602-55-1Relevant academic research and scientific papers
CeO2/Pd Nanoparticles Incorporated Fly Ash Zeolite: An Efficient and Recyclable Catalyst for Csp2-Csp2 Bond Formation Reactions
Sheeba Thavamani, Seth,Sudharsan, Murugesan,Santhana Mariya, Anitha,Suresh, Devarajan,Jose Amali, Arlin,Rajeswari, Sanniyasi,Peter Amaladhas, Thomas
, (2020)
The catalytic activity of CeO2 and palladium nanoparticles supported fly ash zeolite (CeO2/Pd@FAZ) for Csp2-Csp2 bond formation was studied. CeO2/Pd@FAZ was characterized by FTIR, XRD, EDAX and TEM studies. In the Suzuki-Miyauracross-coupling reaction, biphenyl derivatives with excellent yields were obtained, and the reaction conditions were optimized. The catalytic activity was explored using a wide variety of diversely substituted aryl bromides and chlorides with aryl boronic acid under optimized reaction conditions. The recyclability of the catalyst was established for three cycles, with the conversion rate from 99 to 40percent, which gained the advantage of heterogeneous catalysis.
Suzuki-Miyaura Micellar One-Pot Synthesis of Symmetrical and Unsymmetrical 4,7-Diaryl-5,6-difluoro-2,1,3-benzothiadiazole Luminescent Derivatives in Water and under Air
Sanzone, Alessandro,Calascibetta, Adiel,Ghiglietti, Erika,Ceriani, Chiara,Mattioli, Giuseppe,Mattiello, Sara,Sassi, Mauro,Beverina, Luca
, p. 15029 - 15042 (2018)
The Suzuki-Miyaura cross-coupling reaction of 4,7-dibromo-5,6-difluoro-2,1,3-benzothiadiazole with different arylboronic acids can be efficiently carried out in water and under air by means of micellar coupling. The careful tuning of reaction conditions enables preparation of symmetrically and unsymmetrically substituted derivatives. The moderate to good yields obtained, along with the wide variety of available substitution patterns, makes this sustainable methodology very useful for the preparation of building blocks for luminescent optoelectronic materials.
Palladium and nickel catalysed Suzuki cross-coupling of sterically hindered aryl bromides with phenylboronic acid
Griffiths, Clare,Leadbeater, Nicholas E.
, p. 2487 - 2490 (2000)
Nickel and palladium catalysts for the Suzuki cross-coupling of aryl halides bearing two ortho substituents with phenylboronic acid have been developed and used for the synthesis of sterically hindered biaryls. (C) 2000 Elsevier Science Ltd.
Amine-Tagged Fragmented Ligand Installation for Covalent Modification of MOF-74
Lim, Jaewoong,Lee, Seonghwan,Ha, Hyeonbin,Seong, Junmo,Jeong, Seok,Kim, Min,Baek, Seung Bin,Lah, Myoung Soo
, p. 9296 - 9300 (2021)
MOF-74 is one of the most explored metal–organic frameworks (MOFs), but its functionalization is limited to the dative post-synthetic modification (PSM) of the monodentate solvent site. Owing to the nature of the organic ligand and framework structure of MOF-74, the covalent PSM of MOF-74 is very demanding. Herein, we report, for the first time, the covalent PSM of amine-tagged defective Ni-MOF-74, which is prepared by de novo solvothermal synthesis by using aminosalicylic acid as a functionalized fragmented organic ligand. The covalent PSM of the amino group generates metal binding sites, and subsequent post-synthetic metalation with PdII ions affords the PdII-incorporated Ni-MOF-74 catalyst. This catalyst exhibits highly efficient, size-selective, and recyclable catalytic activity for the Suzuki–Miyaura cross-coupling reaction. This strategy is also useful for the covalent modification of amine-tagged defective Ni2(DOBPDC), an expanded analogue of MOF-74.
Imidazolin-2-ylidenaminophosphines as Highly Electron-Rich Ligands for Transition-Metal Catalysts
Wünsche, Marius A.,Mehlmann, Paul,Witteler, Tim,Buss, Florenz,Rathmann, Patrick,Dielmann, Fabian
, p. 11857 - 11860 (2015)
A variety of chemical transformations benefit from the use of strong electron-donating ancillary ligands, such as alkylphosphines or N-heterocyclic carbenes when electron-rich metal centers are required. Herein, we describe a facile and highly modular access to monodentate and bidentate imidazolin-2-ylidenamino-substituted phosphines. Evaluation of the phosphine's electronic properties substantiate that the formal replacement of alkyl or aryl groups by imidazolin-2-ylidenamino groups dramatically enhance their donor ability beyond that of alkylphosphines and even N-heterocyclic carbenes. The new phosphines have been coordinated onto palladium(II) centers, and the beneficial effect of the novel substitution patterns has been explored by using the corresponding complexes in the palladium-catalyzed Suzuki-Miyaura cross-coupling reaction of non-activated aryl chloride substrates. Upgrading phosphines: A conceptually new approach to a family of extremely electron-rich phosphines is based on the use of imidazolin-2-ylidenamino groups directly attached to the phosphorus atom. The steric and electronic properties of the new ligands can be easily varied owing to the general and modular synthesis, which provides new prospects for phosphine ligands in catalysis.
