74918-94-8Relevant academic research and scientific papers
Facile synthesis of new divergent imidazole-containing ligands for a 1-D cobalt(II) coordination polymer
Liu,Xiong, Hangxing,Li, Li,Yang, Chengxiong,Yin, Zhiwei,Chang, Anthony,Manke, David R.,Golen, James A.,Zhang, Guoqi
, p. 355 - 360 (2017)
A new divergent ligand (3a) containing a triaryl core and two imidazole side-arms has been designed and synthesized. The synthetic procedure utilizes a two-step strategy, i.e. the Kr?hnke condensation, followed by a Cu-catalyzed Ullman-type coupling. This synthetic strategy allows the facile introduction of various substituents on the 4-position of the central pyridine in the ligands, which was proved by the synthesis of a ligand analog (3b). The new ligands were well characterized by spectroscopic methods and X-ray structural analysis was carried out for 3a. Reaction of 3a with Co(NCS)2 by a layering method afforded single crystals of a coordination polymer 5, which was structurally characterized by X-ray diffraction. 5 is composed of two ligands and one Co(NCS)2 in its asymmetric unit and features a 1-D coordination polymer with nano-scale metallomacrocyles. The structure of 5 is found to be quite different from all known coordination networks composed of Co(NCS)2 and closely related divergent ligands.
Synthesis and characterization of novel phosphorescent host materials based on triphenylpyridine derivatives
Zhang, Xu,Ye, Qingqing,Fan, Yingtao,Hu, Xiaoyu,Shen, Yingzhong
, p. 2145 - 2152 (2020)
Three novel phosphorescent host materials, 4′,4?-(4-phenylpyridine-2,6-diyl)bis(N,N-diphenyl-[1,1′-biphenyl]-4-amine) (P1), 2,6-bis(4′-(naphthalen-1-yl)-[1,1′-biphenyl]-4-yl)-4-phenylpyridine (P2), and 2,6-bis(3′,5′-dimethyl-[1,1′-biphenyl]-4-yl)-4-phenylpyridine (P3), based on triphenylpyridine with a symmetrical molecular conformation were designed and synthesized from 2,6-bis(4-bromophenyl)-4-phenylpyridine (3) reacting with [4-(diphenylamino)phenyl]boronic acid (A1), [4-(naphthalen-1-yl)phenyl]boronic acid (A2), and (3,5-dimethylphenyl)boronic acid (A3) through Suzuki coupling reaction, respectively. The compounds obtained were characterized by elemental analysis, 1H NMR, and 13C NMR spectroscopy. The thermal properties of these materials were studied by thermogravimetric analysis and differential scanning calorimetry measurements, which showed that they exhibited excellent thermal stability with glass transition temperatures over 94?°C. Their photophysical properties were also investigated, and the results indicated that all compounds possessed considerably high triplet energy level greater than 2.6?eV; they also emitted blue fluorescence in different solvents. Finally, the results of the density function theory calculations revealed that the compound P1 showed the well-separated frontier molecular orbital, which indicated that it possessed bipolar carrier transport ability for holes and electrons, whereas the compound P2 and P3 exhibited greater overlap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital.
Synthesis of Kr?hnke pyridines through iron-catalyzed oxidative condensation/double alkynylation/amination cascade strategy
Gopalaiah, Kovuru,Choudhary, Renu
supporting information, (2021/09/15)
An efficient protocol for the synthesis of symmetrical and unsymmetrical 2,4,6-trisubstituted pyridines via oxidative cascade annulation of arylacetylenes with benzylamines has been developed. The reaction proceeds smoothly utilizing iron(II) triflate as a catalyst and molecular oxygen as an oxidant with broad substrate scope. Mechanistic studies reveal that the reaction may be experiences an oxidative condensation followed by double alkynylation and amination process.
