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1.
Dr. Xuezhao Li Jinguo Wu Dr. Lei Wang Prof. Cheng He Dr. Liyong Chen Dr. Yang Jiao Prof. Chunying Duan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(16):6482-6489
The development of DNA-targeted photodynamic therapy (PDT) agents for cancer treatment has drawn substantial attention. Herein, the design and synthesis of dinuclear IrIII-containing luminescent metallohelices with tunable PDT efficacy that target mitochondrial DNA in cancer cells are reported. The metallohelices are fabricated using dynamic imine-coupling chemistry between aldehyde end-capped fac-Ir(ppy)3 handles and linear alkanediamine spacers, followed by reduction of the imine linkages. The length and odd–even character of the diamine alkyl linker determined the stereochemistry (helicates vs. mesocates). Compared to the helicates, the mesocates exhibit improved apoptosis-induction upon white-light irradiation. Molecular docking studies indicate that the mesocate with a proper length of diamine spacers shows stronger affinity for the minor groove of DNA. This study highlights the potential of DNA-targeting IrIII-containing metallohelices as PDT agents. 相似文献
2.
Giulia Lavarda Daiki Shimizu Toms Torres Atsuhiro Osuka 《Angewandte Chemie (International ed. in English)》2020,59(8):3127-3130
Peripherally metalated porphyrinoids are promising functional π‐systems displaying characteristic optical, electronic, and catalytic properties. In this work, 5‐(2‐pyridyl)‐ and 5,10,15‐tri(2‐pyridyl)‐BIII‐subporphyrins were prepared and used to produce cyclometalated subporphyrins by reactions with [Cp*IrCl2]2, which proceeded through an efficient C?H activation to give the corresponding mono‐ and tri‐IrIII complexes, respectively. While the mono‐IrIII complex was obtained as a diastereomeric mixture, a C3‐symmetric tri‐IrIII complex with the three Cp*‐units all at the concave side was predominantly obtained in a high yield of 90 %, which displays weak NIR phosphorescence even at room temperature in degassed CH2Cl2, differently from the mono‐IrIII complexes. 相似文献
3.
Shujiao Chen Xicheng Liu Zhenzhen Tian Xingxing Ge Hailong Hao Yingying Hao Ying Zhang Yaoqi Xie Laijin Tian Zhe Liu 《应用有机金属化学》2019,33(9)
Four half‐sandwich iridiumIII (IrIII) triphenylamine or carbazole‐modified 2‐phenylpyridine (TPA/Cz‐PhPy) complexes ([(η5‐Cp*)Ir(C^N)Cl]) were synthesized and characterized. Compared with cisplatin, these complexes show higher activity to A549, HepG2 and HeLa cells, with the IC50 values changed from 2.5 ± 0.1 μM to 14.8 ± 2.6 μM. Additionally, complexes could effectively prevent the migration of cancer cells. IrIII TPA/Cz‐PhPy complexes could bind to protein and transport through serum protein, catalyze the oxidation of nicotinamide‐adenine dinucleotid (NADH) and induce the accumulation of reactive oxygen species, and eventually lead to apoptosis, which was also confirmed by flow cytometry. Moreover, prominent targeted fluorescence property confirmed that IrIII TPA/Cz‐PhPy complexes were involved in non‐energy dependent intracellular uptake mechanism, effectively accumulated in lysosomes and damage the integrity of acidic lysosomes, and eventually induce cell death. Above all, TPA/Cz‐appended half‐sandwich IrIII phenylpyridine complexes are promising anticancer agents with dual functions, including migration inhibition and lysosomal damage. 相似文献
4.
