1
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Zhao L, Jiang S, He Y, Wu L, James TD, Chen J. Excited-state dynamics of 4-hydroxyisoindoline-1,3-dione and its derivative as fluorescent probes. Phys Chem Chem Phys 2024; 26:13506-13514. [PMID: 38651980 DOI: 10.1039/d3cp05777a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Fluorescent probes have become promising tools for monitoring the concentration of peroxynitrite, which is linked to many diseases. However, despite focusing on developing numerous peroxynitrite based fluorescent probes, limited emphasis is placed on their sensing mechanism. Here, we investigated the sensing mechanism of a peroxynitrite fluorescent probe, named BHID-Bpin, with a focus on the relevant excited state dynamics. The photoexcited BHID-Bpin relaxes to its ground state via an efficient nonradiative process (∼300 ps) due to the presence of a minimum energy conical intersection between its first excited state and ground state. However, upon reacting with peroxynitrite, the Bpin moiety is cleaved from BHID-Bpin and BHID is formed. The formed BHID exhibits strong dual band fluorescence which is caused by an ultrafast excited-state intramolecular proton transfer process (∼1 ps).
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Affiliation(s)
- Li Zhao
- College of Science, China University of Petroleum (East China), Qingdao, 266580, Shandong, China
| | - Simin Jiang
- Nano-Science Center & Department of Chemistry University of Copenhagen, Universitetsparken 5, 2100 KøbenhavnØ, Denmark.
| | - Yanmei He
- Nano-Science Center & Department of Chemistry University of Copenhagen, Universitetsparken 5, 2100 KøbenhavnØ, Denmark.
- Department of Chemical Physics and NanoLund, Lund University, P. O. Box 124, 22100 Lund, Sweden
| | - Luling Wu
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK.
| | - Tony D James
- Department of Chemistry, University of Bath, Bath, BA2 7AY, UK.
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, China
| | - Junsheng Chen
- Nano-Science Center & Department of Chemistry University of Copenhagen, Universitetsparken 5, 2100 KøbenhavnØ, Denmark.
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2
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Bhattacharyya A, Das A, Guchhait N. Investigating the Photophysical Aspects of a Naphthalene-Based Excited-State Proton Transfer Dye 1-(1 H-Benzo[ d]imidazol-2-yl)naphthalen-2-ol: pH-Dependent Modulation of Photodynamics. J Phys Chem A 2024. [PMID: 38687998 DOI: 10.1021/acs.jpca.3c07420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
The steady state and time-resolved photophysical behavior of a proton transfer dye 1-(1H-benzo[d]imidazol-2-yl)naphthalen-2-ol (H-BINO) was investigated. The excited state intramolecular proton transfer (ESIPT) reaction in H-BINO is predominant in nonpolar solutions (toluene and DCM) with a lifetime of ∼1.0 ns. However, in polar media (DMF and MeOH), the excited state photodynamics is characterized by a complex equilibrium of emission from the locally excited state (0.1-2.3 ns), the phototautomer (0.5-1.2 ns), and the anionic emission (2.1-5.4 ns). In the solid state, emission from the various aggregated states dictates the photobehavior. Interestingly, the photodynamics in aqueous solution changes starkly as a function of pH with the anionic (2.1 ns) and phototautomeric (0.5-1.0 ns) emissions guiding the photodynamics as the pH of the medium increases. Optimized structural parameters at the proton donor and acceptor sites for the enol and keto forms and the calculated potential energy curve along the proton transfer coordinate at the density functional theory (DFT) level with the B3LYP/6-311G++(d,p) theory support a favorable and barrierless ESIPT process. The current results will surely boost the ongoing research on small molecule emissive materials.
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Affiliation(s)
| | - Akash Das
- Department of Chemistry, University of Calcutta, 92, A.P.C. Road, Kolkata 700009, India
| | - Nikhil Guchhait
- Department of Chemistry, University of Calcutta, 92, A.P.C. Road, Kolkata 700009, India
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3
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Bhattacharyya A, Das A, Guchhait N. Interrogating the nature of aggregates formed in a model azine based ESIPT coupled AIE active probe: stark differences in photodynamics in the solid state and aggregates in water. Phys Chem Chem Phys 2023; 25:31702-31713. [PMID: 37964573 DOI: 10.1039/d3cp03603k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
Abstract
A novel Schiff base 4-bromo-2-((E)-((E)-(1-(naphthalen-2-yl)ethylidene)hydrazono)methyl)phenol (BNHMP) was synthesized and characterized by NMR, ESI-MS, FTIR and single crystal X-ray diffraction studies. In the solution phase, BNHMP shows prominent emission from the keto-form, a consequence of excited state intramolecular proton transfer (ESIPT). The quantum yield and excited state lifetime decrease in polar solvent THF compared to relatively non-polar solvent DCM. Interestingly, in aqueous solution (pH 7.0), the quantum yield along with the excited state lifetime undergoes tremendous increment. Dynamic light scattering experiments and FESEM reveal the formation of aggregates in water as reflected by the increased hydrodynamic radius of BNHMP in water. Hence, aqueous phase studies revealed BNHMP to be an AIE active probe. On the other hand, BNHMP shows huge emission intensity in the solid state. Interestingly, the emission decay behavior of BNHMP changes upon excitation, as BNHMP shows very broad absorption in the solid state. Upon excitation at 360 nm, a triexponential decay pattern is found, which changes to a biexponential one upon excitation at 450 nm. Meticulous analysis of the fluorescence lifetimes led to the assignment of J and H aggregates coexisting in the solid state with the former dominating the photodynamics. A judicious comparison of the lifetime behavior in the solid state to that in water leads to the conclusion that BNHMP undergoes AIE by the formation of J and H aggregates to an equal extent, a phenomenon starkly different from the solid-state scenario. The current results hold significance as this is among a few reports where such comprehensive spectrodynamic dissection has been performed for an ESIPT-AIE active Schiff base in solution as well as in the solid phase, thereby giving a holistic vision of the nature and fate of aggregation occurring in such azine based systems and subsequently advancing the understanding of such systems in terms of their photo behavior.
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Affiliation(s)
| | - Akash Das
- Department of Chemistry, University of Calcutta, 92, A.P.C. Road, Kolkata, 700009, India.
| | - Nikhil Guchhait
- Department of Chemistry, University of Calcutta, 92, A.P.C. Road, Kolkata, 700009, India.
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Xie J, Wang Z, Zhu R, Jiang J, Weng TC, Ren Y, Han S, Huang Y, Liu W. Investigation of Excited-State Intramolecular Proton Transfer and Structural Dynamics in Bis-Benzimidazole Derivative (BBM). Int J Mol Sci 2023; 24:ijms24119438. [PMID: 37298391 DOI: 10.3390/ijms24119438] [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: 04/24/2023] [Revised: 05/19/2023] [Accepted: 05/24/2023] [Indexed: 06/12/2023] Open
Abstract
The bis-benzimidazole derivative (BBM) molecule, consisting of two 2-(2'-hydroxyphenyl) benzimidazole (HBI) halves, has been synthesized and successfully utilized as a ratiometric fluorescence sensor for the sensitive detection of Cu2+ based on enol-keto excited-state intramolecular proton transfer (ESIPT). In this study, we strategically implement femtosecond stimulated Raman spectroscopy and several time-resolved electronic spectroscopies, aided by quantum chemical calculations to investigate the detailed primary photodynamics of the BBM molecule. The results demonstrate that the ESIPT from BBM-enol* to BBM-keto* was observed in only one of the HBI halves with a time constant of 300 fs; after that, the rotation of the dihedral angle between the two HBI halves generated a planarized BBM-keto* isomer in 3 ps, leading to a dynamic redshift of BBM-keto* emission.
