613-32-1Relevant articles and documents
NIR organic dyes based on phenazine-cyanine for photoacoustic imaging-guided photothermal therapy
Yan, Yongchao,Chen, Jiawen,Yang, Zhijuan,Zhang, Xiao,Liu, Zhuang,Hua, Jianli
, p. 7420 - 7426 (2018)
As non-invasive diagnosis and therapy methods, photoacoustic (PA) imaging and photothermal therapy (PTT) have attracted extensive attention. Herein, two new acceptor-donor-acceptor near-infrared organic phenazine-cyanine dyes PH-1 and PH-2 were reported for photoacoustic imaging-guided photodynamic therapy. In the strong donor phenazine molecule, the electron-withdrawing indole salt unit was introduced for absorption to the near-infrared region. To improve water solubility, the two organic dyes were assembled with human serum albumin (HSA) to form nanoparticles of appropriate sizes, i.e., PH-1@HSA and PH-2@HSA, which showed excellent stability in both weakly acidic and weakly basic environments. Moreover, the results showed that PH-1@HSA and PH-2@HSA nanoparticles can effectively transform luminous energy to thermal energy in vitro and in vivo, and they can be utilized for PA imaging. Importantly, PH-1@HSA can accumulate in mice subcutaneous tumors by enhanced permeability and retention (EPR) and damage cancer tissues effectively.
Highly efficient green organic light emitting diodes with phenanthroimidazole-based thermally activated delayed fluorescence emitters
Huang, Zhi,Xiang, Songpo,Zhang, Qing,Lv, Xialei,Ye, Shaofeng,Guo, Runda,Wang, Lei
, p. 2379 - 2386 (2018)
Here, a phenanthroimidazole moiety was firstly introduced into the construction of thermally activated delayed fluorescence (TADF) emitters, and two novel TADF emitters consisting of phenanthroimidazole as the acceptor group and phenazine as the donor group, 1-(4-(tert-butyl)phenyl)-2-(4-(10-phenylphenazin-5(10H)-yl)phenyl)-1H-phenanthro[9,10-d]imidazole (PPZTPI) and 1-phenyl-2-(4-(10-phenylphenazin-5(10H)-yl)phenyl)-1H-phenanthro[9,10-d]imidazole (PPZPPI) were designed and synthesized. The highly twisted conformation between phenazine and phenanthroimidazole in the molecules results in effective spatial separation of the HOMO and LUMO and small singlet-triplet splittings. Both compounds possess obvious TADF features. Their crystallographic properties, electronic structures, thermal stabilities, photophysical properties, and energy levels are studied systematically. Organic light-emitting diodes (OLEDs) using these two green TADF emitters demonstrate high external quantum efficiencies of 21.06% for PPZPPI and 20.52% for PPZTPI, respectively, which is comparable to most of the previously reported TADF OLEDs.
Singlet and Triplet Contributions to the Excited-State Activities of Dihydrophenazine, Phenoxazine, and Phenothiazine Organocatalysts Used in Atom Transfer Radical Polymerization
Bhattacherjee, Aditi,Sneha, Mahima,Lewis-Borrell, Luke,Amoruso, Giordano,Oliver, Thomas A.A.,Tyler, Jasper,Clark, Ian P.,Orr-Ewing, Andrew J.