Iris de Krom Leen E. E. Broeckx Dr. Martin Lutz Prof. Dr. Christian Müller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(11):3676-3684
The bidentate P,N hybrid ligand 1 allows access for the first time to novel cationic phosphinine‐based RhIII and IrIII complexes, broadening significantly the scope of low‐coordinate aromatic phosphorus heterocycles for potential applications. The coordination chemistry of 1 towards RhIII and IrIII was investigated and compared with the analogous 2,2′‐bipyridine derivative, 2‐(2′‐pyridyl)‐4,6‐diphenylpyridine ( 2 ), which showed significant differences. The molecular structures of [RhCl(Cp*)( 1 )]Cl and [IrCl(Cp*)( 1 )]Cl (Cp*=pentamethylcyclopentadienyl) were determined by means of X‐ray diffraction and confirm the mononuclear nature of the λ3‐phosphinine–RhIII and IrIII complexes. In contrast, a different reactivity and coordination behavior was found for the nitrogen analogue 2 , especially towards RhIII as a bimetallic ion pair [RhCl(Cp*)( 2 )]+[RhCl3(Cp*)]? is formed rather than a mononuclear coordination compound. [RhCl(Cp*)( 1 )]Cl and [IrCl(Cp*)( 1 )]Cl react with water regio‐ and diastereoselectively at the external P?C double bond, leading exclusively to the anti‐addition products [MCl(Cp*)( 1 H ? OH)]Cl as confirmed by X‐ray crystal‐structure determination. 相似文献
5.
Tuning the Excited State of Water‐Soluble IrIII‐Based DNA Intercalators that are Isostructural with [RuII(NN)2(dppz)] Light‐Switch Complexes 下载免费PDF全文
Sasha Stimpson Dan R. Jenkinson Andrew Sadler Dr. Mark Latham Dr Ashley Wragg Dr. Anthony J. H. M. Meijer Dr. Jim A. Thomas 《Angewandte Chemie (International ed. in English)》2015,54(10):3000-3003
The synthesis of two new IrIII complexes which are effectively isostructural with well‐established [Ru(NN)2(dppz)]2+ systems is reported (dppz=dipyridophenazine; NN=2,2′‐bipyridyl, or 1,10‐phenanthroline). One of these IrIII complexes is tricationic and has a conventional N6 coordination sphere. The second dicationic complex has a N5C coordination sphere, incorporating a cyclometalated analogue of the dppz ligand. Both complexes show good water solubility. Experimental and computational studies show that the photoexcited states of the two complexes are very different from each other and also differ from their RuII analogues. Both of the complexes bind to duplex DNA with affinities that are two orders of magnitude higher than previously reported Ir(dppz)‐based systems and are comparable with RuII(dppz) analogues. 相似文献
6.
Encapsulation and Enhanced Luminescence Properties of IrIII Complexes within a Hexameric Self‐Assembled Capsule 下载免费PDF全文
Dr. Shinnosuke Horiuchi Hirotaka Tanaka Prof. Dr. Eri Sakuda Prof. Dr. Yasuhiro Arikawa Prof. Dr. Keisuke Umakoshi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(49):17533-17537
Encapsulation and luminescence studies of [Ir(ppy)2(bpy)]Cl (ppy=2‐phenylpyridinate, bpy=2,2′‐bipyridine) within a hexameric resorcinarene capsule are reported. One IrIII complex cation was encapsulated within the capsule, as demonstrated by NMR and dynamic light scattering (DLS) studies. The emission color of the IrIII complex was drastically changed from orange to yellow by encapsulation, in contrast with the lack of significant changes in the absorption spectrum. The hexameric capsule effectively hampers the non‐radiative pathway to increase both the luminescence quantum yield and the exited state lifetime. The luminescent properties of the encapsulated IrIII complex depend on the ratio of IrIII complex to the resorcinarene monomer as well as the concentration of resorcinarene monomer owing to the reversible process of self‐assembly of the hexameric capsule. Quenching experiments revealed that the IrIII complex in the capsule was effectively separated from quenchers. 相似文献
7.
Tuning the Cellular Uptake Properties of Luminescent Heterobimetallic Iridium(III)–Ruthenium(II) DNA Imaging Probes 下载免费PDF全文
Dr. Ashley Wragg Dr. Martin R. Gill Dr. David Turton Harry Adams Thomas M. Roseveare Prof. Carl Smythe Dr. Xiaodi Su Dr. Jim A. Thomas 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(43):14004-14011
The synthesis of two new luminescent dinuclear IrIII–RuII complexes containing tetrapyrido[3,2‐a:2′,3′‐c:3′′,2′′‐h:2′′′,3′′′‐j]phenazine (tpphz) as the bridging ligand is reported. Unlike many other complexes incorporating cyclometalated IrIII moieties, these complexes display good water solubility, allowing the first cell‐based study on IrIII–RuII bioprobes to be carried out. Photophysical studies indicate that emission from each complex is from a RuII excited state and both complexes display significant in vitro DNA‐binding affinities. Cellular studies show that each complex is rapidly internalised by HeLa cells, in which they function as luminescent nuclear DNA‐imaging agents for confocal microscopy. Furthermore, the uptake and nuclear targeting properties of the complex incorporating cyclometalating 2‐(4‐fluorophenyl)pyridine ligands around its IrIII centre is enhanced in comparison to the non‐fluorinated analogue, indicating that fluorination may provide a route to promote cell uptake of transition‐metal bioprobes. 相似文献
8.
