1
|
Benítez M, Buil ML, Esteruelas MA, López AM, Martín-Escura C, Oñate E. C-H, N-H, and O-H Bond Activations to Prepare Phosphorescent Hydride-Iridium(III)-Phosphine Emitters with Photocatalytic Achievement in C-C Coupling Reactions. Inorg Chem 2024; 63:6346-6361. [PMID: 38546839 DOI: 10.1021/acs.inorgchem.4c00115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Complex IrH5(PiPr3)2 (1) activates two different σ-bonds of 3-phenoxy-1-phenylisoquinoline, 2-(1H-benzimidazol-2-yl)-6-phenylpyridine, 2-(1H-indol-2-yl)-6-phenylpyridine, 2-(2-hydroxyphenyl)-6-phenylpyridine, N-(2-hydroxyphenyl)-N'-phenylimidazolylidene, and 1,3-di(2-pyridyl)-4,6-dimethylbenzene to give IrH{κ3-C,N,C-[C6H4-isoqui-O-C6H4]}(PiPr3)2 (2), IrH{κ3-N,N,C-[NBzim-py-C6H4]}(PiPr3)2 (3), IrH{κ3-N,N,C-[Ind-py-C6H4]}(PiPr3)2 (4), IrH{κ3-C,N,O-[C6H4-py-C6H4O]}(PiPr3)2 (5), IrH{κ3-C,C,O-[C6H4-Im-C6H4O]}(PiPr3)2 (6), and IrH{κ3-N,C,C-[py-C6HMe2-C5H3N]}(PiPr3)2 (7), respectively. The activations are sequential, with the second generally being the slowest. Accordingly, dihydride intermediates IrH2{κ2-C,N-[C6H4-isoqui-O-C6H5]}(PiPr3)2 (2d), IrH2{κ2-N,N-[NBzim-py-C6H5]}(PiPr3)2 (3d), IrH2{κ2-N,N-[Ind-py-C6H5]}(PiPr3)2 (4d), and IrH2{κ2-N,C-[py-C6HMe2-py]}(PiPr3)2 (7d) were characterized spectroscopically. Complexes 3 and 5 are green phosphorescent emitters upon photoexcitation, exhibiting good absorption over a wide range of wavelengths, emission quantum yields about 0.70 in solution, long enough lifetimes (10-17 μs), and reversible electrochemical behavior. In agreement with these features, complex 3 promotes the photocatalytic α-amino C(sp3)-H arylation of N,N-dimethylaniline and N-phenylpiperidine with 1,4-dicyanobenzene and 4-cyanopyridine under blue LED light irradiation. The C-C coupling products are isolated in high yields with only 2 mol % of photocatalyst after 24 h.
Collapse
Affiliation(s)
- María Benítez
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza-CSIC, Zaragoza 50009, Spain
| | - María L Buil
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza-CSIC, Zaragoza 50009, Spain
| | - Miguel A Esteruelas
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza-CSIC, Zaragoza 50009, Spain
| | - Ana M López
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza-CSIC, Zaragoza 50009, Spain
| | - Cristina Martín-Escura
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza-CSIC, Zaragoza 50009, Spain
| | - Enrique Oñate
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza-CSIC, Zaragoza 50009, Spain
| |
Collapse
|
2
|
Jiang C, Cañada LM, Nguyen NB, Halamicek MDS, Nguyen SH, Teets TS. Substituent-Dependent Azide Addition to Isocyanides Generates Strongly Luminescent Iridium Complexes. J Am Chem Soc 2023; 145:1227-1235. [PMID: 36603163 DOI: 10.1021/jacs.2c11062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Ligand-centered functionalization reactions offer diverse strategies to prepare luminescent organometallic compounds. These compounds can have unique structures that are not accessible via traditional coordination chemistry and can possess enhanced or unusual photophysical properties. Here we show that bis-cyclometalated iridium bis-isocyanide complexes (1) react with azide (N3-) to form novel luminescent structures. The fate of the reaction with azide is determined primarily by the substituent on the aryl isocyanide. Those with electron-withdrawing substituents (CF3 or NO2) react with 1 equiv of azide followed by N2 extrusion, forming aryl cyanamido products (2). With electron-donating groups on the aryl isocyanide the reactivity is more diverse, and three outcomes are possible. In two cases, the isocyanide and azide undergo a [3 + 2] cycloaddition to form a C-bound tetrazolato structure (3). In three other cases, 2 equiv of azide are involved in the formation of a previously unobserved structure, where a tetrazolato and aryl cyanamido couple and rearrange to form a chelating ligand comprised of an N-bound tetrazolato and an acyclic diaminocarbene (4). Finally, a bimetallic aryl cyanamido complex (5) is isolated in one case. All compounds are luminescent, some with exceptional photoluminescence quantum yields as high as 0.81 in solution for sky-blue emission, and 0.87 for yellow emission and 0.65 for orange-red emission in polymer films.