, p. 3613 - 3627 (2021)
The photochemical dynamics of three classes of organic photoredox catalysts employed in organocatalyzed atom-transfer radical polymerization (O-ATRP) are studied using time-resolved optical transient absorption and fluorescence spectroscopy. The nine catalysts selected for study are examples of N-aryl and core-substituted dihydrophenazine, phenoxazine and phenothiazine compounds with varying propensities for control of polymerization outcomes. Excited singlet-state lifetimes extracted from the spectroscopic measurements are reported in N,N-dimethylformamide (DMF), dichloromethane (DCM), and toluene. Ultrafast (200 fs to 3 ps) electronic relaxation of the photocatalysts after photoexcitation at near-UV wavelengths (318-390 nm) populates the first singlet excited state (S1). The S1-state lifetimes range from 130 ps to 40 ns with a considerable dependence on the photocatalyst structure and the solvent. The competition between ground electronic state recovery and intersystem crossing controls triplet state populations and is a minor pathway in the dihydrophenazine derivatives but is of greater importance for phenoxazine and phenothiazine catalysts. A comparison of our results with previously reported O-ATRP performances of the various photoredox catalysts shows that high triplet-state quantum yields are not a prerequisite for controlling polymer dispersity. For example, the photocatalyst 5,10-bis(4-cyanophenyl)-5,10-dihydrophenazine, shown previously to exert good polymerization control, possesses the shortest S1-state lifetime (135 ps in DMF and 180 ps in N,N-dimethylacetamide) among the nine examples reported here and a negligible triplet-state quantum yield. The results call for a re-evaluation of the excited-state properties of most significance in governing the photocatalytic behavior of organic photoredox catalysts in O-ATRP reactions.
Formation of 5,10-dihydrophenazine from phenazine by Pseudomonas cepacia IFO 15124 at low oxygen tensions
Kawashima, Hideki,Ogawa, Satoshi
, p. 1186 - 1187 (1996)
5,10-Dihydrophenazine (H2Phen) was formed from phenazine (Phen) by Pseudomonas cepacia IFO 15124 in growing cultures at low oxygen tensions. Effects of culture conditions on microbial reduction of Phen with this strain were investigated. Under optimized conditions, the transformation of Phen to H2Phen by this strain gave the molar conversion yield of 30%. However, H2Phen was not detected in the culture medium when the strain was incubated with Phen with sufficient aeration.
Cross-linking Effects on Performance Metrics of Phenazine-Based Polymer Cathodes
Gannett, Cara N.,Peterson, Brian M.,Shen, Luxi,Seok, Jeesoo,Fors, Brett P.,Abru?a, Héctor D.
, p. 2428 - 2435 (2020)
Developing cathodes that can support high charge–discharge rates would improve the power density of lithium-ion batteries. Herein, the development of high-power cathodes without sacrificing energy density is reported. N,N′-diphenylphenazine was identified as a promising charge-storage center by electrochemical studies due to its reversible, fast electron transfer at high potentials. By incorporating the phenazine redox units in a cross-linked network, a high-capacity (223 mA h g?1), high-voltage (3.45 V vs. Li/Li+) cathode material was achieved. Optimized cross-linked materials are able to deliver reversible capacities as high as 220 mA h g?1 at 120 C with minimal degradation over 1000 cycles. The work presented herein highlights the fast ionic transport and rate capabilities of amorphous organic materials and demonstrates their potential as materials with high energy and power density for next-generation electrical energy-storage technologies.
A robust phenazine-containing organic polymer as catalyst for amine oxidative coupling reactions
Guo, Zhiyong,Lin, Junyu,Zhan, Hongbing
, p. 338 - 344 (2020)
Here we present the design and synthesis of a new robust microporous organic polymer (TPBP) decorated with phenazine groups which endowed reversibly redox-active properties. The obtained TPBP possesses relatively high surface area (359 m2/g) and good thermal stability. TPBP exhibits excellent catalytic capability for the oxidative homocoupling of amines with high activity and selectivity toward target products. Besides, this metal-free catalyst demonstrated excellent recyclability after 6 cycles under the investigated conditions. By means of EPR and UV-vis spectroscopy, a plausible mechanism of the amine oxidative coupling reaction was deduced via a single electron transfer from TPBP radical cations to amine substrates.