Steve Comby Floriana Stomeo Colin P. McCoy Thorfinnur Gunnlaugsson 《Helvetica chimica acta》2009,92(11):2461-2473
The synthesis of the C2‐symmetrical ligand 1 consisting of two naphthalene units connected to two pyridine‐2,6‐dicarboxamide moieties linked by a xylene spacer and the formation of LnIII‐based (Ln=Sm, Eu, Tb, and Lu) dimetallic helicates [Ln2? 1 3] in MeCN by means of a metal‐directed synthesis is described. By analyzing the metal‐induced changes in the absorption and the fluorescence of 1 , the formation of the helicates, and the presence of a second species [Ln2? 1 2] was confirmed by nonlinear‐regression analysis. While significant changes were observed in the photophysical properties of 1 , the most dramatic changes were observed in the metal‐centred lanthanide emissions, upon excitation of the naphthalene antennae. From the changes in the lanthanide emission, we were able to demonstrate that these helicates were formed in high yields (ca. 90% after the addition of 0.6 equiv. of LnIII), with high binding constants, which matched well with that determined from the changes in the absorption spectra. The formation of the LuIII helicate, [Lu2? 1 3], was also investigated for comparison purposes, as we were unable to obtain accurate binding constants from the changes in the fluorescence emission upon formation of [Sm2? 1 3], [Eu2? 1 3], and [Tb2? 1 3]. 相似文献
9.
Raphaël Tripier Marcel Hollenstein Mourad Elhabiri Anne‐Sophie Chauvin Gaël Zucchi Claude Piguet Jean‐ClaudeG. Bünzli 《Helvetica chimica acta》2002,85(7):1915-1929
Bis(2‐{6‐(diethylcarbamoyl)‐4‐[(4‐isothiocyanatophenyl)ethynyl]pyridin‐2′‐yl}‐1‐ethylbenzimidazol‐5‐yl)methane ( L G ) reacts with trivalent lanthanide ions in acetonitrile to yield triple‐stranded dimetallic helicates [Ln2( L G )3]6+. 1H‐NMR Data point to the helicates being the only species formed under stoichiometric conditions and having a time‐averaged D3 symmetry on the NMR time scale. The photophysical properties of L G and its helicates are discussed with respect to the closely related ligands L B , L E , and their complexes, two ligands devoid of the isothiocyanatophenylethynyl substituent. The quantum yield of the ligand fluorescence is three times smaller compared to L E , while that of the EuIII‐centered luminescence (1.1%) is three times larger. On the other hand, the luminescence of TbIII is not sensitized by L G . This is explained in terms of energy differences between the singlet and triplet states on one hand, and between the 0‐phonon transition of the triplet state and the excited metal ion states on the other. This work demonstrates that bulky substituents in the 4‐position of the pyridine ring do not prevent the formation of triple‐stranded helicates, opening the way for luminescent probes that can easily be coupled to biological materials. 相似文献
10.
Esra Altuntaş Andreas Winter Anja Baumgaertel Renzo M. Paulus Christoph Ulbricht Anna C. Crecelius Nikolaus Risch Ulrich S. Schubert 《Journal of mass spectrometry : JMS》2012,47(1):34-40
An electrospray ionization quadrupole time‐of‐flight mass spectrometer has been utilized to investigate the relative ligand‐binding strengths in a series of heteroleptic‐charged iridium(III) complexes of the general formula [(C^N)2IrIII(S‐tpy)](PF6) by using variable collision energies. Collision‐induced dissociation experiments were performed in order to study the stability of the IrIII complexes that are, for instance, suitable phosphors in light‐emitting electrochemical cells. The ratio of signal intensities belonging to the fragment and the undissociated complex depends on the collision energy applied for the tandem mass spectra (MS/MS) analysis. By defining the threshold collision energy and the point of complete complex dissociation, it is possible to estimate the relative complex stabilities depending on the nature of the coordinated ligands [i.e. type of cyclometalating ligand (C^N), substituents on the S‐shaped terpyridine (S‐tpy)]. The collision energy values differed as a function of the coordination sphere of the IrIII centers. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
11.
