7431-45-0Relevant articles and documents
Sustainable and recyclable magnetic nanocatalyst of 1,10-phenanthroline Pd(0) complex in green synthesis of biaryls and tetrazoles using arylboronic acids as versatile substrates
Bagherzadeh, Nastaran,Sardarian, Ali Reza,Eslahi, Hassan
, (2021/04/02)
A magnetic nanocatalyst was purveyed as a heterogeneous recoverable palladium-based catalyst anchored on green, sustainable and phosphine free support. Resulted Fe3O4@SiO2-Phen-Pd(0) nanocatalyst bearing powerful phenanthroline ligand was thoroughly characterized by physicochemical approaches like UV–vis, FT-IR, EDX, XRD, TGA, ICP, VSM, DLS, FESEM, and TEM analyses. After finding trustable data, the obtained magnetic catalyst was considered to be applied in the Suzuki-Miyaura type C-C couplings and getting corresponding tetrazoles using arylboronic acid derivatives as alternate precursors of aromatic halides and stupendous data were observed.
Microwave-assisted synthesis of phenylpyrimidine derivatives via Suzuki-Miyaura reactions in water
Le, Yi,Zhang, Yan,Wang, Qin,Rao, Nian,Li, Dan,Liu, Li,Ouyang, Guiping,Yan, Longjia
supporting information, (2021/02/21)
An efficient method was developed to prepare biphenylpyrimidine scaffolds via a Suzuki-Miyaura coupling reaction. In this procedure, the products were synthesized under microwave irradiation in water and analogues of biguanidine were employed as ligands.
Ruthenium-catalysedmeta-selective CAr-H bond alkylationviaa deaminative strategy
Zhu, Ze-Fan,Chen, Guang-Le,Liu, Feng
supporting information, p. 3411 - 3414 (2021/04/07)
The use of aliphatic amines as alkylating reagents in organic synthesisviaC-N bond activation remains underdeveloped. We herein describe a novel ruthenium-catalysed and directing-group assisted protocol for the synthesis ofmeta-alkylated arenesviadual C-H and C-N activation. Bench-stable and easily handled redox-active Katritzky pyridinium salts derived from abundant amines and amino acid species were used as alkyl radical precursors. This catalytic reaction could accommodate a broad range of functional groups and provide access to variousmeta-alkylated products.
Cyclometallated 2-Phenylpyrimidine Derived Platinum Complexes: Synthesis and Photophysical Properties
Fecková, Michaela,Kahlal, Samia,Roisnel, Thierry,Saillard, Jean-Yves,Boixel, Julien,Hruzd, Mariia,le Poul, Pascal,Gauthier, Sébastien,Robin-le Guen, Fran?oise,Bure?, Filip,Achelle, Sylvain
, p. 1592 - 1600 (2021/04/28)
A series of five platinum (II) complexes based on 2-phenylpyrimidine ligands have been designed. Pyridine and chloride were used as auxiliary ligands. These complexes exhibit a slightly distorted square-planar geometry. The nature and position of substitu
2-Phosphinoimidazole Ligands: N-H NHC or P-N Coordination Complexes in Palladium-Catalyzed Suzuki-Miyaura Reactions of Aryl Chlorides
Martinez, Erin E.,Larson, Alexandra J. S.,Fuller, Sydney K.,Petersen, Kathryn M.,Smith, Stacey J.,Michaelis, David J.
supporting information, p. 1560 - 1564 (2021/05/29)
We report the synthesis of two palladium 2-(dialkylphosphino)imidazole complexes and demonstrate their activity as catalysts for Suzuki-Miyaura reactions with (hetero)aryl chlorides at room temperature. Our mechanistic studies demonstrate that these palladium complexes exist as an equilibrium mixture between the P-N coordinated and N-H NHC forms of ligand. Our studies suggest that the N-H NHC form may be important for high catalytic activity in Suzuki-Miyaura reactions with aryl chlorides. These reactions proceed at or near room temperature in good to excellent yields. Heteroaryl chlorides are also reactive at lower catalyst loadings.
Importance of Two-Electron Processes in Fe-Catalyzed Aryl-(hetero)aryl Cross-Couplings: Evidence of Fe0/FeIICouple Implication
Wowk, Vincent,Rousseau, Lidie,Lefèvre, Guillaume
supporting information, p. 3253 - 3266 (2021/10/12)
We demonstrate in this work that two drastically distinct mechanisms can be involved in aryl-(hetero)aryl Fe-mediated cross-couplings between Grignard reagents and organic halides, depending on the nature of the latter. (Hetero)aryl electrophiles, which easily undergo one-electron reduction, can be involved in a FeII/FeIII coupling sequence featuring an in situ generated organoiron(II) species, akin to their aliphatic analogues. On the other hand, less easily reduced substrates can be activated by transient Fe0 species formed by the reduction of the precatalyst. In this case, the coupling mechanism relies on two-electron elementary steps involving the Fe0/FeII redox couple and proceeds by an oxidative addition/reductive elimination sequence. Hammett analysis shows that both those elementary steps are faster for electrophiles substituted by electron-withdrawing groups. The two mechanisms discussed herein can be involved concomitantly for electrophiles displaying an average oxidative power. Attesting to the feasibility of the aforementioned bielectronic mechanism, high-spin organoiron(II) intermediates formed by two-electron oxidative addition onto (hetero)aryl halides in catalytically relevant conditions were also characterized for the first time. Those results are sustained by paramagnetic 1H NMR, kinetics monitoring, and density functional theory (DFT) calculations.
