituted with electron-donating/-withdrawing substituents were condensed together in two different manners, thus providing two sets of molecules. The only difference between the two sets is the bridging unit providing a so far lacking comparison between BODIPYs and aza-BODIPYs structural homologues. Replacing the meso-methine bridge with an aza-N bridge results in a red-shifted transition and considerably different, temperature-activated, excited-state relaxation pathways. The effect of electron-donating units on the absorption but not emission for BODIPYs was suppressed compared to aza-BODIPYs. This result could be evident in a substitution pattern-dependent Stokes shift. The outlook of this study is a deeper understanding of the structure-optics relationship of the (aza)-BODIPY-dye class, leading to an improvement in the de novo design of tailor-made molecules for future applications.
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Affiliation(s)
- Clara Schäfer
- Department of Chemistry and Molecular Biology, University of Gothenburg, Kemivägen 10, 41296 Gothenburg, Sweden
| | - Jürgen Mony
- Department of Chemistry and Molecular Biology, University of Gothenburg, Kemivägen 10, 41296 Gothenburg, Sweden
| | - Thomas Olsson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Kemivägen 10, 41296 Gothenburg, Sweden
| | - Karl Börjesson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Kemivägen 10, 41296 Gothenburg, Sweden
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David S, Chang HJ, Lopes C, Brännlund C, Le Guennic B, Berginc G, Van Stryland E, Bondar MV, Hagan D, Jacquemin D, Andraud C, Maury O. Benzothiadiazole-Substituted Aza-BODIPY Dyes: Two-Photon Absorption Enhancement for Improved Optical Limiting Performances in the Short-Wave IR Range. Chemistry 2021; 27:3517-3525. [PMID: 33330997 DOI: 10.1002/chem.202004899] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 12/10/2020] [Indexed: 12/13/2022]
Abstract
Aza-boron dipyrromethenes (aza-BODIPYs) presenting a benzothiadiazole substitution on upper positions are described. The strong electron-withdrawing effect of the benzothiadiazole moiety permits enhancement of the accepting strength and improves the delocalization of the aza-BODIPY core to attain a significant degree of electronic communication between the lower donating groups and the upper accepting groups. The nature of the intramolecular charge transfer is studied both experimentally and theoretically. Linear spectroscopy highlighted the strongly redshifted absorption and emission of the synthesized molecules with recorded fluorescence spectra over 1000 nm. Nonlinear optical properties were also investigated. Strong enhancement of the two-photon absorption of the substituted dyes compared with the unsubstituted one (up to 4520 GM at 1300 nm) results in an approximately 15-20 % improvement of the optical power limiting performances. These dyes are therefore a good starting point for further improvement of optical power limiting in the short-wave IR range.
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Affiliation(s)
- Sylvain David
- Laboratoire de Chimie, UMR 5182, ENS Lyon, CNRS, Université Lyon 1, 46 Allée d'Italie, 69364, Lyon, France
| | - Hao-Jung Chang
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, FL, 32816, USA
| | - Cesar Lopes
- Electrooptical Systems, Swedish Defense Research Agency (FOI), Linköping, 58111, Sweden
| | - Carl Brännlund
- Electrooptical Systems, Swedish Defense Research Agency (FOI), Linköping, 58111, Sweden
| | - Boris Le Guennic
- CNRS, Institut des Sciences Chimiques de Rennes UMR 6226, Université Rennes, 35000, Rennes, France
| | - Gérard Berginc
- Thales LAS France, 2 Avenue Gay Lussac, 78990, Élancourt, France
| | - Eric Van Stryland
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, FL, 32816, USA
| | - Mykailo V Bondar
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, FL, 32816, USA.,Institute of Physics NASU, Prospect Nauki, 46, Kyiv-28, 03028, Ukraine
| | - David Hagan
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, FL, 32816, USA
| | | | - Chantal Andraud
- Laboratoire de Chimie, UMR 5182, ENS Lyon, CNRS, Université Lyon 1, 46 Allée d'Italie, 69364, Lyon, France
| | - Olivier Maury
- Laboratoire de Chimie, UMR 5182, ENS Lyon, CNRS, Université Lyon 1, 46 Allée d'Italie, 69364, Lyon, France
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Łapok Ł, Cieślar I, Pędziński T, Stadnicka KM, Nowakowska M. Near-Infrared Photoactive Aza-BODIPY: Thermally Robust and Photostable Photosensitizer and Efficient Electron Donor. Chemphyschem 2020; 21:725-740. [PMID: 32073190 DOI: 10.1002/cphc.202000117] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Indexed: 01/18/2023]
Abstract
We report herein the synthesis of aza-BODIPY substituted with strongly electron-donating p-(diphenylamino)phenyl substituents (p-Ph2 N-) at 3,5-positions. The presence of p-Ph2 N- groups lowers the energy of the singlet excited state (Es ) to 1.48 eV and induces NIR absorption with λabs at 789 nm in THF. The compound studied is weakly emissive with the emission band (λf ) at 837 nm and with the singlet lifetime (τS ) equal to 100 ps. Nanosecond laser photolysis experiments of the aza-BODIPY in question revealed T1 →Tn absorption spanning from ca. 350-550 nm with the triplet lifetime (τT ) equal to 21 μs. By introducing a heavy atom (Br) into the structure of the aza-BODIPY, we managed to turn it into a NIR operating photosensitizer. The photosensitized oxygenation of the model compound-diphenylisobenzofuran (DPBF)-proceedes via Type I and/or Type III mechanism without formation of singlet oxygen (1 O2 ). As estimated by CV/DPV measurements, the p-Ph2 N- substituted aza-BODIPYs studied exhibits oxidation processes at relatively low oxidation potentials (Eox 1 ), pointing to the very good electron-donating properties of these molecules. Extremely high photostability and thermal robustness up to approximately 300 °C are observed for the p-Ph2 N- substituted aza-BODIPYs.
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Affiliation(s)
- Łukasz Łapok
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387, Kraków, Poland
| | - Igor Cieślar
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387, Kraków, Poland
| | - Tomasz Pędziński
- Faculty of Chemistry, Adam Mickiewicz University in Poznań, 89b Umultowska, 61-614, Poznań, Poland.,Center for Advanced Technology, Adam Mickiewicz University in Poznań 10, 61-614, Poznań, Poland
| | - Katarzyna M Stadnicka
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387, Kraków, Poland
| | - Maria Nowakowska
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387, Kraków, Poland
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