Ernesto Mesto Fernando Scordari Maria Lacalamita Luisa De Cola Roberta Ragni Gianluca Maria Farinola 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(5):480-482
The title complex, [Ir2(C18H13FNO2S)4Cl2]·C7H8, was crystallized from dichloromethane solution under a toluene atmosphere. It is a dimeric complex in which each of the two IrIII centres is octahedrally coordinated by two bridging chloride ligands and by two chelating cyclometalated 2‐(4‐benzylsulfonyl‐2‐fluorophenyl)pyridine ligands. The crystal structure analysis unequivocally establishes the trans disposition of the two cyclometalated ligands bound to each IrIII centre, contrary to our previous hypothesis of a cis disposition. The latter was based on the 1H NMR spectra of a series of dimeric benzylsulfonyl‐functionalized dichloride‐bridged iridium complexes, including the compound described in the present work [Ragni et al. (2009). Chem. Eur. J. 15 , 136–148]. The toluene solvent molecules, embedded in cavities in the crystal structure, are highly disordered and could not be modelled successfully; their contribution was removed from the refinement using the SQUEEZE routine in the program PLATON [Spek (2009). Acta Cryst. D 65 , 148–155]. 相似文献
12.
Iris de Krom Dr. Evgeny A. Pidko Dr. Martin Lutz Prof. Dr. Christian Müller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(23):7523-7531
RhIII and IrIII complexes based on the λ3‐P,N hybrid ligand 2‐(2′‐pyridyl)‐4,6‐diphenylphosphinine ( 1 ) react selectively at the P?C double bond to chiral coordination compounds of the type [( 1 H ? OH)Cp*MCl]Cl ( 2 , 3 ), which can be deprotonated with triethylamine to eliminate HCl. By using different bases, the pKa value of the P? OH group could be estimated. Whereas [( 1 H ? O)Cp*IrCl] ( 4 ) is formed quantitatively upon treatment with NEt3, the corresponding rhodium compound [( 1 H ? O)Cp*RhCl] ( 5 ) undergoes tautomerization upon formation of the λ5σ4‐phosphinine rhodium(III) complex [( 1? OH)Cp*RhCl] ( 6 ) as confirmed by single‐crystal X‐ray diffraction. Blocking the acidic P? OH functionality in 3 by introducing a P? OCH3 substituent leads directly to the λ5σ4‐phosphinine iridium(III) complex ( 8 ) upon elimination of HCl. These new transformations in the coordination environment of RhIII and IrIII provide an easy and general access to new transition‐metal complexes containing λ5σ4‐phosphinine ligands. 相似文献
13.
Vojtech Novohradsky Anna Rovira Cormac Hally Alex Galindo Gloria Vigueras Albert Gandioso Marie Svitelova Roger Bresolí‐Obach Hana Kostrhunova Lenka Markova Jana Kasparkova Santi Nonell Jos Ruiz Viktor Brabec Vicente Marchn 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(19):6377-6381
Although cyclometalated IrIII complexes have emerged as promising photosensitizers for photodynamic therapy, some key drawbacks still hamper clinical translation, such as operability in the phototherapeutic window and reactive oxygen species (ROS) production efficiency and selectivity. In this work, a cyclometalated IrIII complex conjugated to a far‐red‐emitting coumarin, IrIII–COUPY, is reported with highly favourable properties for cancer phototherapy. IrIII–COUPY was efficiently taken up by HeLa cells and showed no dark cytotoxicity and impressive photocytotoxicity indexes after irradiation with green and blue light, even under hypoxia. Importantly, a clear correlation between cell death and intracellular generation of superoxide anion radicals after visible light irradiation was demonstrated. This strategy opens the door to novel fluorescent photodynamic therapy agents with promising applications in theragnosis. 相似文献
14.