A colorimetric chemodosimeter for Pd(II): a method for detecting residual palladium in cross-coupling reactions
Houk, Ronald J.T.,Wallace, Karl J.,Hewage, Himali S.,Anslyn, Eric V.
, p. 8271 - 8278 (2008)
A colorimetric chemodosimeter (SQ1) for the detection of trace palladium salts in cross-coupling reactions mediated by palladium is described. Decolorization of SQ1 is affected by nucleophilic attack of ethanethiol in basic DMSO solutions. Thiol addition is determined to have an equilibrium constant (Keq) of 2.9×106 M-1, with a large entropic and modest enthalpic driving force. This unusual result is attributed to solvent effects arising from a strong coordinative interaction between DMSO and the parent squaraine. Palladium detection is achieved through thiol scavenging from the SQ1-ethanethiol complex leading to a color 'turn-on' of the parent squaraine. It was found that untreated samples obtained directly from Suzuki couplings showed no response to the assay. However, treatment of the samples with aqueous nitric acid generates a uniform Pd(NO3)2 species, which gives an appropriate response. 'Naked-eye' detection of Pd(NO3)2 was estimated to be as low as 0.5 ppm in solution and instrument-based detection was tested as low as 100 ppb. The average error over the working range of the assay was determined to be 7%.
Sterically enhanced 2-iminopyridylpalladium chlorides as recyclable ppm-palladium catalyst for Suzuki–Miyaura coupling in aqueous solution
Liang, Tongling,Lin, Wenhua,Ma, Yanping,Sun, Wen-Hua,Zhang, Liping
, (2021/10/20)
Sterically hindered 2-iminopyridine derivatives and their palladium chlorides complexes are designed and prepared, which efficiently promote the Suzuki–Miyaura coupling (SMC) reaction in aqueous solution. Besides the good to excellent yields and broad substrate scope, these catalysts can be reused for at least four new batches of the substrates. Spontaneous separation of coupling products in the aqueous reaction medium is the additional striking feature of this catalytic process. Furthermore, catalytic performance of palladium complexes bearing the azo-bridged phenyl groups was greatly influenced by the UV irradiation due to the cis/trans photoisomerization of azo unit of the catalysts. In conclusion, titled palladium complexes provide a green, sustainable, cost-effective, and convenient process to synthesize SMC products at multi-gram-scale reaction.
Pd-NHCs Enabled Suzuki-Miyaura Cross-Coupling of Arylhydrazines via C–N Bond Cleavage
Zeng, Xiao-Xiao,Li, Dong-Hui,Zhou, Zhen,Xu, Chang,Liu, Feng-Shou
supporting information, (2021/03/01)
We describe a highly efficient protocol for cross-coupling of phenylhydrazines with arylboronic acids by Pd-NHCs under aerobic reaction condition. A series of well-defined Pd-NHCs complexes were evaluated and the relationship between the structure and the catalytic properties was investigated. It was disclosed that the Pd-PEPPSI-IPr proved to be the robust precatalyst, providing access to a range of (hetero)biaryls in good to excellent yields.
Compound, organic luminescent material and organic electroluminescent device
-
Paragraph 0127; 0128; 0129; 0136; 0137; 0138, (2021/08/19)
The invention provides a compound as shown in a general formula (I), which has a mother structure of sym-triphenyl substituted anthracene, is high in bond energy among atoms, has good thermal stability, is beneficial to solid-state accumulation among molecules, is large in bandwidth, has a light-emitting region in a blue light region, is high in light-emitting intensity, and has a proper energy level with adjacent levels. And injection and migration of excitons are facilitated. When the compound is used as a blue light host material in a luminescent layer, the driving voltage of an organic electroluminescent device can be effectively reduced, the luminous efficiency is improved, and the service life is prolonged. The invention also provides an organic electroluminescent device and a display device containing the compound of the general formula (I).
Synthesis of tetranuclear complex of Pd(II) with thiosemicarbazone ligands derived from 2-quinolone and its catalytic evaluation in Suzuki–Miyaura-type coupling reactions and alkoxylation of chloroquinolines
Nandhini, Sundar,Dharani, Sivadasan,Elamathi, Chennakrishnan,Dallemer, Frederic,Prabhakaran, Rathinasabapathi
, (2021/09/06)
A tetranuclear palladium(II) complex [(Pd(H-6MOQtsc-Ph))4] was obtained from the reaction between 6-methyl-2-oxo-1,2-dihydroquinoline-3-carboxaldehyde-4(N)-phenylthiosemicarbazone [H2-6MOQtsc-Ph] and K2[PdCl4]. The ligand and the Pd(II) complex were characterized by Fourier transform infrared spectroscopy (FT-IR), UV–visible and 1H NMR spectroscopy. X-ray diffraction studies confirmed the tetrameric nature of the complex with the coordination of ligand through quinolone carbonyl, azomethine nitrogen and thiolate sulfur atoms, and the fourth site is occupied by 2-quinolone nitrogen atom of the adjacent ligand. The synthesized complex was tested as catalyst in Suzuki–Miyaura coupling reaction between various chloroquinoline derivatives with phenylboronic acid. The reactions afforded unexpected C-alkoxylated (C-O coupling) products instead of more expected C-arylated (C-C coupling) products in the respective alcoholic mediums. However, the reactions with traditional aryl halides probed with very good yield of the corresponding C-C coupling products.
