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Jansen-van Vuuren RD, Liu S, Miah MAJ, Cerkovnik J, Košmrlj J, Snieckus V. The Versatile and Strategic O-Carbamate Directed Metalation Group in the Synthesis of Aromatic Molecules: An Update. Chem Rev 2024; 124:7731-7828. [PMID: 38864673 PMCID: PMC11212060 DOI: 10.1021/acs.chemrev.3c00923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 04/26/2024] [Accepted: 05/08/2024] [Indexed: 06/13/2024]
Abstract
The aryl O-carbamate (ArOAm) group is among the strongest of the directed metalation groups (DMGs) in directed ortho metalation (DoM) chemistry, especially in the form Ar-OCONEt2. Since the last comprehensive review of metalation chemistry involving ArOAms (published more than 30 years ago), the field has expanded significantly. For example, it now encompasses new substrates, solvent systems, and metalating agents, while conditions have been developed enabling metalation of ArOAm to be conducted in a green and sustainable manner. The ArOAm group has also proven to be effective in the anionic ortho-Fries (AoF) rearrangement, Directed remote metalation (DreM), iterative DoM sequences, and DoM-halogen dance (HalD) synthetic strategies and has been transformed into a diverse range of functionalities and coupled with various groups through a range of cross-coupling (CC) strategies. Of ultimate value, the ArOAm group has demonstrated utility in the synthesis of a diverse range of bioactive and polycyclic aromatic compounds for various applications.
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Affiliation(s)
- Ross D. Jansen-van Vuuren
- Department
of Chemistry, Queen’s University, Chernoff Hall, 9 Bader Lane, Kingston, Ontario K7K 2N1, Canada
- Faculty
of Chemistry and Chemical Technology, University
of Ljubljana, Večna pot 113, 1000 Ljubljana, Slovenia
| | - Susana Liu
- Department
of Chemistry, Queen’s University, Chernoff Hall, 9 Bader Lane, Kingston, Ontario K7K 2N1, Canada
| | - M. A. Jalil Miah
- Department
of Chemistry, Rajshahi University, Rajshahi-6205, Bangladesh
| | - Janez Cerkovnik
- Faculty
of Chemistry and Chemical Technology, University
of Ljubljana, Večna pot 113, 1000 Ljubljana, Slovenia
| | - Janez Košmrlj
- Faculty
of Chemistry and Chemical Technology, University
of Ljubljana, Večna pot 113, 1000 Ljubljana, Slovenia
| | - Victor Snieckus
- Department
of Chemistry, Queen’s University, Chernoff Hall, 9 Bader Lane, Kingston, Ontario K7K 2N1, Canada
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2
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Kim JS, Kwon SH, Kim YS. Probing impact of interface mixing on the charge carrier dynamics of a solution-processed organic light emitting diode via impedance spectroscopy. NANOSCALE 2023; 15:1529-1536. [PMID: 36624999 DOI: 10.1039/d2nr05261j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Recently, several studies have revealed that the thermal annealing process induces intermixing at the interfaces of multilayered solution-processed organic light emitting diodes (OLEDs) and enhances their device performance. Depth profiling measurements, such as neutron reflectometry, have meticulously shown that significant intermixing occurs when the annealing temperature exceeds the glass transition temperature (Tg) of OLED materials. However, electrical characterization to unveil the physical origins of the correlation between interfacial characteristics and device performance is still lacking. Here, we introduce impedance spectroscopy (IS) analysis to examine the thermally induced modifications of charge carrier dynamics in a solution-processed bilayer OLED, consisting of an emission layer and an electron transporting layer (ETL). The characteristic relaxation frequency and capacitance extracted from the capacitance-frequency spectra of the OLEDs thermally annealed at varying temperatures were utilized to separately assess the conductance of the ETL and interfacial carrier accumulation, respectively. The results show that the improved charge transport of the ETL upon thermal annealing is mainly responsible for the performance enhancement since annealing the OLEDs at a temperature above the Tg of the ETL, at which significant intermixing occurs, promotes non-radiative trap-assisted recombination and thereby deteriorates the current efficiency. The proposed IS analysis exhibits that IS can separately probe the charge transport, interfacial charge accumulation and recombination process which are crucial for accurate analysis of charge carrier dynamics in solution-processed OLEDs and can thus be utilized to identify the key factors limiting the device performance.
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Affiliation(s)
- Ji Soo Kim
- Department of Applied Bioengineering, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 08826, Republic of Korea.
| | - Soon-Hyung Kwon
- Display Research Center, Korea Electronics Technology Institute, 25 Saenari-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13509, Republic of Korea.
| | - Youn Sang Kim
- Department of Applied Bioengineering, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 08826, Republic of Korea.