Collapse
Affiliation(s)
- Chenggang Jiang
- Department of Chemistry, University of Houston, 3585 Cullen Blvd. Room 112, Houston, Texas 77204-5003, United States
| | - Louise M Cañada
- Department of Chemistry, University of Houston, 3585 Cullen Blvd. Room 112, Houston, Texas 77204-5003, United States
| | - Ngoc Bao Nguyen
- Department of Chemistry, University of Houston, 3585 Cullen Blvd. Room 112, Houston, Texas 77204-5003, United States
| | - Michael D S Halamicek
- Department of Chemistry, University of Houston, 3585 Cullen Blvd. Room 112, Houston, Texas 77204-5003, United States
| | - Sami H Nguyen
- Department of Chemistry, University of Houston, 3585 Cullen Blvd. Room 112, Houston, Texas 77204-5003, United States
| | - Thomas S Teets
- Department of Chemistry, University of Houston, 3585 Cullen Blvd. Room 112, Houston, Texas 77204-5003, United States
| |
Collapse
|
3
|
Benítez M, Buil ML, Esteruelas MA, Izquierdo S, Oñate E, Tsai JY. Acetylides for the Preparation of Phosphorescent Iridium(III) Complexes: Iridaoxazoles and Their Transformation into Hydroxycarbenes and N,C(sp3),C(sp2),O-Tetradentate Ligands. Inorg Chem 2022; 61:19597-19611. [PMID: 36416194 PMCID: PMC9949702 DOI: 10.1021/acs.inorgchem.2c03522] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The preparation of three families of phosphorescent iridium(III) emitters, including iridaoxazole derivatives, hydroxycarbene compounds, and N,C(sp3),C(sp2),O-tetradentate containing complexes, has been performed starting from dimers cis-[Ir(μ2-η2-C≡CR){κ2-C,N-(MeC6H3-py)}2]2 (R = tBu (1a), Ph (1b)). Reactions of 1a with benzamide, acetamide, phenylacetamide, and trifluoroacetamide lead to the iridaoxazole derivatives Ir{κ2-C,O-[C(CH2tBu)NC(R)O]}{κ2-C,N-(MeC6H3-py)}2 (R = Ph (2), Me (3), CH2Ph (4), CF3 (5)) with a fac disposition of carbons and heteroatoms around the metal center. In 2-methyltetrahydrofuran and dichloromethane, water promotes the C-N rupture of the IrC-N bond of the iridaoxazole ring of 3-5 to form amidate-iridium(III)-hydroxycarbene derivatives Ir{κ1-N-[NHC(R)O]}{κ2-C,N-(MeC6H3-py)}2{═C(CH2tBu)OH} (R = Me (6), CH2Ph (7), CF3 (8)). In contrast to 1a, dimer 1b reacts with benzamide and acetamide to give Ir{κ4-N,C,C',O-[py-MeC6H3-C(CH2-C6H4)NHC(R)O]}{κ2-C,N-(MeC6H3-py)}(R = Ph (9), Me (10)), which bear a N,C(sp3),C(sp2),O-tetradentate ligand resulting from a triple coupling (an alkynyl ligand, an amide, and a coordinated aryl group) and a C-H bond activation at the metal coordination sphere. Complexes 2-4 and 6-10 are emissive upon photoexcitation, in orange (2-4), green (6-8), and yellow (9 and 10) regions, with quantum yields between low and moderate (0.01-0.50) and short lifetimes (0.2-9.0 μs).
Collapse
Affiliation(s)
- María Benítez
- Departamento
de Química Inorgánica, Instituto de Síntesis
Química y Catálisis Homogénea (ISQCH), Centro
de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza−CSIC, 50009 Zaragoza, Spain
| | - María L. Buil
- Departamento
de Química Inorgánica, Instituto de Síntesis
Química y Catálisis Homogénea (ISQCH), Centro
de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza−CSIC, 50009 Zaragoza, Spain
| | - Miguel A. Esteruelas
- Departamento
de Química Inorgánica, Instituto de Síntesis
Química y Catálisis Homogénea (ISQCH), Centro
de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza−CSIC, 50009 Zaragoza, Spain,
| | - Susana Izquierdo
- Departamento
de Química Inorgánica, Instituto de Síntesis
Química y Catálisis Homogénea (ISQCH), Centro
de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza−CSIC, 50009 Zaragoza, Spain
| | - Enrique Oñate
- Departamento
de Química Inorgánica, Instituto de Síntesis
Química y Catálisis Homogénea (ISQCH), Centro
de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza−CSIC, 50009 Zaragoza, Spain
| | - Jui-Yi Tsai
- Universal
Display Corporation, Ewing, New Jersey 08618, United States
| |
Collapse
|
4
|
Jiang C, Cañada LM, Nguyen NB, Teets TS. Luminescent “Chugaev-type” Cyclometalated Iridium(III) Complexes Synthesized by Nucleophilic Addition of Hydrazine. J Organomet Chem 2022. [DOI: 10.1016/j.jorganchem.2022.122561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
5
|
Nguyen YH, Soares JV, Nguyen SH, Wu Y, Wu JI, Teets TS. Platinum(II)-Substituted Phenylacetylide Complexes Supported by Acyclic Diaminocarbene Ligands. Inorg Chem 2022; 61:8498-8508. [PMID: 35609301 DOI: 10.1021/acs.inorgchem.2c00510] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We introduce phosphorescent platinum aryl acetylide complexes supported by tert-butyl-isocyanide and strongly σ-donating acyclic diaminocarbene (ADC) ligands. The precursor complexes cis-[Pt(CNtBu)2(C≡CAr)2] (4a-4f) are treated with diethylamine, which undergoes nucleophilic addition with one of the isocyanides to form the cis-[Pt(CNtBu)(ADC)(C≡CAr)2] complexes (5a-5f). The new compounds incorporate either electron-donating groups (4-OMe and 4-NMe2) or electron-withdrawing groups [3,5-(OMe)2, 3,5-(CF3)2, 4-CN, and 4-NO2] on the aryl acetylide. Experimental HOMO-LUMO gaps, estimated from cyclic voltammetry, span the range of 2.68-3.61 eV and are in most cases smaller than the unsubstituted parent complex, as corroborated by DFT. In the ADC complexes, peak photoluminescence wavelengths span the range of 428 nm (2a, unsubstituted phenylacetylide) to 525 nm (5f, 4-NO2-substituted), with the substituents inducing a red shift in all cases. The phosphorescence E0,0 values and electrochemical HOMO-LUMO gaps are loosely correlated, showing that both can be reduced by either electron-donating or electron-withdrawing substituents on the aryl acetylides. The photoluminescence quantum yields in the ADC complexes are between 0.044 and 0.31 and the lifetimes are between 4.8 and 14 μs, a factor of 1.8-10× higher (for ΦPL) and 1.2-3.6× longer (for τ) than the respective isocyanide precursor (ΦPL = 0.014-0.12, τ = 2.8-8.2 μs).