Convenient one-pot synthesis of 1,2,4-oxadiazoles and 2,4,6-triarylpyridines using graphene oxide (GO) as a metal-free catalyst: Importance of dual catalytic activity
Basak, Puja,Dey, Sourav,Ghosh, Pranab
, p. 32106 - 32118 (2021/12/02)
A convenient and efficient process for the synthesis of 3,5-disubstituted 1,2,4-oxadiazoles and 2,4,6-triarylpyridines has been described using an inexpensive, environmentally benign, metal-free heterogeneous carbocatalyst, graphene oxide (GO). GO plays a dual role of an oxidizing agent and solid acid catalyst for synthesizing 1,2,4-oxadiazoles and triarylpyridines. This dual catalytic activity of GO is due to the presence of oxygenated functional groups which are distributed on the nanosheets of graphene oxide. A broad scope of substrate applicability and good sustainability is offered in this developed protocol. The results of a few control experiments reveal a plausible mechanism and the role of GO as a catalyst was confirmed by FTIR, XRD, SEM, and HR-TEM analysis.
Cyclometalated pt complexes of cnc pincer ligands: Luminescence and cytotoxic evaluation
Garbe, Simon,Krause, Maren,Klimpel, Annika,Neundorf, Ines,Lippmann, Petra,Ott, Ingo,Brünink, Dana,Strassert, Cristian A.,Doltsinis, Nikos L.,Klein, Axel
supporting information, p. 746 - 756 (2020/03/30)
In the framework of our attempts to develop cyclometalated Pt(II) complexes toward bifunctional targeting inhibitors or agents for photodynamic therapy, diagnostics, and bioimaging, a series of bis-cyclometalated Pt(II) complexes [Pt(CNC)(L)] (L = DMSO, MeCN) containing various (CNC)2- ligands based on 2,6-diphenylpyridine were synthesized and characterized analytically and spectroscopically, focusing on their electrochemical, luminescence, and antiproliferative properties. Electrochemical experiments and UV-vis absorption spectroscopy suggest ligand-centered LUMOs and metal-centered HOMOs in line with DFT calculations. Extension of the ancillary phenyl to naphthyl cores and a central 4-phenylpyridine group instead of pyridine results in bathochromic shifts of the long-wavelength absorption bands ranging from 420 to 440 nm, with the latter shift being more pronounced. The complexes of the fused CNC heterocyclic systems dba (H2dba = dibenzo[c,h]acridine), db(ph)a (H2db(ph)a = 7-phenyldibenzo[c,h]acridine), and bzqph (HbzqphH = 2-phenylbenzo[h]quinoline) absorb far more red-shifted in the range 500-530 nm. All complexes show reversible first electrochemical reductions and irreversible oxidations with an electrochemical gap of about 3 V, roughly in line with the absorption energies. While the 2,6-diphenylpyridine complexes [Pt(CNC)(DMSO)] show no luminescence at ambient temperature in solution, the fused dba, db(ph)a, and bzqph derivatives are efficient triplet emitters at ambient temperature with emission wavelengths in the region 575-600 nm and quantum yields ranging from 7 to 23%. Vibrationally resolved emission spectra calculated in the framework of DFT faithfully reproduce the experimental data. TD-DFT calculations at the excited-state T1 geometry reveal intraligand π-π*/MLCT character of the emission for all three investigated complexes. Antiproliferative tests on selected complexes gave very different toxicities, ranging from lower than 1 μM to virtually nontoxic. The data allowed drawing some structure-activity relationships (SAR), even though variations in solubility could also significantly account for the different toxicities.