Triphenylamine‐Appended Half‐Sandwich Iridium(III) Complexes and Their Biological Applications 下载免费PDF全文
Xiangdong He Meng Tian Dr. Xicheng Liu Yanhua Tang Chang Fang Shao Peiwei Gong Jinfeng Liu Shumiao Zhang Lihua Guo Prof. Zhe Liu 《化学:亚洲杂志》2018,13(11):1500-1509
Organometallic half‐sandwich IrIII complexes of the type [(η5‐Cpx)Ir(N^N)Cl]PF6 (Cpx: Cp* or its phenyl Cpxph or biphenyl Cpxbiph derivatives; N^N: triphenylamine (TPA)‐substituted bipyridyl ligand groups) were synthesized and characterized. The complexes showed excellent bovine serum albumin (BSA) and DNA binding properties and were able to oxidize NADH to NAD+ (NAD=nicotinamide adenine dinucleotide) efficiently. The complexes induced apoptosis effectively and led to the emergence of reactive oxygen species (ROS) in cells. All complexes showed potent cytotoxicity with IC50 values ranging from 1.5 to 7.1 μm toward A549 human lung cancer cells after 24 hours of drug exposure, which is up to 14 times more potent than cisplatin under the same conditions. 相似文献
15.
Takanori Soya Prof. Dr. Atsuhiro Osuka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(30):10639-10644
The metalation of meso‐tetrakis(pentafluorophenyl)‐substituted [26]rubyrin has been explored with Group 9 metal salts (RhI, CoII, IrIII), affording a Hückel aromatic [26]rubyrin–bis‐RhI complex with a highly curved gable‐like structure, a Hückel antiaromatic [24]rubyrin–bis‐CoII complex that displays intramolecular antiferromagnetic coupling between the two CoII ions (J=?4.5 cm?1), and two Cp*‐capped IrIII complexes; in one, the iridium metal sits on the [26]rubyrin frame with two Ir?N bonds, whereas the other has an additional Ir?C bond, although both IrIII complexes display moderate aromatic character. This work demonstrates characteristic metalation abilities of this [26]rubyrin toward Group 9 metals. 相似文献
16.
Iridium(III) Complexes Bearing Pyrene‐Functionalized 1,10‐Phenanthroline Ligands as Highly Efficient Sensitizers for Triplet–Triplet Annihilation Upconversion 下载免费PDF全文
Yue Lu Junsi Wang Dr. Niamh McGoldrick Xiaoneng Cui Prof. Dr. Jianzhang Zhao Colin Caverly Dr. Brendan Twamley Dr. Gearoid M. Ó Máille Bryan Irwin Robert Conway‐Kenny Prof. Dr. Sylvia M. Draper 《Angewandte Chemie (International ed. in English)》2016,55(47):14688-14692
“Chemistry‐on‐the‐complex” synthetic methods have allowed the selective addition of 1‐ethynylpyrene appendages to the 3‐, 5‐, 3,8‐ and 5,6‐positions of IrIII‐coordinated 1,10‐phenanthroline via Sonogashira cross‐coupling. The resulting suite of complexes has given rise to the first rationalization of their absorption and emission properties as a function of the number and position of the pyrene moieties. Strong absorption in the visible region (e.g. 3,8‐substituted Ir‐3 : λabs=481 nm, ?=52 400 m ?1 cm?1) and long‐lived triplet excited states (e.g. 5‐substituted Ir‐2 : τT=367.7 μs) were observed for the complexes in deaerated CH2Cl2. On testing the series as triplet sensitizers for triplet–triplet annihilation upconversion, those IrIII complexes bearing pyrenyl appendages at the 3‐ and 3,8‐positions ( Ir‐1 , Ir‐3 ) were found to give optimal upconversion quantum yields (30.2 % and 31.6 % respectively). 相似文献
17.