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Affiliation(s)
- Junhan Xie
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Ziyu Wang
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Ruixue Zhu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Jiaming Jiang
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Tsu-Chien Weng
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Yi Ren
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Shuhua Han
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, Shandong University, Jinan 250100, China
| | - Yifan Huang
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Weimin Liu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
- STU and SIOM Joint Laboratory for Superintense Lasers and the Applications, Shanghai 201210, China
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5
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Singhania A, Chatterjee S, Kalita S, Saha S, Chettri P, Gayen FR, Saha B, Sahoo P, Bandyopadhyay A, Ghosh S. An Inbuilt Electronic Pawl Gates Orbital Information Processing and Controls the Rotation of a Double Ratchet Rotary Motor. ACS APPLIED MATERIALS & INTERFACES 2023; 15:15595-15604. [PMID: 36926805 DOI: 10.1021/acsami.3c01103] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
A direct external input energy source (e.g., light, chemical reaction, redox potential, etc.) is compulsory to supply energy to rotary motors for accomplishing rotation around the axis. The stator leads the direction of rotation, and a sustainable rotation requires two mutual input energy supplies (e.g., light and heat, light and pH or metal ion, etc.); however, there are some exceptions (e.g., covalent single bond rotors and/or motors). On the contrary, our experiment suggested that double ratchet rotary motors (DRMs) can harvest power from available thermal noise, kT, for sustainable rotation around the axis. Under a scanning tunneling microscope, we have imaged live thermal noise movement as a dynamic orbital density and resolved the density diagram up to the second derivative. A second input energy can synchronize multiple rotors to afford a measurable output. Therefore, we hypothesized that rotation control in a DRM must be evolved from an orbital-level information transport channel between the two coupled rotors but was not limited to the second input energy. A DRM comprises a Brownian rotor and a power stroke rotor coupled to a -C≡C- stator, where the transport of information through coupled orbitals between the two rotors is termed the vibrational information flow chain (VIFC). We test this hypothesis by studying the DRM's density functional theory calculation and variable-temperature 1H nuclear magnetic resonance. Additionally, we introduced inbuilt pawl-like functional moieties into a DRM to create different electronic environments by changing proton intercalation interactions, which gated information processing through the VIFC. The results show the VIFC can critically impact the motor's noise harvesting, resulting in variable rotational motions in DRMs.
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Affiliation(s)
- Anup Singhania
- Natural Product Chemistry Group, Chemical Sciences & Technology Division, CSIR-North East Institute of Science & Technology, Jorhat 785006, Assam, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Satadru Chatterjee
- Natural Product Chemistry Group, Chemical Sciences & Technology Division, CSIR-North East Institute of Science & Technology, Jorhat 785006, Assam, India
| | - Sudeshna Kalita
- Natural Product Chemistry Group, Chemical Sciences & Technology Division, CSIR-North East Institute of Science & Technology, Jorhat 785006, Assam, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Supriya Saha
- Advanced Computation & Data Sciences Division, CSIR-North East Institute of Science & Technology, Jorhat 785006, Assam, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
- Green Engineered Materials and Additive Manufacturing Division, CSIR-AMPRI, 462026 Bhopal, Madhya Pradesh, India
| | - Prerna Chettri
- Natural Product Chemistry Group, Chemical Sciences & Technology Division, CSIR-North East Institute of Science & Technology, Jorhat 785006, Assam, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Firdaus Rahaman Gayen
- Advanced Materials Group, Material Sciences & Technology Division, CSIR-North East Institute of Science & Technology, Jorhat 785006, Assam, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Biswajit Saha
- Advanced Materials Group, Material Sciences & Technology Division, CSIR-North East Institute of Science & Technology, Jorhat 785006, Assam, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Pathik Sahoo
- International Center for Materials and Nanoarchitectronics (MANA) and Research Center for Advanced Measurement and Characterization (RCAMC), National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 3050047, Japan
| | - Anirban Bandyopadhyay
- International Center for Materials and Nanoarchitectronics (MANA) and Research Center for Advanced Measurement and Characterization (RCAMC), National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 3050047, Japan
| | - Subrata Ghosh
- Natural Product Chemistry Group, Chemical Sciences & Technology Division, CSIR-North East Institute of Science & Technology, Jorhat 785006, Assam, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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6
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de la Hoz Tomás M, Yamaguchi M, Cohen B, Hisaki I, Douhal A. Deciphering the ultrafast dynamics of a new tetraphenylethylene derivative in solutions: charge separation, phenyl ring rotation and CC bond twisting. Phys Chem Chem Phys 2023; 25:1755-1767. [PMID: 36594826 DOI: 10.1039/d2cp05220b] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Tetraphenylethylene (TPE) derivatives are one of the fundamental units for developing aggregation induced emission (AIE) scaffolds. However, the underlying mechanisms implicated in the relaxation of the excited TPE remain a topic of ongoing discussion, while the effect of bulky substituents on its photobehaviour is still under scrutiny. Here, we report a detailed study of the photophysical properties of a new symmetrical and bulky TPE derivative with terphenyl groups (TTECOOBu) in solvents of different polarities and viscosities. Using femto- to nanosecond (fs-ns) time-resolved absorption and emission techniques, we elucidated the role of the phenyl group rotations and core ethylene bond twisting in its behaviour. We demonstrate that TTECOOBu in DCM solutions undergoes a 600 fs charge separation along the ethylene bond leading to a resonance structure with a lifetime of ∼1 ns. The latter relaxes via two consecutive events: a twisting of the ethylene bond (∼ 9 ps) and a rotation of the phenyl rings (∼ 30 ps) leading to conformationally-relaxed species with a largely Stokes-shifted emission (∼ 12 500 cm-1). The formation of the red-emitting species clearly depends on the solvent viscosity and rigidity of the medium. Contrary to the photobehavior in the highly viscous triacetin or rigid polymer matrix of PMMA, a reversible mechanism was observed in DCM and DMF solutions. These results provide new findings on the ultrafast mechanisms of excited TPE derivatives and should help in the development of new molecular rotors with interesting AIE properties for photonic applications.
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Affiliation(s)
- Mario de la Hoz Tomás
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S/N, 45071 Toledo, Spain.
| | - Mao Yamaguchi
- Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan.
| | - Boiko Cohen
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S/N, 45071 Toledo, Spain.
| | - Ichiro Hisaki
- Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan.
| | - Abderrazzak Douhal
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S/N, 45071 Toledo, Spain.
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7
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Sánchez F, Gutiérrez M, Douhal A. Novel Approach for Detecting Vapors of Acids and Bases with Proton-Transfer Luminescent Dyes Encapsulated within Metal-Organic Frameworks. ACS APPLIED MATERIALS & INTERFACES 2022; 14:42656-42670. [PMID: 36067454 DOI: 10.1021/acsami.2c10573] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Luminescent metal-organic frameworks (LMOFs) are one of the most promising materials for being implemented as active layers in the fabrication of photonic devices such as luminescent sensors of harmful chemicals. It is highly desirable that these materials undergo quantifiable spectroscopic (absorption or emission) changes in the presence of vapors of those analytes, as in many industrial processes, these toxic compounds are in the gas phase. Although great progresses have been achieved in the field, in most of the examples reported hitherto, the detection of chemicals by LMOFs is attained in solution. Herein, we present a novel approach consisting of the encapsulation of proton transfer dyes (8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt, HPTS, and 3-hydroxyflavone, 3-HF) within the pores of two distinct MOFs. The trapped proton transfer dyes (PT-dyes) may exist as different structures (enol, anion, or zwitterion), each of these exhibiting unique optical properties. Indeed, our findings reveal that the dyes can be encapsulated as anionic or enol species. Remarkably, the PT-dye@MOF composites exhibit a high luminescence quantum yield (up to 30%), which is sensitive (showing shifting in the emission wavelengths with a concomitant quenching/enhancement of the intensity) in the presence of vapors of an acid (HCl) and a base (triethylamine). These results open a novel avenue for the development of smarter vapoluminescent MOF-based materials.