Dihydrophenazine linked porous organic polymers for high capacitance and energy density pseudocapacitive electrodes and devices
Zhang, Huanhuan,Tang, Xiaohui,Gu, Cheng
, p. 4984 - 4989 (2021)
Redox porous organic polymers are promising pseudocapacitive materials. However, their specific capacitance still needs further elevation. Herein, we report a novel dihydrophenazine derived porous organic polymer, GT-POP-1. The GT-POP-1 based electrode and asymmetric device show high specific capacitance and energy density metrics of 97.1 mF cm?2and 7.3 μW h cm?2
Controlled emission colors and singlet-triplet energy gaps of dihydrophenazine-based thermally activated delayed fluorescence emitters
Lee, Jiyoung,Shizu, Katsuyuki,Tanaka, Hiroyuki,Nakanotani, Hajime,Yasuda, Takuma,Kaji, Hironori,Adachi, Chihaya
, p. 2175 - 2181 (2015)
We have developed thermally activated delayed fluorescence (TADF) emitters containing 5,10-dihydrophenazine as an electron donor and various electron-acceptor units. The TADF emitters exhibit wide ranges of emission colors from green to orange, singlet-triplet energy gaps ΔEST of ～0-0.19 eV, and delayed fluorescence lifetimes τd of 0.1-50 μs. An organic light-emitting diode containing one of the TADF emitters exhibits a maximum external quantum efficiency (EQE) of 12%, which is higher than those obtained with conventional fluorescent emitters. Time-resolved photoluminescence measurements of the compounds in a host matrix reveal that TADF makes a large contribution to the EQE of the devices. Our findings provide guidelines for modulating ΔEST and τd of TADF emitters.
Dihydrophenazine-based double-anchoring dye for dye-sensitized solar cells
Kumar, Dhirendra,Chen, Yu-Lin,Tsai, Chih-Hung,Wong, Ken-Tsung
, p. 361 - 369 (2020)
A novel dihydrophenazine-based organic di-anchoring dye DK-11 was synthesized by utilizing a simple synthetic protocol. The dye was characterized by optical and electrochemical studies and used as a sensitizer for dye-sensitized solar cell. The proposed butterfly structure was supported by IR experiments which ensured the binding of both carboxylic acid units on the semiconductor surface. Using the dye DK-11, the device generated an efficiency of 5.07% with JSC, VOC, and FF values of 10.65 mA/cm2, 0.67 V, and 0.71, respectively.
Post-Synthetic Modification of Metal-Organic Frameworks Bearing Phenazine Radical Cations for aza-Diels-Alder Reactions
Jiang, Wei-Ling,Huang, Bin,Wu, Meng-Xiang,Zhu, Ye-Kai,Zhao, Xiao-Li,Shi, Xueliang,Yang, Hai-Bo
supporting information, p. 3985 - 3992 (2021/11/01)
Metal-organic frameworks (MOFs) consisting of organic radicals are of great interest because they have exhibited unique and intriguing optical, electronic, magnetic, and chemo-catalytic properties, and thus have demonstrated great potential applications in optical, electronic, and magnetic devices, and as catalysts. However, the preparation of MOFs bearing stable organic radicals is very challenging because most organic radicals are highly reactive and difficult to incorporate into the framework of MOFs. Herein we reported a post-synthetic modification strategy to prepare a novel MOF containing phenazine radical cations, which was used as heterogeneous catalyst for aza-Diels-Alder reaction. The zinc-based metal-organic framework Zn2(PHZ)2(dabco) (N) was successfully synthesized from 5,10-di(4-benzoic acid)-5,10-dihydrophenazine (PHZ), triethylene diamine (dabco) with Zn(NO3)2 ? 6H2O by solvothermal method. The as-synthesized MOF N was partially oxidized by AgSbF6 to form MOF R containing ～10% phenazine radical cation species. The resultant MOF R was found to keep the original crystal type of N and very persistent under ambient conditions. Consequently, MOF R was successfully employed in radical cation-catalyzed aza-Diels-Alder reactions with various imine substrates at room temperature with high reaction conversion. Moreover, heterogeneous catalyst MOF R was reusable up to five times without much loss of catalytic activity, demonstrating its excellent stability and recyclability. Therefore, the post-synthetic modification developed in this work is expected to become a versatile strategy to prepare radical-based MOFs for the application of heterogeneous catalysts in organic synthesis.