Emmanuel Deiters Dr. Bo Song Dr. Anne‐Sophie Chauvin Dr. Caroline D. B. Vandevyver Dr. Frédéric Gumy Jean‐Claude G. Bünzli Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(4):885-900
A series of homoditopic ligands H2LCX (X=4–6) has been designed to self‐assemble with lanthanide ions (LnIII), resulting in neutral bimetallic helicates of overall composition [Ln2(LCX)3] with the aim of testing the influence of substituents on the photophysical properties, particularly the excitation wavelength. The complex species are thermodynamically stable in water (log β23 in the range 26–28 at pH 7.4) and display a metal‐ion environment with pseudo‐D3 symmetry and devoid of coordinated water molecules. The emission of EuIII, TbIII, and YbIII is sensitised to various extents, depending on the properties of the ligand donor levels. The best helicate is [Eu2(LC5)3] with excitation maxima at 350 and 365 nm and a quantum yield of 9 %. The viability of cervix cancer HeLa cells is unaffected when incubated with up to 500 μm of the chelate during 24 h. The helicate permeates into the cells by endocytosis and locates into lysosomes, which co‐localise with the endoplasmatic reticulum, as demonstrated by counterstaining experiments. The relatively long excitation wavelength allows easy recording of bright luminescent images on a confocal microscope (λexc=405 nm). The new lanthanide bioprobe remains undissociated in the cell medium, and is amenable to facile derivatisation. Examination of data for seven EuIII and TbIII bimetallic helicates point to shortcomings in the phenomenological rules of thumb between the energy gap ΔE(3ππ*–5DJ) and the sensitisation efficiency of the ligands. 相似文献
18.
Iron(II) Supramolecular Helicates Condense Plasmid DNA and Inhibit Vital DNA‐Related Enzymatic Activities 下载免费PDF全文
Dr. Jaroslav Malina Prof. Michael J. Hannon Prof. Dr. Viktor Brabec 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(31):11189-11195
The dinuclear iron(II) supramolecular helicates [Fe2L3]Cl4 (L=C25H20N4) bind to DNA through noncovalent (i.e., hydrogen‐bonding, electrostatic) interactions and exhibit antimicrobial and anticancer effects. In this study, we show that the helicates condense plasmid DNA with a much higher potency than conventional DNA‐condensing agents. Notably, molecules of DNA in the presence of the M enantiomer of [Fe2L3]Cl4 do not form intermolecular aggregates typically formed by other condensing agents, such as spermidine or spermine. The helicates inhibit the activity of several DNA‐processing enzymes, such as RNA polymerase, DNA topoisomerase I, deoxyribonuclease I, and site‐specific restriction endonucleases. However, the results also indicate that the DNA condensation induced by the helicates does not play a crucial role in these inhibition reactions. The mechanisms for the inhibitory effects of [Fe2L3]Cl4 helicates on DNA‐related enzymatic activities have been proposed. 相似文献
19.
Xiaofei Chen Christian Mevissen Saskia Huda Christian Gb Iris M. Oppel Markus Albrecht 《Angewandte Chemie (International ed. in English)》2019,58(37):12879-12882
Two biscatecholester ligands with oligoether spacers were used to prepare dinuclear titanium(IV) triscatecholate based helicates. In the case of Li4[( 1 / 2 )3Ti2], “classical” helicates with three internally bound Li+ ions and syn‐oriented ligands in the complex units (fac/fac isomer) were obtained. In the case of the sodium salt Na4[( 2 )3Ti2], a different homochiral dinuclear triple‐stranded helicate with two internally bound Na+ ions was formed. The complex units are anti‐configured, and two of the ligand spacers are connecting internal with external positions of the helicate (mer/mer isomer). Removal of the sodium ions and addition of lithium ions leads to the switching from one topology to the other with an expanded helicate [( 2 )3Ti2]4? as an intermediate. Switching back to the “non‐classical” helicate cannot be observed because severe structural rearrangements would be required. 相似文献
20.
Bipyrimidines have been chosen as (N∧N)(N∧N) bridging ligands for connecting metal centers. IrIII-LnIII (Ln = Nd, Yb, Er) bimetallic complexes [Ir(dfppy)2(μ-bpm)Ln(TTA)3]Cl were synthesized by using Ir(dfppy)2(bpm)Cl as the ligand coordinating to lanthanide complexes Ln(TTA)3·2H2O. The stability constants between Ir(dfppy)2(bpm)Cl and lanthanide ions were measured by fluorescence titration. The obvious quenching of visible emission from IrIII complex in the IrIII-LnIII (Ln = Nd, Yb, Er) bimetallic complexes indicates that energy transfer occurred from IrIII center to lanthanides. NIR emissions from NdIII, YbIII, and ErIII were obtained under the excitation of visible light by selective excitation of the IrIII-based chromophore. It was proven that Ir(dfppy)2(bpm)Cl as the ligand could effectively sensitize NIR emission from NdIII, YbIII, and ErIII. 相似文献