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Affiliation(s)
- Francisco Sánchez
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S/N, Toledo 45071, Spain
| | - Mario Gutiérrez
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S/N, Toledo 45071, Spain
| | - Abderrazzak Douhal
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S/N, Toledo 45071, Spain
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8
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Boulanger SA, Chen C, Myasnyanko IN, Baranov MS, Fang C. Fluorescence Modulation of ortho-Green Fluorescent Protein Chromophores Following Ultrafast Proton Transfer in Solution. J Phys Chem B 2022; 126:5081-5093. [PMID: 35786966 DOI: 10.1021/acs.jpcb.2c03812] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Photophysical and photochemical properties of the green fluorescent protein (GFP) chromophore and derivatives underlie their bioimaging applications. To date, ultrafast spectroscopic tools represent the key for unraveling fluorescence mechanisms toward rational design of this powerful biomimetic framework. To correlate the excited-state intramolecular proton transfer (ESIPT) with chromophore emission properties, we implement experimental and computational tool sets to elucidate real-time electronic and structural dynamics of two archetypal ortho-GFP chromophores (o-HBDI and o-LHBDI) possessing an intramolecular hydrogen bond to undergo efficient ESIPT, only differing in a bridge-bond constraint. Using excited-state femtosecond stimulated Raman spectroscopy (FSRS), a low-frequency phenolic (P)-ring-deformation mode (∼562 cm-1) was uncovered to accompany ESIPT. The tautomerized chromophore undergoes either rapid P-ring isomerization to reach the ground state with essentially no fluorescence for o-HBDI or enhanced (up to an impressive 180-fold in acetonitrile) and solvent-polarity-dependent fluorescence by P-ring locking in o-LHBDI. The significant dependence of the fluorescence enhancement ratio on solvent viscosity confirms P-ring isomerization as the dominant nonradiative decay pathway for o-HBDI. This work provides crucial insights into the dynamic solute-solvent electrostatic and steric interactions, enabling the application-specific improvement of ESIPT-capable molecules as versatile fluorescence-based sensors and imaging agents from large Stokes shift emission to brighter probes in physiological environments.
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Affiliation(s)
- Sean A Boulanger
- Department of Chemistry, Oregon State University, 153 Gilbert Hall, Corvallis, Oregon 97331, United States
| | - Cheng Chen
- Department of Chemistry, Oregon State University, 153 Gilbert Hall, Corvallis, Oregon 97331, United States
| | - Ivan N Myasnyanko
- Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, Moscow 117997, Russia.,Pirogov Russian National Research Medical University, Ostrovitianov 1, Moscow 117997, Russia
| | - Mikhail S Baranov
- Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, Moscow 117997, Russia.,Pirogov Russian National Research Medical University, Ostrovitianov 1, Moscow 117997, Russia
| | - Chong Fang
- Department of Chemistry, Oregon State University, 153 Gilbert Hall, Corvallis, Oregon 97331, United States
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9
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Gutiérrez M, García E, Monterde C, Sánchez F, Douhal A. Modulating the spectroscopy and dynamics of a proton-transfer dye by functionalizing with phenyl groups. Phys Chem Chem Phys 2022; 24:6828-6835. [PMID: 35244633 DOI: 10.1039/d1cp05294b] [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
Molecules undergoing excited-state proton transfer (ESPT) reactions are among the most interesting systems from spectroscopic and photophysical viewpoints. These molecules can be further functionalized with electron donating or accepting groups, inducing intramolecular charge transfer (ICT) events, which might be coupled to the ESIPT ones, conferring them with different spectroscopic and photophysical properties, which can be essential to implement the related materials in many key scientific and technological fields. Here, we report new benzimidazole derivatives that are functionalized with a phenyl group, 2-(5,10-diphenyl-1H-phenanthro[9,10-d]imidazol-2-yl)phenol (DP-HPPI), and its methylated equivalent, 2-(2-methoxyphenyl)-5,10-diphenyl-1H-phenanthro[9,10-d]imidazole (DP-MPPI). The results prove that these molecules in solutions undergo an ultrafast ICT (400-700 fs) reaction. Additionally, DP-HPPI also undergoes a reversible ESIPT process in dichloromethane. However, this is precluded in acetonitrile due to the involvement of intermolecular H-bonds in this solvent. These results provide key insights into the development of proton-transfer materials with bespoke spectral and photodynamical properties.
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Affiliation(s)
- Mario Gutiérrez
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S. N., 45071 Toledo, Spain.
| | - Eduardo García
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S. N., 45071 Toledo, Spain.
| | - Cristina Monterde
- Instituto de Química Orgánica General, IQOG-CSIC, Juan de la Cierva, 3, 28006 Madrid, Spain
| | - Félix Sánchez
- Instituto de Química Orgánica General, IQOG-CSIC, Juan de la Cierva, 3, 28006 Madrid, Spain
| | - Abderrazzak Douhal
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S. N., 45071 Toledo, Spain.
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10
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Li Y, Wang Y, Feng X, Zhao Y. Spectroscopic and mechanistic insights into solvent mediated excited-state proton transfer and aggregation-induced emission: introduction of methyl group onto 2-( o-hydroxyphenyl)benzoxazole. Phys Chem Chem Phys 2022; 24:26297-26306. [DOI: 10.1039/d2cp03007a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
2-(2-Hydroxy-5-methylphenyl)benzoxazole(HBO-pCH3), a solvatochromic benzoxazole-based probe, exhibited a typical dual fluorescence phenomenon, high fluorescence quantum yield, red-shifted emission and large Stokes’ shift via the ESIPT in solvents.
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Affiliation(s)
- Yu Li
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou, 310018, China
| | - Yuanyue Wang
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou, 310018, China
| | - Xiaoqing Feng
- School of Pharmacy & School of Medicine, Changzhou University, Changzhou 213164, China
| | - Yanying Zhao
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou, 310018, China
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11
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Joshi HC, Antonov L. Excited-State Intramolecular Proton Transfer: A Short Introductory Review. Molecules 2021; 26:molecules26051475. [PMID: 33803102 PMCID: PMC7963178 DOI: 10.3390/molecules26051475] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/03/2021] [Accepted: 03/04/2021] [Indexed: 12/03/2022] Open
Abstract
In this short review, we attempt to unfold various aspects of excited-state intramolecular proton transfer (ESIPT) from the studies that are available up to date. Since Weller’s discovery of ESIPT in salicylic acid (SA) and its derivative methyl salicylate (MS), numerous studies have emerged on the topic and it has become an attractive field of research because of its manifold applications. Here, we discuss some critical aspects of ESIPT and tautomerization from the mechanistic viewpoint. We address excitation wavelength dependence, anti-Kasha ESIPT, fast and slow ESIPT, reversibility and irreversibility of ESIPT, hydrogen bonding and geometrical factors, excited-state double proton transfer (ESDPT), concerted and stepwise ESDPT.