Collapse
Affiliation(s)
- Yennie H Nguyen
- Department of Chemistry, University of Houston, 3585 Cullen Blvd., Room 112, Houston, Texas 77204-5003, United States
| | - João Vitor Soares
- Department of Chemistry, University of Houston, 3585 Cullen Blvd., Room 112, Houston, Texas 77204-5003, United States
| | - Sami H Nguyen
- Department of Chemistry, University of Houston, 3585 Cullen Blvd., Room 112, Houston, Texas 77204-5003, United States
| | - Yanyu Wu
- Department of Chemistry, University of Houston, 3585 Cullen Blvd., Room 112, Houston, Texas 77204-5003, United States
| | - Judy I Wu
- Department of Chemistry, University of Houston, 3585 Cullen Blvd., Room 112, Houston, Texas 77204-5003, United States
| | - Thomas S Teets
- Department of Chemistry, University of Houston, 3585 Cullen Blvd., Room 112, Houston, Texas 77204-5003, United States
| |
Collapse
|
6
|
Adamovich V, Benítez M, Boudreault PL, Buil ML, Esteruelas MA, Oñate E, Tsai JY. Alkynyl Ligands as Building Blocks for the Preparation of Phosphorescent Iridium(III) Emitters: Alternative Synthetic Precursors and Procedures. Inorg Chem 2022; 61:9019-9033. [PMID: 35438993 PMCID: PMC9490848 DOI: 10.1021/acs.inorgchem.2c00197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Alkynyl ligands stabilize
dimers [Ir(μ-X)(3b)2]2 with a cis disposition
of the heterocycles of the 3b
ligands, in contrast to chloride. Thus, the complexes of this class—cis-[Ir(μ2-η2-C≡CPh){κ2-C,N-(C6H4-Isoqui)}2]2 (Isoqui = isoquinoline)
and cis-[Ir(μ2-η2-C≡CR){κ2-C,N-(MeC6H3-py)}2]2 (R =
Ph, tBu)—have been prepared in
high yields, starting from the dihydroxo-bridged dimers trans-[Ir(μ-OH){κ2-C,N-(C6H4-Isoqui)}2]2 and trans-[Ir(μ-OH){κ2-C,N-(MeC6H3-py)}2]2 and terminal alkynes. Subsequently, the acetylide ligands
have been employed as building blocks to prepare the orange and green
iridium(III) phosphorescent emitters, Ir{κ2-C,N-[C(CH2Ph)Npy]}{κ2-C,N-(C6H4-Isoqui)}2 and Ir{κ2-C,N-[C(CH2R)Npy]}{κ2-C,N-(MeC6H3-py)}2 (R = Ph, tBu), respectively,
with an octahedral structure of fac carbon and nitrogen
atoms. The green emitter Ir{κ2-C,N-[C(CH2tBu)Npy]}{κ2-C,N-(MeC6H3-py)}2 reaches 100% of quantum
yield in both the poly(methyl methacrylate) (PMMA) film and 2-MeTHF
at room temperature. In organic light-emitting diode (OLED) devices,
it demonstrates very saturated green emission at a peak wavelength
of 500 nm, with an external quantum efficiency (EQE) of over 12% or
luminous efficacy of 30.7 cd/A. Acetylide
ligands have been employed as building blocks
to prepare orange and green iridium(III) phosphorescent emitters,
with an octahedral structure of fac carbon and nitrogen
atoms. In OLED devices, the emitter Ir{κ2-C,N-[C(CH2tBu)Npy]}{κ2-C,N-(MeC6H3-py)}2 demonstrates
very saturated green emission at a peak wavelength of 500 nm, with
a luminous efficacy of 30.7 cd/A.