- Department of Chemical and Biological Engineering and Institute of Chemical Processes, College of Engineering, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 08826, Republic of Korea
- Advanced Institutes of Convergence Technology, 145 Gwanggyo-ro, Yeongtong-gu, Suwon, 16229, Republic of Korea
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McEwan JA, Clulow AJ, Nelson A, Krause-Heuer AM, Jansen-van Vuuren RD, Burn PL, Gentle IR. Diffusion in Organic Film Stacks Containing Solution-Processed Phosphorescent Poly(dendrimer) Dopants. ACS APPLIED MATERIALS & INTERFACES 2021; 13:30910-30920. [PMID: 34170676 DOI: 10.1021/acsami.1c05940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Efficient organic light-emitting diodes (OLEDs) consist of an emissive layer comprising a blend of a light-emitting and host material in contact with one or more charge transporting layers. The distribution of the active material in the guest-host emissive layer blend and the changes that may occur upon thermal annealing are two important factors in determining the stability and efficiency of OLEDs. We have combined neutron reflectometry and photoluminescence measurements to investigate the structures of films comprising an emissive layer containing a phosphorescent poly(dendrimer) material blended with 4,4'-N,N'-di(carbazolyl)biphenyl. This combination has been shown to give rise to highly efficient OLEDs. Here, we show that the emissive poly(dendrimer) material was not uniformly distributed in the host, but formed a concentration gradient within the emissive layer. Upon heating, the adjacent electron transport layer was found to intermix with the emissive layer, accompanied by changes in the material distribution in the emissive layer. The intermixing of the materials led to a decrease in the photoluminescence from the poly(dendrimer) within the film. The decrease in the photoluminescence was ascribed to an increase in interchromophore interactions that could arise from a conformational change of the poly(dendrimer) or phase separation leading to aggregation. The results indicate that, while uniform mixing of the guest and host is not essential for efficiency, the thermal stabilities of both host and charge transport materials are important for device durability.
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Affiliation(s)
- Jake A McEwan
- Centre for Organic Photonics & Electronics, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Andrew J Clulow
- Centre for Organic Photonics & Electronics, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Andrew Nelson
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
| | - Anwen M Krause-Heuer
- National Deuteration Facility Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
| | - Ross D Jansen-van Vuuren
- Centre for Organic Photonics & Electronics, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Paul L Burn
- Centre for Organic Photonics & Electronics, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Ian R Gentle
- Centre for Organic Photonics & Electronics, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
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Ban X, Chen F, Zhao Y, Zhu A, Tong Z, Jiang W, Sun Y. Strategy for the Realization of Highly Efficient Solution-Processed All-Fluorescence White OLEDs-Encapsulated Thermally Activated Delayed Fluorescent Yellow Emitters. ACS APPLIED MATERIALS & INTERFACES 2018; 10:37335-37344. [PMID: 30303007 DOI: 10.1021/acsami.8b13101] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Fabrication of highly efficient all thermally activated delayed fluorescence (TADF) white organic light-emitting diodes (WOLEDs) through solution-process still remains a big challenge. Here, two encapsulated TADF molecules with a small singlet-triplet energy gap (Δ EST) and high photoluminescence quantum yield (PLQY) were designed and synthesized as yellow emitters for solution-processed WOLEDs. The high current, power, and external quantum efficiencies of 41.6 cd A-1, 30.4 lm W-1, and 17.3% were achieved for the solution-processed all-fluorescence WOLEDs with a single-emission layer. In contrast, even with the same Δ EST and PLQY, the corresponding unencapsulated parent emitters will account for nearly 50% loss of the potential device efficiency. This is for the first time that the small molecular TADF blue host and TADF yellow guest are used to construct solution-processed all-fluorescence WOLEDs, which exhibit high efficiency comparable with most of the vacuum-deposited all-fluorescence white devices. These results not only demonstrate the great potential of TADF emitters in achieving highly efficient solution-processed WOLEDs, but also testify the key role of molecular encapsulation in reducing polar-exciton quenching and enhancing electroluminescence performance.
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Affiliation(s)
- Xinxin Ban
- Jiangsu Key Laboratory of Function Control Technology for Advanced Materials, School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , Jiangsu 222005 , China
| | - Feng Chen
- Jiangsu Key Laboratory of Function Control Technology for Advanced Materials, School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , Jiangsu 222005 , China
| | - Yaqing Zhao
- Jiangsu Key Laboratory of Function Control Technology for Advanced Materials, School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , Jiangsu 222005 , China
| | - Aiyun Zhu
- Jiangsu Key Laboratory of Function Control Technology for Advanced Materials, School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , Jiangsu 222005 , China
| | - Zhiwei Tong
- Jiangsu Key Laboratory of Function Control Technology for Advanced Materials, School of Chemical Engineering , Huaihai Institute of Technology , Lianyungang , Jiangsu 222005 , China
| | - Wei Jiang
- School of Chemistry and Chemical Engineering , Southeast University , Nanjing , Jiangsu 211189 , China
| | - Yueming Sun
- School of Chemistry and Chemical Engineering , Southeast University , Nanjing , Jiangsu 211189 , China
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