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Affiliation(s)
- Hem C. Joshi
- Institute for Plasma Research, Bhat, Gandhinagar 382428, India;
| | - Liudmil Antonov
- Institute of Electronics, Bulgarian Academy of Sciences, 1784 Sofia, Bulgaria
- Correspondence:
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12
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Ayare NN, Gupta PO, Sreenath MC, Chitrambalam S, Joe IH, Sekar N. NLOphoric imidazole-fused fluorescent anthraquinone dyes. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 246:119017. [PMID: 33045481 DOI: 10.1016/j.saa.2020.119017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 09/21/2020] [Accepted: 09/24/2020] [Indexed: 06/11/2023]
Abstract
The Z-scan and DFT techniques were explored to investigate the non-linear optical properties of anthraquinone fused imidazole-based D-π-A dyes. With the help of UV-visible spectral analysis, pH study, CV analysis, HOMO-LUMO interaction, MEP plots, and quinoidal character the influence of intramolecular charge transfer characteristics and H-bonding process on electronic and photophysical studies of anthraquinone derivatives were understood. The dyes 2-(4-(diethylamino)-2-hydroxyphenyl)-3H-anthra[1,2-d]imidazole-6,11-dione (AQ1) and 2-(2-hydroxynaphthalen-1-yl)-1H-anthra[1,2-d]imidazole-6,11-dione (AQ2) displayed a single emission with pronounced Stokes shift and thermal stability (upto 290 °C). The dye AQ1 exhibited strong charge transfer character which is explained by the ICT process leading to high nonlinear susceptibility χ(3) in AQ1 3.43 × 10-13 e.s.u relative to the dye AQ2 which has only ESIPT core. But, the dye AQ2 6.27 J cm-2 showed better optical limiting value. The NLO properties of AQ1 and AQ2 were computed by DFT functionals based on Hartree Fork (HF) percentage exchange. The dye AQ1 exhibits noticeable NLO properties. The global hybrid functionals with HF composition beyond 50% (BHHLYP, M06-HF) and the long rang corrected functionals (CAM-B3LYP, ωB97, and ωB97X) demonstrated comparable NLO properties relative to B3LYP and PBE0. It was observed that the combined effect of ICT and the H-bonding cores enhance the NLO properties. The experimental findings (Z-scan) were successfully correlated with theoretical (DFT) results.
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Affiliation(s)
- Nitesh N Ayare
- Dyestuff Technology Department, Institute of Chemical Technology, Nathalal Parekh Marg, Matunga, Mumbai 400019, India
| | - Puja O Gupta
- Dyestuff Technology Department, Institute of Chemical Technology, Nathalal Parekh Marg, Matunga, Mumbai 400019, India
| | - Mavila C Sreenath
- Centre for Molecular and Biophysics Research, Department of Physics, Mar Ivanios College, Thiruvananthapuram, Kerala 695015, India
| | - Subramaniyan Chitrambalam
- Centre for Molecular and Biophysics Research, Department of Physics, Mar Ivanios College, Thiruvananthapuram, Kerala 695015, India
| | - Isaac H Joe
- University of Kerala, Kariavattom, Trivandrum, 695581, Kerala, India
| | - Nagaiyan Sekar
- Dyestuff Technology Department, Institute of Chemical Technology, Nathalal Parekh Marg, Matunga, Mumbai 400019, India.
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13
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Korzec M, Malarz K, Mrozek-Wilczkiewicz A, Rzycka-Korzec R, Schab-Balcerzak E, Polański J. Live cell imaging by 3-imino-(2-phenol)-1,8-naphthalimides: The effect of ex vivo hydrolysis. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2020; 238:118442. [PMID: 32408229 DOI: 10.1016/j.saa.2020.118442] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 04/28/2020] [Accepted: 05/03/2020] [Indexed: 06/11/2023]
Abstract
A series of 3-amino-N-substituted-1,8-naphthalimides and their salicylic Schiff base derivatives were synthesized. The structure of the obtained compounds was confirmed using 1H and 13C NMR, FT-IR spectroscopy and elemental analysis and COSY and HMQC for the representative molecules. The photophysical (UV-Vis, PL) and biological properties of all of the prepared compounds were studied. It was found that the amine with the n-hexyl group in EtOH had the highest PL quantum yield (Ф = 85%) compared to the others. Moreover, the chelating properties of the azomethines with the n-hexyl group (1a, 1b, 1c) were tested against various cations (Al3+, Ba2+, Co2+, Cu2+, Cr3+, Fe2+, Fe3+, Mn2+, Ni2+, Pb2+, Sr2+ and Zn2+) in an acetonitrile, acetone and PBS/AC mixture. Compounds that contained the electron withdrawing groups (-Br, -I) had the ability to chelate most of the studied cations, while the unsubstituted derivative chelated only the trivalent cations such as Al3+, Cr3+ and Fe3+ in acetonitrile. The effect of the environment on the keto-enol tautomeric equilibrium was also demonstrated, especially in the case of the derivative with a bromine atom. The biological studies showed that the tested molecules had no cytotoxicity. Additionally, the ability to image intracellular organelles such as the mitochondria and endoplasmic reticulum was revealed. The crucial role of the hydrolysis of imines for cellular imaging was presented.
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Affiliation(s)
- Mateusz Korzec
- Institute of Chemistry, University of Silesia in Katowice, 9 Szkolna Str., 40-006 Katowice, Poland.
| | - Katarzyna Malarz
- A. Chelkowski Institute of Physics, University of Silesia in Katowice, 75 Pułku Piechoty 1, 41-500 Chorzow, Poland; Silesian Center for Education and Interdisciplinary Research, University of Silesia in Katowice, 75 Pułku Piechoty 1A, 41-500 Chorzow, Poland
| | - Anna Mrozek-Wilczkiewicz
- A. Chelkowski Institute of Physics, University of Silesia in Katowice, 75 Pułku Piechoty 1, 41-500 Chorzow, Poland; Silesian Center for Education and Interdisciplinary Research, University of Silesia in Katowice, 75 Pułku Piechoty 1A, 41-500 Chorzow, Poland
| | - Roksana Rzycka-Korzec
- Institute of Chemistry, University of Silesia in Katowice, 9 Szkolna Str., 40-006 Katowice, Poland; Silesian Center for Education and Interdisciplinary Research, University of Silesia in Katowice, 75 Pułku Piechoty 1A, 41-500 Chorzow, Poland
| | - Ewa Schab-Balcerzak
- Institute of Chemistry, University of Silesia in Katowice, 9 Szkolna Str., 40-006 Katowice, Poland
| | - Jarosław Polański
- Institute of Chemistry, University of Silesia in Katowice, 9 Szkolna Str., 40-006 Katowice, Poland; Silesian Center for Education and Interdisciplinary Research, University of Silesia in Katowice, 75 Pułku Piechoty 1A, 41-500 Chorzow, Poland
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14
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Ni M, Fang H. Modulating excited‐state intramolecular proton transfer of 2‐(5‐(4‐carboxyphenyl)‐2‐hydroxyphenyl)benzothiazole depending on substituents: A DFT/TD‐DFT study. J PHYS ORG CHEM 2020. [DOI: 10.1002/poc.4109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Mei Ni
- Department of Chemistry and Material Science, College of Science Nanjing Forestry University Nanjing China
| | - Hua Fang
- Department of Chemistry and Material Science, College of Science Nanjing Forestry University Nanjing China
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15
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Femto- to Millisecond Time-Resolved Photodynamics of a Double-Functionalized Push-Pull Organic Linker: Potential Candidate for Optoelectronically Active MOFs. Int J Mol Sci 2020; 21:ijms21124366. [PMID: 32575438 PMCID: PMC7352538 DOI: 10.3390/ijms21124366] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/11/2020] [Accepted: 06/16/2020] [Indexed: 12/25/2022] Open
Abstract
The design of improved organic linkers for the further engineering of smarter metal–organic framework (MOF) materials has become a paramount task for a wide number of material scientists. In this report, a luminescent double-functionalized push–pull (electron donor–acceptor) archetype organic molecule, dimethyl 4-amino-8-cyanonaphthalene-2,6-dicarboxylate (Me2CANADC), has been synthesized and characterized. The optical steady-state properties of Me2CANADC are strongly influenced by the surrounding environment as a direct consequence of its strong charge transfer (CT) character. The relaxation from its first electronically excited singlet state follows a double pathway: (1) on one side deactivating from its local excited (LE) state in the sub-picosecond or picosecond time domain, and (2) on the other side undergoing an ultrafast intramolecular charge transfer (ICT) reaction that is slowing down in viscous solvents. The deactivation to the ground state of these species with CT character is the origin of the Me2CANADC luminescence, and they present solvent-dependent lifetime values ranging from 8 to 18 ns. The slow photodynamics of Me2CANADC unveils the coexistence of a non-emissive triplet excited state and the formation of a long-lived charge separated state (2 µs). These observations highlight the promising optical properties of Me2CANADC linker, opening a window for the design of new functional MOFs with huge potential to be applied in the fields of luminescent sensing and optoelectronics.