Collapse
Affiliation(s)
- Vadim Adamovich
- Universal Display Corporation, Ewing, New Jersey 08618, United States
| | - María Benítez
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza─CSIC, 50009 Zaragoza, Spain
| | | | - María L Buil
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza─CSIC, 50009 Zaragoza, Spain
| | - Miguel A Esteruelas
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza─CSIC, 50009 Zaragoza, Spain
| | - Enrique Oñate
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza─CSIC, 50009 Zaragoza, Spain
| | - Jui-Yi Tsai
- Universal Display Corporation, Ewing, New Jersey 08618, United States
| |
Collapse
|
7
|
Ge ZR, Tong X, Huang YC, Li WH, Li HY, Lu AD, Li TY. Highly Luminescent Dinuclear Iridium(III) Complexes Containing Phenanthroline-Based Neutral Ligands as Chemosensors for Cu 2+ Ion. Organometallics 2022. [DOI: 10.1021/acs.organomet.1c00617] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Ze-Rong Ge
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China
| | - Xin Tong
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China
| | - Yi-Chuan Huang
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China
| | - Wen-Hao Li
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China
| | - Hong-Yan Li
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China
| | - Ai-Dang Lu
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China
| | - Tian-Yi Li
- School of Chemistry and Biological Engineering, Department of Physical Chemistry, University of Science and Technology Beijing, Beijing, 100083, China
| |
Collapse
|
8
|
Kinzhalov MA, Luzyanin KV. Synthesis and Contemporary Applications of Platinum Group Metals Complexes with Acyclic Diaminocarbene Ligands (Review). RUSS J INORG CHEM+ 2022. [DOI: 10.1134/s0036023622010065] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
9
|
Kinzhalov MA, Grachova EV, Luzyanin KV. Tuning the luminescence of transition metal complexes with acyclic diaminocarbene ligands. Inorg Chem Front 2022. [DOI: 10.1039/d1qi01288f] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Organometallics featuring acyclic diaminocarbene ligands have recently emerged as powerful emitters for use in electroluminescent technologies.
Collapse
Affiliation(s)
- Mikhail A. Kinzhalov
- St Petersburg University, 7/9 Universitetskaya Nab., Saint Petersburg, 199034, Russia
| | - Elena V. Grachova
- St Petersburg University, 7/9 Universitetskaya Nab., Saint Petersburg, 199034, Russia
| | | |
Collapse
|
10
|
Sutton GD, Olumba ME, Nguyen YH, Teets TS. The diverse functions of isocyanides in phosphorescent metal complexes. Dalton Trans 2021; 50:17851-17863. [PMID: 34787613 DOI: 10.1039/d1dt03312c] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In this Perspective, we highlight many examples of photoluminescent metal complexes supported by isocyanides, with an emphasis on recent developments including several from our own group. Work in this field has shown that the isocyanide can play important structural roles, both as a terminal ligand and as a bridging ligand for polynuclear structures, and can influence the excited-state character and excited-state dynamics. In addition, there are many examples of isocyanide-supported complexes where the isocyanide serves as a chromophoric ligand, meaning the low-energy excited states that are important in the photochemistry are partially or completely localized on the isocyanide. Finally, an emerging trend in the design of luminescent compounds is to use the isocyanide as an electrophilic precursor, converted to an acyclic carbene by nucleophilic addition which imparts certain photophysical advantages. This Perspective aims to show the diverse roles played by isocyanides in the design of luminescent compounds, showcasing the recent developments that have led to a substantial growth in fundamental knowledge, function, and applications related to photoluminescence.
Collapse
Affiliation(s)
- Gregory D Sutton
- University of Houston, Department of Chemistry, 3585 Cullen Blvd., Room 112, Houston, TX 77204-5003, USA.
| | - Morris E Olumba
- University of Houston, Department of Chemistry, 3585 Cullen Blvd., Room 112, Houston, TX 77204-5003, USA.
| | - Yennie H Nguyen
- University of Houston, Department of Chemistry, 3585 Cullen Blvd., Room 112, Houston, TX 77204-5003, USA.
| | - Thomas S Teets
- University of Houston, Department of Chemistry, 3585 Cullen Blvd., Room 112, Houston, TX 77204-5003, USA.
| |
Collapse
|
11
|
Martínez-Junquera M, Lalinde E, Moreno MT, Alfaro-Arnedo E, López IP, Larráyoz IM, Pichel JG. Luminescent cyclometalated platinum(ii) complexes with acyclic diaminocarbene ligands: structural, photophysical and biological properties. Dalton Trans 2021; 50:4539-4554. [PMID: 33729268 DOI: 10.1039/d1dt00480h] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Four new cyclometalated Pt(ii) complexes bearing acyclic diaminocarbene (ADC) ligands, [Pt(C^N)Cl{C(NHXyl)(NHR)}] [C^N = 2,6-difluorophenylpyridine (dfppy), phenylquinoline (pq); R = Pr 3a, 4a, CH2Ph 3b, 4b], were prepared by the nucleophilic attack on the isocyanide [Pt(C^N)Cl(CNXyl)] (C^N = dfppy 1, pq 2) by the corresponding amine RNH2 (R = Pr, CH2Ph). Complexes 3 show in their 1H NMR spectra in CDCl3 a notable concentration dependence, with a clear variation of the δH (NHXyl) signal, suggesting an assembling process implying donor-acceptor NHXylCl bonding, also supported by 1D-PGSE (Pulse Field Gradient Spin Echo) and 2D-DOSY (Diffusion Ordered Spectroscopy) NMR experiments in solution and X-ray diffraction studies. The intermolecular interactions in compounds 3a and 3b were studied by using Hirshfeld surface analysis and Non-Covalent Interaction (NCI) methods on their X-ray structures. Their photophysical properties were investigated by absorption and emission spectroscopies and also by TD-DFT calculations performed on 3a and 4b. These complexes show green (3) or orange (4) phosphorescence, attributed to a mixed 3IL/3MLCT excited state. The carbene ligand does not affect the emission maxima but it produces an increase of the quantum yields in relation to the isocyanide in the precursors. In fluid solutions, the emission is not concentration-dependent, but the complexes may show aggregation induced emission as detailed for complexes 3a and 4a. In addition, cytotoxicity studies in the human cell lines A549 (lung carcinoma) and HeLa (cervix carcinoma) showed good activity for these complexes and 3a, 3b and 4a exhibit a strong effect on DNA electrophoretic mobility. To the best of our knowledge, compounds 3 and 4 represent the first examples of cycloplatinated complexes bearing acyclic diamino carbenes with antiproliferative properties.