A New Synthetic Pathway to Triphenylpyridines via Cascade Reactions Utilizing a New Iron-Organic Framework as a Recyclable Heterogeneous Catalyst
Doan, Son H.,Tran, Nhu K. Q.,Pham, Phuc H.,Nguyen, Vu H. H.,Nguyen, Ngoc N.,Ha, Phuong T. M.,Li, Shuang,Le, Ha V.,Le, Nhan T. H.,Tu, Thach N.,Phan, Nam T. S.
supporting information, p. 2382 - 2389 (2019/03/27)
A new iron-organic framework, VNU-22 {[Fe3(BTC)(BPDC)2]·11.97H2O}, constructed from BTC3–, BPDC2– pillars and infinite [Fe3(CO2)7]∞ rod SBU, was obtained. The VNU-22 was utilized as a heterogeneous catalyst in the synthesis of 2,4,6-triphenylpyridines via cascade reactions from acetophenones and phenylacetic acids with ammonium acetate as a nitrogen source. This transformation is new. The VNU-22 was more active in the cascade reactions than many homogeneous and heterogeneous catalysts. The framework catalyst was recovered and reutilized without an appreciable decline in its performance. To our best knowledge, this synthetic pathway to 2,4,6-triphenylpyridines was not previously reported, and would attract interests from the chemical industry.
Synthesis of triphenylpyridines: Via an oxidative cyclization reaction using Sr-doped LaCoO3 perovskite as a recyclable heterogeneous catalyst
Le, Thu N. M.,Doan, Son H.,Pham, Phuc H.,Trinh, Khang H.,Huynh, Tien V.,Tran, Tien T. T.,Le, Minh-Vien,Nguyen, Tung T.,Phan, Nam T. S.
, p. 23876 - 23887 (2019/08/12)
An La0.6Sr0.4CoO3 strontium-doped lanthanum cobaltite perovskite was prepared via a gelation and calcination approach and used as a heterogeneous catalyst for the synthesis of triphenylpyridines via the cyclization reactio
A Facile and Green Synthesis of 2,4,6-Triarylpyridine Derivatives Using the Modified Mesoporous Organic Polymer Based on Calix [4]Resorcinarene: As an Efficient and Reusable Heterogeneous Acidic Catalyst
Mouradzadegun,Mostafavi,Ganjali
, p. 187 - 195 (2019/05/27)
Abstract: The work describes an efficient one-pot synthesis of 2,4,6-trisubstituted pyridine derivatives through a three-component catalytic reaction. The procedure involves mesoporous organic polymer based on calix[4]resorcinarene in and functionalized b
A new route to triphenylpyridines utilizing ketoximes as building blocks via cascade reactions under iron-organic framework catalysis
Nguyen, Vu H.H.,Doan, Son H.,Van, Tram T.,Pham, Phuc H.,Nguyen, Tran T.N.,Nguyen, Ngoc N.,Tu, Thach N.,Phan, Nam T.S.
, (2019/02/25)
Iron-based metal–organic framework VNU-20 was utilized as a heterogeneous catalyst for cascade reactions between ketoximes and dibenzyl ether to produce 2,4,6-triphenylpyridines. Additionally, benzyl alcohol and (dimethoxymethyl)benzene could be used as an alternative starting materials for the transformation. The oxidant exhibited a remarkable impact on the reactions, and di-tert-butylperoxide was the most appropriate candidate. The VNU-20 displayed higher efficiency than many homogeneous and heterogeneous catalysts. The catalyst was reusable for the cascade reactions without a noticeable deterioration in catalytic activity. This transformation is new, and would offer alternative routes to triphenylpyridines utilizing ketoximes as building blocks.
An efficient one pot three-component synthesis of 2,4,6-triarylpyridines using triflimide as a metal-free catalyst under solvent-free conditions
Wang, Hongshe,Zhao, Weixing,Du, Juan,Wei, Fenyan,Chen, Qi,Wang, Xiaomei
, p. 5158 - 5163 (2019/02/27)
A simple and efficient protocol developed for one pot three-component synthesis of 2,4,6-triarylpyridines from aromatic aldehydes, substituted acetophenones and ammonium acetate using the versatile super Br?nsted acid triflimide (HNTf2) as an effective catalyst is described. The reactions proceed well in the presence of 1 mol% of HNTf2 at 80 °c under solvent-free conditions and provide the corresponding triarylpyridines in good to excellent yields. The method reported has several advantages such as a metal-free and commercially available catalyst, mild reaction conditions and lower loading of catalyst.