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16
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Ni M, Su S, Fang H. Substituent control of photophysical properties for excited-state intramolecular proton transfer (ESIPT) of o-LHBDI derivatives: a TD-DFT investigation. J Mol Model 2020; 26:108. [PMID: 32328800 DOI: 10.1007/s00894-020-04378-5] [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: 02/04/2020] [Accepted: 04/07/2020] [Indexed: 11/24/2022]
Abstract
The substituted effect on excited-state intramolecular proton transfer (ESIPT) of o-LHBDI derivatives (4R-o-LHBDI) was investigated by DFT and TD-DFT methods. The structures of 4R-o-LHBDI (R: OH, NH2, CN, NO2, CF3) were fully optimized, and the H-bond distances, bond angles, and infrared spectra of the atoms involved in PT process in the S0 and S1 states were analyzed. The absorption and fluorescence spectra were calculated, and the potential energy curves in both S0 and S1 states were constructed. Moreover, the effects of different substituents on the ESIPT mechanism of 4R-o-LHBDI (R: OH, NH2, CN, NO2, CF3) were studied. The results indicate that ESIPT in the 4R-o-LHBDI is a little harder to proceed than that in o-LHBDI since the ESIPT barrier of 4R-o-LHBDI is slightly bigger than that value of o-LHBDI. When the substituent has stronger electron-withdrawing ability or weaker electron-donating ability, the ESIPT process has the smaller potential barrier. Graphical abstract.
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Affiliation(s)
- Mei Ni
- Department of Chemistry and Material Science, College of Science, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
| | - Shenyang Su
- Department of Chemistry and Material Science, College of Science, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
| | - Hua Fang
- Department of Chemistry and Material Science, College of Science, Nanjing Forestry University, Nanjing, 210037, People's Republic of China.
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17
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Angiolini L, Cohen B, Douhal A. Ultrafast dynamics of the antibiotic Rifampicin in solution. Photochem Photobiol Sci 2019; 18:80-91. [DOI: 10.1039/c8pp00192h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ultrafast time-resolved studies demonstrate that intra- and intermolecular H-bonds with water molecules act synergistically to stabilize the active zwitterionic form of Rifampicin, an effective antibiotic against mycobacterial infections.
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Affiliation(s)
- Lorenzo Angiolini
- Departamento de Química Física
- Facultad de Ciencias Ambientales y Bioquímica and INAMOL
- Universidad de Castilla-La Mancha
- 45071 Toledo
- Spain
| | - Boiko Cohen
- Departamento de Química Física
- Facultad de Ciencias Ambientales y Bioquímica and INAMOL
- Universidad de Castilla-La Mancha
- 45071 Toledo
- Spain
| | - Abderrazzak Douhal
- Departamento de Química Física
- Facultad de Ciencias Ambientales y Bioquímica and INAMOL
- Universidad de Castilla-La Mancha
- 45071 Toledo
- Spain
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18
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Wiethaus G, Toldo JM, da Silveira Santos F, da Costa Duarte R, Gonçalves PFB, Rodembusch FS. Experimental and theoretical investigation of long-wavelength fluorescence emission in push–pull benzazoles: intramolecular proton transfer or charge transfer in the excited state? Phys Chem Chem Phys 2019; 21:4408-4420. [DOI: 10.1039/c8cp05186k] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
ESIPT is disfavoured and charge-transfer emission, prior to ESIPT, seems to be responsible for long-emission wavelengths.
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Affiliation(s)
- Guilherme Wiethaus
- Grupo de Pesquisa em Fotoquímica Orgânica Aplicada
- Universidade Federal do Rio Grande do Sul – Instituto de Química
- Porto Alegre-RS
- Brazil
| | - Josene Maria Toldo
- Grupo de Química Teórica e Computacional
- Universidade Federal do Rio Grande do Sul – Instituto de Química
- Porto Alegre-RS
- Brazil
| | - Fabiano da Silveira Santos
- Grupo de Pesquisa em Fotoquímica Orgânica Aplicada
- Universidade Federal do Rio Grande do Sul – Instituto de Química
- Porto Alegre-RS
- Brazil
| | - Rodrigo da Costa Duarte
- Grupo de Pesquisa em Fotoquímica Orgânica Aplicada
- Universidade Federal do Rio Grande do Sul – Instituto de Química
- Porto Alegre-RS
- Brazil
| | - Paulo Fernando Bruno Gonçalves
- Grupo de Química Teórica e Computacional
- Universidade Federal do Rio Grande do Sul – Instituto de Química
- Porto Alegre-RS
- Brazil
| | - Fabiano Severo Rodembusch
- Grupo de Pesquisa em Fotoquímica Orgânica Aplicada
- Universidade Federal do Rio Grande do Sul – Instituto de Química
- Porto Alegre-RS
- Brazil
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19
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Kroetz T, dos Santos MC, Beal R, Zanotto GM, Santos FS, Giacomelli FC, Gonçalves PFB, de Lima VR, Dal-Bó AG, Rodembusch FS. Proton transfer in fluorescent secondary amines: synthesis, photophysics, theoretical calculation and preparation of photoactive phosphatidylcholine-based liposomes. Photochem Photobiol Sci 2019; 18:1171-1184. [DOI: 10.1039/c9pp00017h] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
New proton-transfer lipophilic based benzazoles.
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Affiliation(s)
- Thais Kroetz
- Grupo de Pesquisa em Fotoquímica Orgânica Aplicada
- Universidade Federal do Rio Grande do Sul – Instituto de Química
- CEP 91501-970 Porto Alegre-RS
- Brazil
| | | | - Roiney Beal
- Grupo de Química Teórica
- Instituto de Química
- Universidade Federal do Rio Grande do Sul
- Porto Alegre-RS
- Brazil
| | - Gabriel Modernell Zanotto
- Grupo de Química Teórica
- Instituto de Química
- Universidade Federal do Rio Grande do Sul
- Porto Alegre-RS
- Brazil
| | | | | | - Paulo F. B. Gonçalves
- Grupo de Química Teórica
- Instituto de Química
- Universidade Federal do Rio Grande do Sul
- Porto Alegre-RS
- Brazil
| | | | | | - Fabiano S. Rodembusch
- Grupo de Pesquisa em Fotoquímica Orgânica Aplicada
- Universidade Federal do Rio Grande do Sul – Instituto de Química
- CEP 91501-970 Porto Alegre-RS
- Brazil
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20
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Li C, Guo W, Zhou P, Tang Z. The effects of the heteroatom and position on excited-state intramolecular proton transfer of new hydroxyphenyl benzoxazole derivatives: a time-dependent density functional theory study. Org Chem Front 2019. [DOI: 10.1039/c9qo00295b] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The effects of the heteroatom and position on excited-state intramolecular proton transfer (ESIPT) of 2-[4′-(N-4,6-dichloro-1,3,5-triazi-n-2-yl)2′hydroxyphenyl]benzoxazole (4THBO) have been investigated via time-dependent density functional theory studies.