Collapse
Affiliation(s)
- Mónica Martínez-Junquera
- Departamento de Química-Centro de Síntesis Química de La Rioja, (CISQ), Universidad de La Rioja, 26006, Logroño, Spain.
| | | | | | | | | | | | | |
Collapse
|
12
|
Popov RA, Mikherdov AS, Novikov AS, Myznikov LV, Boyarskiy VP. Pd II- and Pt II-mediated coupling of aryl isocyanides with N-heterocyclic thiones. NEW J CHEM 2021. [DOI: 10.1039/d0nj05386d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A PdII- and PtII-mediated reaction of aryl isocyanides with N-heterocyclic thiones results in a previously undescribed type of regioselectivity for ambident nucleophile addition to coordinated isocyanides.
Collapse
Affiliation(s)
- Roman A. Popov
- Saint Petersburg State University
- Universitetskaya Nab. 7/9
- Saint Petersburg 199034
- Russian Federation
| | - Alexander S. Mikherdov
- Saint Petersburg State University
- Universitetskaya Nab. 7/9
- Saint Petersburg 199034
- Russian Federation
| | - Alexander S. Novikov
- Saint Petersburg State University
- Universitetskaya Nab. 7/9
- Saint Petersburg 199034
- Russian Federation
| | - Leonid V. Myznikov
- Saint-Petersburg State Institute of Technology
- Moskovsky ave. 26
- St. Petersburg 190013
- Russian Federation
| | - Vadim P. Boyarskiy
- Saint Petersburg State University
- Universitetskaya Nab. 7/9
- Saint Petersburg 199034
- Russian Federation
| |
Collapse
|
13
|
Boudreault PLT, Esteruelas MA, López AM, Oñate E, Raga E, Tsai JY. Insertion of Unsaturated C-C Bonds into the O-H Bond of an Iridium(III)-Hydroxo Complex: Formation of Phosphorescent Emitters with an Asymmetrical β-Diketonate Ligand. Inorg Chem 2020; 59:15877-15887. [PMID: 33059453 DOI: 10.1021/acs.inorgchem.0c02395] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A synthetic methodology to prepare iridium(III) emitters of the class [3b+3b+3b'] with two ortho-metalated 1-phenylisoquinolines and an asymmetrical β-diketonate has been discovered. The abstraction of the chloride ligands of the dimer [Ir(μ-Cl){κ2-C,N-(C6H4-isoqui)}2]2 (1, C6H5-isoqui = 1-phenylisoquinoline) with AgBF4 in acetone and the subsequent addition of water to the resulting solution affords the water solvate mononuclear complex [Ir{κ2-C,N-(C6H4-isoqui)}2(H2O)2]BF4 (2), which reacts with KOH to give the dihydroxo-bridged dimer [Ir(μ-OH){κ2-C,N-(C6H4-isoqui)}2]2 (3). Treatment of the latter with dimethyl acetylenedicarboxylate leads to Ir{κ2-C,N-(C6H4-isoqui)}2{κ2-O,O-[OC(CO2CH3)CHC(OCH3)O]} (4), as a result of the anti-addition of the O-H bond of a mononuclear [Ir(OH){κ2-C,N-(C6H4-isoqui)}2] fragment to the C-C triple bond of the alkyne and the coordination of one of the carboxylate substituents to the metal center. Complex 3 also reacts with α,β-unsaturated ketones. The reaction with 3-(4-methylphenyl)-1-phenylprop-2-en-1-one affords Ir{κ2-C,N-(C6H4-isoqui)}2{κ2-O,O-[OC(C6H5)CHC(p-C6H4Me)O]} (5), whereas methyl vinyl ketone gives a mixture of Ir{κ2-C,N-(C6H4-isoqui)}2{κ2-O,O-[OC(CH3)CHCHO]} (6) and Ir{κ2-C,N-(C6H4-isoqui)}2{κ2-O,O-[OC(CH3)CHC(CH═CH2)O]} (7). Complexes 5 and 6 are the result of the addition of the O-H bond of the mononuclear [Ir(OH){κ2-C,N-(C6H4-isoqui)}2] fragment to the C-C double bond of the α,β-unsaturated ketones and the coordination of the carbonyl group to the iridium center, to generate O,O-chelates which lose molecular hydrogen to aromatize into the asymmetrical β-diketonate ligands. Complexes 4-7 are phosphorescent emitters in the red spectral region (599-672 nm) in doped poly(methyl methacrylate) (PMMA) film at 5 wt % at room temperature and 2-methyltetrahydrofuran at room temperature and 77 K. They display short lifetimes (0.8-2.5 μs) and quantum yields in both doped PMMA films and in 2-methyltetrahydrofuran at room temperature depending on the substituents of the β-diketonate: about 0.6-0.5 for 4 and 6 and ca. 0.35 for 5 and 7.