Chromium-Catalyzed Reductive Cleavage of Unactivated Aromatic and Benzylic C-O Bonds
Yuan, Shuqing,Ling, Liang,Tang, Jinghua,Luo, Meiming,Zeng, Xiaoming
supporting information, p. 3343 - 3350 (2021/07/02)
Reductive cleavage of aromatic and benzylic C-O bonds by chromium catalysis is reported. This deoxygenative reaction was promoted by low-cost CrCl 2precatalyst combined with poly(methyl hydrogen siloxane) as the mild reducing agent, providing a strategy in forming reduced motifs by cleavage of unactivated C-O bonds. A range of functional groups such as bromide, chloride, fluoride, hydroxyl, amino, and alkoxycarbonyl can be retained in the reduction.
Immobilized Pd on a NHC functionalized metal–organic framework MIL-101(Cr): an efficient heterogeneous catalyst in Suzuki?Miyaura coupling reaction in water
Khalafi-Nezhad, Ali,Niknam, Esmaeil,Panahi, Farhad
, (2020/02/05)
A novel Pd?NHC functionalized metal–organic framework (MOF) based on MIL-101(Cr) was synthesized and used as an efficient heterogeneous catalyst in the C-C bond formation reactions. Using this heterogeneous Pd catalyst system, the Suzuki?Miyaura coupling reaction was accomplished well in water, and coupling products were obtained in good to excellent yields in short reaction time. The Pd?NHC?MIL-101(Cr) was characterized using some different techniques, including Fourier transform-infrared, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy, inductively coupled plasma and elemental analysis. The microscopic techniques showed the discrete octahedron structure of MIL-101(Cr), which is also stable after chemical modification process to prepare the catalyst system. The TEM images of the catalyst showed the existence of palladium nanoparticles immobilized in the structure of the catalyst, while no reducing agent was used. It seems that the NHC groups and imidazolium moieties in the structure of the MOF can reduce Pd (II) to Pd (0) species. This modified MOF substrate can also prevent aggregation of Pd nanoparticles, resulting in high stability of them in organic transformation. The Pd?NHC?MIL-101(Cr) catalyst system could be simply extracted from the reaction mixture, providing an efficient synthetic method for the synthesis of biaryls derivatives using the aforementioned coupling reaction. The Pd?NHC?MIL-101(Cr) catalyst could be recycled in this organic reaction with almost consistent catalytic efficiency.
Meta-dehydrogenative alkylation of arenes with ethers, ketones, and esters catalyzed by ruthenium
Li, Gang,Gao, Yuan,Jia, Chunqi,Wang, Shichong,Yan, Bingxu,Fang, Yu,Yang, Suling
supporting information, p. 8758 - 8763 (2020/12/02)
A meta-dehydrogenative alkylation of arenes with cyclic ethers, ketones, and esters catalyzed by ruthenium is achieved in the presence of a di-tert-butyl peroxide (DTBP) oxidant. Interestingly, when quinoline and isoquinoline are employed as the directing group, or a chain ether as alkylation reagent, the system produces Minisci reaction products. Mechanistic study indicates that meta-dehydrogenative alkylation is a radical process initiated by DTBP with the assistance of a CAr-Ru bond ortho/para-directing effect.
Directing Group-Promoted Inert C?O Bond Activation Using Versatile Boronic Acid as a Coupling Agent
Ambre, Ram,Wang, Ting-Hsuan,Xian, Anmei,Chen, Yu-Shiuan,Liang, Yu-Fu,Jurca, Titel,Zhao, Lili,Ong, Tiow-Gan
, p. 17021 - 17026 (2020/11/30)
A simple Ni(cod)2 and carbene mediated strategy facilitates the efficient catalytic cross-coupling of methoxyarenes with a variety of organoboron reagents. Directing groups facilitate the activation of inert C?O bonds in under-utilized aryl methyl ethers enabling their adaptation for C?C cross-coupling reactions as less toxic surrogates to the ubiquitous haloarenes. The method reported enables C?C cross-coupling with readily available and economical arylboronic acid reagents, which is unprecedented, and compares well with other organoboron reagents with similarly high reactivity. Extension to directing group assisted chemo-selective C?O bond cleavage, and further application towards the synthesis of novel bifunctionalized biaryls is reported. Key to the success of this protocol is the use of directing groups proximal to the reaction center to facilitate the activation of the inert C?OMe bond.