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Affiliation(s)
- Changming Li
- School of Electrical Engineering
- University of South China
- Hengyang 421001
- China
- State Key Lab of Molecular Reaction Dynamics
| | - Wei Guo
- School of Electrical Engineering
- University of South China
- Hengyang 421001
- China
| | - Panwang Zhou
- Institute of Molecular Sciences and Engineering
- Shandong University
- Qingdao 266235
- P. R. China
| | - Zhe Tang
- Institute of Molecular Sciences and Engineering
- Shandong University
- Qingdao 266235
- P. R. China
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21
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Gomez E, Alarcos N, Monterde C, Sánchez F, Moreno M, Douhal A. Experimental and theoretical insights into the influence of electronic density on proton-transfer reactions. Phys Chem Chem Phys 2018; 20:27149-27161. [PMID: 30334550 DOI: 10.1039/c8cp03185a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report on the excited-state behavior of proton-transfer phenanthroimidazole derivatives, such as HPPI and NMHPPI, in solutions using steady-state and femto- to nanosecond time-resolved fluorescence spectroscopies. Experimental observations are supported by theoretical calculations (TDDFT). In dichloromethane (DCM) and acetonitrile (ACN), two different paths are found for the excited-state intramolecular proton-transfer (ESIPT) reactions following two different channels. A fast and direct channel (ESIPT1) in 1-2.5 ps and a slower one (ESIPT2) in 12-15 ps, the latter being more influenced by the solvent viscosity (30 ps for HPPI and 20 ps for NMHPPI in triacetin (TAC) solutions). The slowing down of the ESIPT2 reaction is explained in terms of an intramolecular charge transfer (ICT) reaction coupled to a twisting motion to reach a more suitable conformation of the involved parts in the proton-transfer motion. The absence of OH/OD exchange effects in the ultrafast and slow proton-transfer dynamics suggests that the ESIPT reactions, which involve intramolecular and solvent coordinates, do not occur via tunneling. These results reveal new insights into the photobehavior of proton-transfer dyes, which might help in designing photosensors or lighting devices.
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Affiliation(s)
- Eduardo Gomez
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S.N., 45071 Toledo, Spain.
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22
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Du C, Zhou Q, Zhang M, Song P, Ma F. Excited-state intramolecular proton transfer of 6-amino-2-(2′-hydroxyphenyl) benzoxazole (6A-HBO) in different solvents. J PHYS ORG CHEM 2018. [DOI: 10.1002/poc.3901] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Can Du
- Department of Physics; Liaoning University; Shenyang China
| | - Qiao Zhou
- Department of Physics; Liaoning University; Shenyang China
| | - Meixia Zhang
- Department of Physics; Liaoning University; Shenyang China
| | - Peng Song
- Department of Physics; Liaoning University; Shenyang China
- Liaoning Key Laboratory of Semiconductor Light Emitting and Photocatalytic Materials; Liaoning University; Shenyang China
| | - Fengcai Ma
- Department of Physics; Liaoning University; Shenyang China
- Liaoning Key Laboratory of Semiconductor Light Emitting and Photocatalytic Materials; Liaoning University; Shenyang China
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23
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24
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Yang D, Yang G, Jia M, Song X, Zhang Q. Comparing the substituent effects about ESIPT process for HBO derivatives. COMPUT THEOR CHEM 2018. [DOI: 10.1016/j.comptc.2018.03.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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25
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Mukherjee P, Das A, Faizi MSH, Sen P. Solvent Relaxation Accompanied Ultrafast Excited State Proton Transfer Dynamics Revealed in a Salicylideneaniline Derivative. ChemistrySelect 2018. [DOI: 10.1002/slct.201800380] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Puspal Mukherjee
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur - 208 016 India
| | - Aritra Das
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur - 208 016 India
| | - Md. Serajul Haque Faizi
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur - 208 016 India
- Present address: Department of Chemistry, Langat Singh College; B. R. A. Bihar University, Muzaffarpur; Bihar - 842001 India
| | - Pratik Sen
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur - 208 016 India
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26
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Tong Y, Mei W, Ma J. Theoretical insight into the excited-state proton transfer process: Role of the substituent -CN on HBT system. J PHYS ORG CHEM 2018. [DOI: 10.1002/poc.3832] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Yuping Tong
- School of Civil Engineering and Communication; North China University of Water Resources and Electric Power; Zhengzhou China
| | - Wanwan Mei
- School of Civil Engineering and Communication; North China University of Water Resources and Electric Power; Zhengzhou China
| | - Juntao Ma
- School of Civil Engineering and Communication; North China University of Water Resources and Electric Power; Zhengzhou China
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27
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Mohbiya DR, Sekar N. Tuning ‘Stokes Shift’ and ICT Character by Varying the Donor Group in Imidazo[1,5 a]pyridines: A Combined Optical, DFT, TD-DFT and NLO Approach. ChemistrySelect 2018. [DOI: 10.1002/slct.201702579] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Dhanraj R. Mohbiya
- Dyestuff Technology Department; Institute of Chemical Technology; Nathalal Parekh Marg, Matunga Mumbai 400019 India
| | - Nagaiyan Sekar
- Dyestuff Technology Department; Institute of Chemical Technology; Nathalal Parekh Marg, Matunga Mumbai 400019 India
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28
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Li B, Zhou L, Cheng H, Huang Q, Lan J, Zhou L, You J. Dual-emissive 2-(2'-hydroxyphenyl)oxazoles for high performance organic electroluminescent devices: discovery of a new equilibrium of excited state intramolecular proton transfer with a reverse intersystem crossing process. Chem Sci 2017; 9:1213-1220. [PMID: 29675166 PMCID: PMC5885805 DOI: 10.1039/c7sc04464j] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 11/30/2017] [Indexed: 12/24/2022] Open
Abstract
Dual-emission of the enol-forms and keto-forms of 2-(2′-hydroxyphenyl)oxazoles and their application in OLEDs are investigated.
The photoluminescence (PL) and electroluminescence (EL) properties of two highly efficient excited state intramolecular proton transfer (ESIPT) molecules, 2-(2′-hydroxyphenyl)oxazoles containing one triphenylamine (TPA) (1) and two TPAs (2) respectively, are studied systematically. The enol-forms of both 1 and 2 possess highly hybridized local and charge transfer (HLCT) excited state character, while their excited-state keto-forms are not of obvious HLCT character. A 1-based device exhibits green-white electroluminescence with Commission Internationale d’Eclairage (CIE) coordinates of (0.25, 0.41) and a high external quantum efficiency (EQE) up to 5.3%, which is the highest EQE value recorded for single molecular white light-emitting materials. A 2-based device shows sky-blue emission with CIE coordinates of (0.18, 0.16) and an EQE of 8.0%, which is the highest EQE in the reported HLCT materials. The fluorescence intensities of the enol-forms of 1 and 2 in EL spectra are increased remarkably relative to their PL spectra. Experimental data and theoretical calculations reveal a new ESIPT equilibrium with a reverse intersystem crossing (RISC) process arising from the HLCT character. In EL, the RISC of the enol-form excitons from the triplet state to the singlet state triggers an increase in the number of enol-form singlet excitons, which further leads to a shift of the ESIPT equilibrium towards an enhanced enol-form emission. Thus, the difference between the ESIPT equilibria in PL and EL may be ascribed to the HLCT character of the enol-form excited state.
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Affiliation(s)
- Bijin Li
- Key Laboratory of Green Chemistry and Technology of Ministry of Education , College of Chemistry , Sichuan University , 29 Wangjiang Road , Chengdu 610064 , PR China . ;
| | - Linsen Zhou
- Center of Interface Dynamics for Sustainability , Institute of Materials , China Academy of Engineering Physics , 596 Yinhe Road , Chengdu 610200 , PR China
| | - Hu Cheng
- Key Laboratory of Green Chemistry and Technology of Ministry of Education , College of Chemistry , Sichuan University , 29 Wangjiang Road , Chengdu 610064 , PR China . ;
| | - Quan Huang
- Key Laboratory of Green Chemistry and Technology of Ministry of Education , College of Chemistry , Sichuan University , 29 Wangjiang Road , Chengdu 610064 , PR China . ;
| | - Jingbo Lan
- Key Laboratory of Green Chemistry and Technology of Ministry of Education , College of Chemistry , Sichuan University , 29 Wangjiang Road , Chengdu 610064 , PR China . ;
| | - Liang Zhou
- State Key Laboratory of Rare Earth Resource Utilization , Changchun Institute of Applied Chemistry , Chinese Academy of Sciences , 5625 Renmin Street , Changchun 130022 , PR China .