Collapse
Affiliation(s)
| | - Miguel A Esteruelas
- Departamento de Quı́mica Inorgánica, Instituto de Sı́ntesis Quı́mica y Catálisis Homogénea (ISQCH), Centro de Innovación en Quı́mica Avanzada (ORFEO-CINQA), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| | - Ana M López
- Departamento de Quı́mica Inorgánica, Instituto de Sı́ntesis Quı́mica y Catálisis Homogénea (ISQCH), Centro de Innovación en Quı́mica Avanzada (ORFEO-CINQA), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| | - Enrique Oñate
- Departamento de Quı́mica Inorgánica, Instituto de Sı́ntesis Quı́mica y Catálisis Homogénea (ISQCH), Centro de Innovación en Quı́mica Avanzada (ORFEO-CINQA), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| | - Esther Raga
- Departamento de Quı́mica Inorgánica, Instituto de Sı́ntesis Quı́mica y Catálisis Homogénea (ISQCH), Centro de Innovación en Quı́mica Avanzada (ORFEO-CINQA), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| | - Jui-Yi Tsai
- Universal Display Corporation, Ewing, New Jersey 08618, United States
| |
Collapse
|
14
|
Mu G, Wen Z, Wu JIC, Teets TS. Azo-triazolide bis-cyclometalated Ir(iii) complexes via cyclization of 3-cyanodiarylformazanate ligands. Dalton Trans 2020; 49:3775-3785. [PMID: 31774084 DOI: 10.1039/c9dt03914g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work we describe the synthesis of sterically encumbered 1,5-diaryl-3-cyanoformazanate bis-cyclometalated iridium(iii) complexes, two of which undergo redox-neutral cyclization during the reaction to produce carbon-bound 2-aryl-4-arylazo-2H-1,2,3-triazolide ligands. This transformation offers a method for accessing 2-aryl-4-arylazo-2H-1,2,3-triazolide ligands, a heretofore unreported class of chelating ligands. One formazanate complex and both triazolide complexes are structurally characterized by single-crystal X-ray diffraction, with infrared spectroscopy being the primary bulk technique to distinguish the formazanate and triazolide structures. All complexes are further characterized by UV-Vis absorption spectroscopy and cyclic voltammetry, with the triazolide compounds having similar frontier orbital energies to the formazanate complexes but much less visible absorption.
Collapse
Affiliation(s)
- Ge Mu
- University of Houston, Department of Chemistry, 3585 Cullen Blvd. Room 112, Houston, TX, USA 77204-5003.
| | | | | | | |
Collapse
|
15
|
Blue-phosphorescent bis-cyclometalated iridium complexes with aryl isocyanide ancillary ligands. Polyhedron 2020. [DOI: 10.1016/j.poly.2019.114332] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
16
|
Eremina AA, Kinzhalov MA, Katlenok EA, Smirnov AS, Andrusenko EV, Pidko EA, Suslonov VV, Luzyanin KV. Phosphorescent Iridium(III) Complexes with Acyclic Diaminocarbene Ligands as Chemosensors for Mercury. Inorg Chem 2020; 59:2209-2222. [DOI: 10.1021/acs.inorgchem.9b02833] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Anzhelika A. Eremina
- Saint Petersburg State University, 7/9 Universitetskaya Nab., St. Petersburg 199034, Russian Federation
| | - Mikhail A. Kinzhalov
- Saint Petersburg State University, 7/9 Universitetskaya Nab., St. Petersburg 199034, Russian Federation
| | - Evgene A. Katlenok
- Saint Petersburg State University, 7/9 Universitetskaya Nab., St. Petersburg 199034, Russian Federation
| | - Andrey S. Smirnov
- Saint Petersburg State University, 7/9 Universitetskaya Nab., St. Petersburg 199034, Russian Federation
| | - Elena V. Andrusenko
- TheoMAT Group, ITMO University, Lomonosova 9, St. Petersburg 191002, Russian Federation
| | - Evgeny A. Pidko
- TheoMAT Group, ITMO University, Lomonosova 9, St. Petersburg 191002, Russian Federation
- Inorganic Systems Engineering Group, Department of Chemical Engineering, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Vitalii V. Suslonov
- Saint Petersburg State University, 7/9 Universitetskaya Nab., St. Petersburg 199034, Russian Federation
| | - Konstantin V. Luzyanin
- Saint Petersburg State University, 7/9 Universitetskaya Nab., St. Petersburg 199034, Russian Federation
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, United Kingdom
| |
Collapse
|
17
|
|
18
|
Shen Y, Li X, Ye J, Qiu Y. A DFT study on second-order NLO properties of bis-cyclometalated Iridium(III) complexes with chelating dicarbene auxiliary ligands. COMPUT THEOR CHEM 2019. [DOI: 10.1016/j.comptc.2019.112535] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
19
|
Theoretical study on reaction mechanism of synthesis of iridium complexes having cyclometalated acyclic diaminocarbene ancillary ligands. J Mol Model 2019; 25:261. [PMID: 31422481 DOI: 10.1007/s00894-019-4145-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 08/08/2019] [Indexed: 02/02/2023]
Abstract
DFT calculations at the M06-2X level were performed to explore the reaction mechanism for the synthesis of the new cyclometalated iridium(III) complexes with acyclic diaminocarbene ancillary ligands. The solvent effects of the reaction systems have been considered by a single-point energy calculation using the SMD model in the experimental conditions of CH2Cl2 solvent. The calculated results show that the reaction consists of two main steps: the first step is the hydrogen transfer between the two N atoms, and the next step is the closed-loop process of the Ir atom and the aromatic ring ortho to release the HCl molecule. The reaction has a relatively low activation free energy of 17.1-23.2 kcal mol-1, indicating that it is easy to occur under the experimental conditions of Na et al. At the same time, it was found that the aryl para-CF3 substituent has higher reactivity than the corresponding reactant of the NO2 substituent.