| | - Jingsong You
- Key Laboratory of Green Chemistry and Technology of Ministry of Education , College of Chemistry , Sichuan University , 29 Wangjiang Road , Chengdu 610064 , PR China . ;
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29
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Alarcos N, Cohen B, Ziółek M, Douhal A. Photochemistry and Photophysics in Silica-Based Materials: Ultrafast and Single Molecule Spectroscopy Observation. Chem Rev 2017; 117:13639-13720. [PMID: 29068670 DOI: 10.1021/acs.chemrev.7b00422] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Silica-based materials (SBMs) are widely used in catalysis, photonics, and drug delivery. Their pores and cavities act as hosts of diverse guests ranging from classical dyes to drugs and quantum dots, allowing changes in the photochemical behavior of the confined guests. The heterogeneity of the guest populations as well as the confinement provided by these hosts affect the behavior of the formed hybrid materials. As a consequence, the observed reaction dynamics becomes significantly different and complex. Studying their photobehavior requires advanced laser-based spectroscopy and microscopy techniques as well as computational methods. Thanks to the development of ultrafast (spectroscopy and imaging) tools, we are witnessing an increasing interest of the scientific community to explore the intimate photobehavior of these composites. Here, we review the recent theoretical and ultrafast experimental studies of their photodynamics and discuss the results in comparison to those in homogeneous media. The discussion of the confined dynamics includes solvation and intra- and intermolecular proton-, electron-, and energy transfer events of the guest within the SBMs. Several examples of applications in photocatalysis, (photo)sensors, photonics, photovoltaics, and drug delivery demonstrate the vast potential of the SBMs in modern science and technology.
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Affiliation(s)
- Noemí Alarcos
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha , Avenida Carlos III, S.N., 45071 Toledo, Spain
| | - Boiko Cohen
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha , Avenida Carlos III, S.N., 45071 Toledo, Spain
| | - Marcin Ziółek
- Quantum Electronics Laboratory, Faculty of Physics, Adam Mickiewicz University , Umultowska 85, 61-614 Poznań, Poland
| | - Abderrazzak Douhal
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha , Avenida Carlos III, S.N., 45071 Toledo, Spain
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Li Y, Chu TS. DFT/TDDFT Study on the Sensing Mechanism of a Fluorescent Probe for Hydrogen Sulfide: Excited State Intramolecular Proton Transfer Coupled Twisted Intramolecular Charge Transfer. J Phys Chem A 2017. [DOI: 10.1021/acs.jpca.7b02606] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Yang Li
- State Key Laboratory
of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Tian-Shu Chu
- State Key Laboratory
of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- Institute for Computational Sciences and
Engineering, Laboratory of New Fiber Material and Modern Textile,
the Growing Base for State Key Laboratory, Qingdao University, Qingdao 266071, P. R. China
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31
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Substituent Modulation from ESIPT to ICT Emission in Benzoimidazolphenyl-methanones Derivatives: Synthesis, Photophysical and DFT Study. J SOLUTION CHEM 2017. [DOI: 10.1007/s10953-017-0602-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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32
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Kumpulainen T, Lang B, Rosspeintner A, Vauthey E. Ultrafast Elementary Photochemical Processes of Organic Molecules in Liquid Solution. Chem Rev 2016; 117:10826-10939. [DOI: 10.1021/acs.chemrev.6b00491] [Citation(s) in RCA: 249] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Tatu Kumpulainen
- Department of Physical Chemistry,
Sciences II, University of Geneva, 30 Quai Ernest Ansermet, CH-1211 Geneva 4, Switzerland
| | - Bernhard Lang
- Department of Physical Chemistry,
Sciences II, University of Geneva, 30 Quai Ernest Ansermet, CH-1211 Geneva 4, Switzerland
| | - Arnulf Rosspeintner
- Department of Physical Chemistry,
Sciences II, University of Geneva, 30 Quai Ernest Ansermet, CH-1211 Geneva 4, Switzerland
| | - Eric Vauthey
- Department of Physical Chemistry,
Sciences II, University of Geneva, 30 Quai Ernest Ansermet, CH-1211 Geneva 4, Switzerland
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Gutiérrez M, Sánchez F, Douhal A. Competitive Excimer Formation and Energy Transfer in Zr-Based Heterolinker Metal-Organic Frameworks. Chemistry 2016; 22:13072-82. [DOI: 10.1002/chem.201600669] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Mario Gutiérrez
- Departamento de Química Física; Facultad de Ciencias Ambientales y Bioquímica and INAMOL; Universidad de Castilla-La Mancha; Avenida Carlos III, S.N. 45071 Toledo Spain
| | - Félix Sánchez
- Instituto de Química Orgánica; Consejo Superior de Investigaciones Cientificas (CSIC); C/Juan de la Cierva, 3 28006 Madrid Spain
| | - Abderrazzak Douhal
- Departamento de Química Física; Facultad de Ciencias Ambientales y Bioquímica and INAMOL; Universidad de Castilla-La Mancha; Avenida Carlos III, S.N. 45071 Toledo Spain
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Clementi C, Cesaretti A, Carlotti B, Elisei F. The Role of pH in Modulating the Electronic State Properties of Minocycline Drug and Its Inclusion within Micellar Carriers. J Phys Chem A 2016; 120:4994-5005. [DOI: 10.1021/acs.jpca.5b12707] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Catia Clementi
- Department
of Chemistry,
Biology and Biotechnology and Center of Excellence on the Innovative
Nanostructured Materials (CEMIN), University of Perugia, via Elce
di Sotto 8, 06123 Perugia, Italy
| | - Alessio Cesaretti
- Department
of Chemistry,
Biology and Biotechnology and Center of Excellence on the Innovative
Nanostructured Materials (CEMIN), University of Perugia, via Elce
di Sotto 8, 06123 Perugia, Italy
| | - Benedetta Carlotti
- Department
of Chemistry,
Biology and Biotechnology and Center of Excellence on the Innovative
Nanostructured Materials (CEMIN), University of Perugia, via Elce
di Sotto 8, 06123 Perugia, Italy
| | - Fausto Elisei
- Department
of Chemistry,
Biology and Biotechnology and Center of Excellence on the Innovative
Nanostructured Materials (CEMIN), University of Perugia, via Elce
di Sotto 8, 06123 Perugia, Italy
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Azarias C, Budzák Š, Laurent AD, Ulrich G, Jacquemin D. Tuning ESIPT fluorophores into dual emitters. Chem Sci 2016; 7:3763-3774. [PMID: 29997864 PMCID: PMC6008603 DOI: 10.1039/c5sc04826e] [Citation(s) in RCA: 124] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 02/23/2016] [Indexed: 12/24/2022] Open
Abstract
Using first-principle approaches, we show how ESIPT can be controlled by fine-tuning of substituents, hence leading to new dual emitters.
Dyes undergoing excited-state intramolecular proton transfer (ESIPT) are known to present large Stokes shifts as a result of the important geometrical reorganisation following photon absorption. When the ESIPT process is not quantitative, one can obtain dual emitters characterised by two distinct fluorescence bands, observed due to emissions from both the canonical and ESIPT isomers. However, dual emission generally requires to maintain a very specific balance, as the relative excited-state free energies of the two tautomers have to be within a narrow window to observe the phenomenon. Consequently, simple chemical intuition is insufficient to optimise dual emission. In the present contribution, we investigate, with the help of quantum-mechanical tools and more precisely, time-dependent density functional theory (TD-DFT) and algebraic diagrammatic construction (ADC), a wide panel of possible ESIPT/dual emitters with various substituents. The selected protocol is first shown to be very robust on a series of structures with known experimental behaviour, and next is applied to novel derivatives with various substituents located at different positions. This work encompasses the largest chemical library of potential ESIPT compounds studied to date. We pinpoint the most promising combinations for building dual emitters, highlight unexpected combination effects and rationalise the impact of the different auxochromes.