Collapse
|
20
|
Na H, Cañada LM, Wen Z, I-Chia Wu J, Teets TS. Mixed-carbene cyclometalated iridium complexes with saturated blue luminescence. Chem Sci 2019; 10:6254-6260. [PMID: 31367300 PMCID: PMC6617658 DOI: 10.1039/c9sc01386e] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 05/26/2019] [Indexed: 12/20/2022] Open
Abstract
A new structural class of mixed-carbene cyclometalated iridium complexes with intense, high-purity blue luminescence are described.
Cyclometalated iridium complexes have emerged as top-performing emitters in organic light-emitting diodes (OLEDs) and other optoelectronic devices. A persistent challenge has been the development of cyclometalated iridium complexes with deep blue luminescence that have the requisite color purity, efficiency, and stability to function in color displays. In this work we report a new class of cyclometalated iridium complexes with saturated blue luminescence. These complexes have the general structure Ir(C^C:NHC)2(C^C:ADC), where C^C:NHC is an N-heterocyclic carbene (NHC) derived cyclometalating ligand and C^C:ADC is a different type of cyclometalating ligand featuring an acyclic diaminocarbene (ADC). The complexes are prepared by a cascade reaction that involves nucleophilic addition of propylamine to an isocyanide precursor followed by base-assisted cyclometalation of the ADC intermediate. All three emit deep blue light with good quantum efficiencies (ΦPL = 0.13–0.48) and color profiles very close to the ideal primary blue standards for color displays.
Collapse
Affiliation(s)
- Hanah Na
- Department of Chemistry , University of Houston , 3585 Cullen Blvd. Room 112 , Houston , TX , USA 77204-5003 .
| | - Louise M Cañada
- Department of Chemistry , University of Houston , 3585 Cullen Blvd. Room 112 , Houston , TX , USA 77204-5003 .
| | - Zhili Wen
- Department of Chemistry , University of Houston , 3585 Cullen Blvd. Room 112 , Houston , TX , USA 77204-5003 .
| | - Judy I-Chia Wu
- Department of Chemistry , University of Houston , 3585 Cullen Blvd. Room 112 , Houston , TX , USA 77204-5003 .
| | - Thomas S Teets
- Department of Chemistry , University of Houston , 3585 Cullen Blvd. Room 112 , Houston , TX , USA 77204-5003 .
| |
Collapse
|
21
|
Kinzhalov MA, Eremina AA, Smirnov AS, Suslonov VV, Kukushkin VY, Luzyanin KV. Cleavage of acyclic diaminocarbene ligands at an iridium(iii) center. Recognition of a new reactivity mode for carbene ligands. Dalton Trans 2019; 48:7571-7582. [DOI: 10.1039/c9dt01138b] [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
A new reactivity mode for acyclic diaminocarbene ligands, viz. competitive cleavage of either C–NH2 or C–NHR bonds in the aminocarbene fragment, is recognized.
Collapse
Affiliation(s)
| | | | | | | | | | - Konstantin V. Luzyanin
- Saint Petersburg State University
- Saint Petersburg
- Russian Federation
- Department of Chemistry
- University of Liverpool
| |
Collapse
|
22
|
Manguin R, Pichon D, Tarrieu R, Vives T, Roisnel T, Dorcet V, Crévisy C, Miqueu K, Favereau L, Crassous J, Mauduit M, Baslé O. A kinetic resolution strategy for the synthesis of chiral octahedral NHC–iridium(iii) catalysts. Chem Commun (Camb) 2019; 55:6058-6061. [DOI: 10.1039/c9cc02434d] [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
The transmetalation reaction of a chiral-bidentate NHC–silver complex to racemic [lr(μ-Cl)(ppy)2]2 operates with kinetic resolution leading to chiral octahedral NHC–iridium(iii) complexes and enantio-enriched bis-cyclometalated iridium(iii) complexes.
Collapse
Affiliation(s)
- Romane Manguin
- Univ. Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS, ISCR – UMR 6226
- F-35000 Rennes
- France
| | - Delphine Pichon
- Univ. Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS, ISCR – UMR 6226
- F-35000 Rennes
- France
| | - Robert Tarrieu
- Univ. Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS, ISCR – UMR 6226
- F-35000 Rennes
- France
| | - Thomas Vives
- Univ. Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS, ISCR – UMR 6226
- F-35000 Rennes
- France
| | | | | | - Christophe Crévisy
- Univ. Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS, ISCR – UMR 6226
- F-35000 Rennes
- France
| | - Karinne Miqueu
- CNRS/Univ. Pau & Pays de l'Adour
- Institut des Sciences Analytiques et de Physico-Chimie pour l’environnement et les Matériaux
- IPREM
- UMR 5254
- Pau
| | | | | | - Marc Mauduit
- Univ. Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS, ISCR – UMR 6226
- F-35000 Rennes
- France
| | - Olivier Baslé
- Univ. Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS, ISCR – UMR 6226
- F-35000 Rennes
- France
| |
Collapse
|
23
|
Herndon JW. The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2017. Coord Chem Rev 2018. [DOI: 10.1016/j.ccr.2018.08.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
24
|
Kinzhalov MA, Parfenova SN, Novikov AS, Katlenok EA, Puzyk MV, Avdontceva MS, Bokach NA. Cyclometalated Iridium(III) Complexes Featuring Disubstituted Cyanamides. ChemistrySelect 2018. [DOI: 10.1002/slct.201802900] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Mikhail A. Kinzhalov
- Saint Petersburg State University7/9 Universitetskaya Nab., Saint Petersburg 199034 Russian Federation
| | - Suzanna N. Parfenova
- Saint Petersburg State University7/9 Universitetskaya Nab., Saint Petersburg 199034 Russian Federation
| | - Alexander S. Novikov
- Saint Petersburg State University7/9 Universitetskaya Nab., Saint Petersburg 199034 Russian Federation
| | - Evgeniy A. Katlenok
- Scientific-research laboratory of Ltd “THP”, Moscow highway 13, Saint Petersburg 196158 Russian Federation
| | - Mikhail V. Puzyk
- Herzen State Pedagogical University, Nab. reki Moiki 48 Saint Petersburg 191186 Russian Federation
| | - Margarita S. Avdontceva
- Saint Petersburg State University7/9 Universitetskaya Nab., Saint Petersburg 199034 Russian Federation
| | - Nadezhda A. Bokach
- Saint Petersburg State University7/9 Universitetskaya Nab., Saint Petersburg 199034 Russian Federation
| |
Collapse
|
25
|
Na H, Lai P, Cañada LM, Teets TS. Photoluminescence of Cyclometalated Iridium Complexes in Poly(methyl methacrylate) Films. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00446] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hanah Na
- Department of Chemistry, University of Houston, 3585 Cullen Boulevard, Room 112, Houston, Texas 77204-5003, United States
| | - Po−Ni Lai
- Department of Chemistry, University of Houston, 3585 Cullen Boulevard, Room 112, Houston, Texas 77204-5003, United States
| | - Louise M. Cañada
- Department of Chemistry, University of Houston, 3585 Cullen Boulevard, Room 112, Houston, Texas 77204-5003, United States
| | - Thomas S. Teets
- Department of Chemistry, University of Houston, 3585 Cullen Boulevard, Room 112, Houston, Texas 77204-5003, United States
| |
Collapse
|
26
|
Na H, Teets TS. Highly Luminescent Cyclometalated Iridium Complexes Generated by Nucleophilic Addition to Coordinated Isocyanides. J Am Chem Soc 2018; 140:6353-6360. [PMID: 29701468 DOI: 10.1021/jacs.8b02416] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In this work, we report a new class of blue-emitting cyclometalated iridium complexes supported by acyclic diaminocarbene (ADC) ancillary ligands. These neutral, tris-chelated complexes are not obtainable via traditional synthesis routes and instead are generated through metal-mediated nucleophilic addition to a metal-bound isocyanide, which is followed by orthometalation of the ADC under mild conditions. Importantly, four of the variants exhibit efficient phosphorescence when immobilized in PMMA matrix, achieving quantum yields of 79% for blue emitters with a 2-(2,4-difluorophenyl)pyridine (F2ppy) C^N ligand and 30-37% for orange emitters with a 2-phenylbenzothiazole (bt) C^N ligand. Electrochemical studies demonstrate significantly higher-lying HOMO levels in the ADC complexes relative to the NHC analogues, a phenomenon that results in enhanced charge-transfer character in the excited states of the ADC complexes. This study demonstrates that ADC ancillary ligands not only give rise to new structures for Ir(III)-based phosphorescent emitters but also are promising targets for use in light-emitting devices and other thin-film optical applications.
Collapse
Affiliation(s)
- Hanah Na
- Department of Chemistry , University of Houston , 3585 Cullen Boulevard, Room 112 , Houston , Texas 77204-5003 , United States
| | - Thomas S Teets
- Department of Chemistry , University of Houston , 3585 Cullen Boulevard, Room 112 , Houston , Texas 77204-5003 , United States
| |
Collapse
|