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Affiliation(s)
- Cloé Azarias
- CEISAM , UMR CNRS 6230 , Université de Nantes , BP 92208, 2, Rue de la Houssinière , 44322 Nantes, Cedex 3 , France . ; Tel: +33-2-51-12-55-64
| | - Šimon Budzák
- CEISAM , UMR CNRS 6230 , Université de Nantes , BP 92208, 2, Rue de la Houssinière , 44322 Nantes, Cedex 3 , France . ; Tel: +33-2-51-12-55-64
| | - Adèle D Laurent
- CEISAM , UMR CNRS 6230 , Université de Nantes , BP 92208, 2, Rue de la Houssinière , 44322 Nantes, Cedex 3 , France . ; Tel: +33-2-51-12-55-64
| | - Gilles Ulrich
- Institut de Chimie et Procédés pour l'Energie , l'Environnement et la Santé (ICPEES) UMR7515 CNRS Université de Strasbourg , 25 rue Becquerel , 67087 Strasbourg Cedex 02 , France
| | - Denis Jacquemin
- CEISAM , UMR CNRS 6230 , Université de Nantes , BP 92208, 2, Rue de la Houssinière , 44322 Nantes, Cedex 3 , France . ; Tel: +33-2-51-12-55-64.,Institut Universitaire de France , 1, rue Descartes , F-75005 Paris Cedex 05 , France
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Alarcos N, Gutiérrez M, Liras M, Sánchez F, Moreno M, Douhal A. Direct observation of breaking of the intramolecular H-bond, and slowing down of the proton motion and tuning its mechanism in an HBO derivative. Phys Chem Chem Phys 2016; 17:14569-81. [PMID: 25966780 DOI: 10.1039/c5cp01437a] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
We report on spectroscopic and photodynamical behaviours of 5-amino-2-(2'-hydroxyphenyl)benzoxazole (5A-HBO) in different solutions. The dye undergoes an ultrafast ICT reaction (<50 fs) (comparable to that observed for its methylated derivative, 5A-MBO), in agreement with the results of TD-DFT theoretical calculations (gas phase). Depending on the used solvent, the ICT reaction can be followed by a reversible/irreversible excited-state intramolecular proton transfer (ESIPT) reaction or by breaking of the intramolecular hydrogen bond (IHB). 5A-HBO in n-heptane solution exhibits an irreversible and slow (20 ps) ESIPT reaction, while that of the parent compound, HBO, takes place in less than 150 fs. Compared to excited HBO behaviour, theoretical calculations on 5A-HBO suggest a higher energy barrier (∼4 kcal mol(-1)) between the relaxed enol and keto tautomers, in addition to a less stabilization of the latter, which is in agreement with experiments in n-heptane. On the other hand, in dichloromethane, after the ICT reaction a subsequent and reversible proton motion occurs in an extraordinary slower regime (ns-time scale). No isotopic effect (OH/OD exchange) was observed in this solvent reflecting that the reversible ESIPT reaction evolves along the IHB and solvent coordinates. Using tetrahydrofurane and acetonitrile, we observed a breaking of the IHB due to specific intermolecular interactions with solvent molecules. This leads to the formation of open-enol forms, which undergo an ICT reaction as it occurs in 5A-MBO. These results bring new findings in the coupled ICT and ESIPT reactions. The photobehaviour of this new dye remarkably changes with the solvent nature, opening up the window for further research and possible applications in sensing polarity or H-bonding of media similar to that of the biological ones.
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Affiliation(s)
- Noemí Alarcos
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S.N., 45071 Toledo, Spain.
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37
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Li C, Yang Y, Ma C, Liu Y. Effect of amino group on the excited-state intramolecular proton transfer (ESIPT) mechanisms of 2-(2′-hydroxyphenyl)benzoxazole and its amino derivatives. RSC Adv 2016. [DOI: 10.1039/c5ra23261a] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The electronic density redistributes and it migrates in opposite directions for HBO when compared to those of 5A-HBO and 6A-HBO. The amino group in the HBO framework can change the behavior of the intramolecular hydrogen bonds.
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Affiliation(s)
- Chaozheng Li
- College of Physics and Electronic Engineer
- Henan Normal University
- Xinxiang 453007
- China
| | - Yonggang Yang
- College of Physics and Electronic Engineer
- Henan Normal University
- Xinxiang 453007
- China
| | - Chi Ma
- College of Physics and Electronic Engineer
- Henan Normal University
- Xinxiang 453007
- China
| | - Yufang Liu
- College of Physics and Electronic Engineer
- Henan Normal University
- Xinxiang 453007
- China
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Alarcos N, Gutiérrez M, Liras M, Sánchez F, Douhal A. From intra- to inter-molecular hydrogen bonds with the surroundings: steady-state and time-resolved behaviours. Photochem Photobiol Sci 2015; 14:1306-18. [PMID: 26066612 DOI: 10.1039/c5pp00079c] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report on the photodynamics of 2-(2'-hydroxyphenyl)benzoxazole (HBO), compared to its amino derivatives, 6-amino-2-(2'-hydroxypheny)benzoxazole (6A-HBO) and 5-amino-2-(2'-hydroxypheny)benzoxazole (5A-HBO) in N,N-dimethylformamide (DMF) solutions. HBO at S0 shows a reversible deprotonation reaction leading to the production of anionic forms. However, for 6A-HBO and 5A-HBO, DMF containing KOH is necessary to produce the anions. Excited HBO in DMF exhibits intra- as well as inter-molecular proton transfer (ESIPT and ESPT) reactions. With excitation at 330 nm, we observed the open-enol, anti-enol and keto forms with different emission and lifetimes (620 ps, 1.5 ns, and 74 ps, respectively), while with the excitation at 433 nm, only the anionic species emission was detected (3.7 ns). Contrary to HBO, 6A-HBO and 5A-HBO do not exhibit any proton transfer process, and only the emissions of the open-enol charge-transferred forms (open-ECT) were observed, which are comparable to those of their methylated derivatives (6A-MBO and 5A-MBO). Femtosecond studies of 6A-MBO and 6A-HBO in DMF indicate that an intramolecular charge-transfer (ICT) reaction (∼80 fs) and solvent relaxation process (2 ps) take place at S1. Remarkably, the photoinduced breaking of the intramolecular hydrogen bond of 6A-HBO and the formation of an intermolecular hydrogen bond with DMF molecules occurs in 80 ps, while for 5A-HBO, this process occurs in less than 10 ps. In this study, we have demonstrated that the presence and position of the amino group in the HBO framework change both the S0 and S1 behaviours of the intramolecular H-bonds; a result which might be useful for the design and better understanding of supramolecular systems based on intra- and intermolecular H-bonds.
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Affiliation(s)
- Noemí Alarcos
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S.N., 45071 Toledo, Spain.
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Gutierrez M, Alarcos N, Liras M, Sánchez F, Douhal A. Switching to a Reversible Proton Motion in a Charge-Transferred Dye. J Phys Chem B 2015; 119:552-62. [DOI: 10.1021/jp511345z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Mario Gutierrez
- Departamento
de Química Física, Facultad de Ciencias Ambientales
y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S.N., 45071 Toledo, Spain
| | - Noemí Alarcos
- Departamento
de Química Física, Facultad de Ciencias Ambientales
y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S.N., 45071 Toledo, Spain
| | - Marta Liras
- Instituto
de Química Orgánica General, IQOG-CSIC, Juan de la
Cierva, 3, 28006 Madrid, Spain
| | - Félix Sánchez
- Instituto
de Química Orgánica General, IQOG-CSIC, Juan de la
Cierva, 3, 28006 Madrid, Spain
| | - Abderrazzak Douhal
- Departamento
de Química Física, Facultad de Ciencias Ambientales
y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Avenida Carlos III, S.N., 45071 Toledo, Spain
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