25372-03-6Relevant academic research and scientific papers
A post-synthetically modified metal-organic framework for copper catalyzed denitrative C-N coupling of nitroarenes under heterogeneous conditions
Maity, Tanmoy,Ghosh, Pameli,Das, Soma,Saha, Debraj,Koner, Subratanath
, p. 5568 - 5575 (2021/04/06)
Here we report, for the first time, the Ullmann C-N coupling reaction of nitroarenes which is achieved by using a copper containing metal-organic framework (MOF) catalyst under heterogenous conditions. The ready availability of nitroarenes and their low cost have made them ideal replacements for haloarenes as electrophilic coupling partners. Notably, the reaction protocol suppresses the by-product formation in the catalytic reaction. The catalyst has been designed and synthesized by two step post-synthesis functionalization of a MOF,viz.dabco MOF-1 with a -NH2functional group (DMOF-NH2). In the post-synthetic treatment, salicylaldehyde has been used for organic modification first and then copper(ii) was successfully incorporated onto the inner surface of the porous material. The hybrid porous solid thus obtained has been employed in the catalytic C-N coupling reaction of nitroarenes with a wide variety of amines under heterogeneous conditions, which displayed very high turnover frequencies (TOF) in catalytic reactions attesting its efficacy towards theN-arylation reaction.
NHC ligand-based half-sandwich iridium complexes: synthesis, structure and catalytic activity in acceptorless dehydrogenation and transfer hydrogenation
Deng, Wei,Jin, Yan,Li, Rong-Jian,Liu, Zhen-Jiang,Wang, Yang,Yao, Zi-Jian
, p. 19002 - 19010 (2021/10/29)
A set of neutral C,C-chelate half-sandwich iridium(iii) complexes have been prepared with NHC ligands that contain pendant aromatic rings as potentially chelating donor sites. The catalytic activity of such iridium complexes has been investigated for the acceptorless dehydrogenation (AD) reactions of alcohols and for the transfer hydrogenation reactions of ketones. The prepared iridium(iii) complexes show excellent catalytic activity for AD reactions of a wide range of secondary alcohols, and they are also shown to be effective for the synthesis of aldehydes from primary alcohols without the observation of undesired byproducts such as esters. Additionally, these complexes are also highly efficient in transfer hydrogenation of ketones and aldehydes, which give the alcohols in good yields under mild conditions. The exact structure and bonding mode of the NHC-based iridium complexes was identified using various spectroscopic methods and single crystal X-ray analysis.
L-Proline N-oxide dihydrazides as an efficient ligand for cross-coupling reactions of aryl iodides and bromides with amines and phenols
Ding, Zhiqiang,Nie, Nan,Chen, Tian,Meng, Lingxin,Wang, Gongshu,Chen, Zhangpei,Hu, Jianshe
supporting information, (2020/12/21)
A novel catalytic system based on L-proline N-oxide/CuI was developed and applied to the cross-coupling reactions of various N- and O- nucleophilic reagents with aryl iodides and bromides. This strategy featured in the employment of an-proline derived dihydrazides N-oxide compound as the superior supporting ligand. By using this protocol, a variety of products, including N-arylimidazoles, N-arylpyrazoles, N-arylpyrroles, N-arylamines, and aryl ethers, were synthesized with up to 99% yield.
A Pd/Cu-Free magnetic cobalt catalyst for C-N cross coupling reactions: synthesis of abemaciclib and fedratinib
Hajipour, Abdol R.,Khorsandi, Zahra,Sarfjoo, Mohamad Reza,Varma, Rajender S.
supporting information, p. 5222 - 5229 (2021/07/29)
Herein, the synthesis of a nano-catalytic system comprising magnetic nanoparticles as the core and edible natural ligands bearing functional groups as supports for cobalt species is described. Subsequent to its characterization, the efficiency of the catalyst was investigated for C-N cross-coupling reactions using assorted derivatives of amines and aryl halides. This novel and easily accessible Pd- and Cu-free catalyst exhibited good catalytic activity in these reactions using γ-valerolactone (GVL) at room temperature; good recyclability bodes well for the future application of this strategy. The introduced catalytic system is attractive in view of the excellent efficiency in an array of coupling reactions and its versatility is illustrated in the synthesis of abemaciclib and fedratinib, which are FDA-approved new and significant anti-cancer medicinal compounds that are prepared under green reaction conditions.
Palladium-Catalyzed Cyanation of Aryl Halides Using Formamide and Cyanuric Chloride as a New “CN” Source
Niknam, Esmaeil,Panahi, Farhad,Khalafi-Nezhad, Ali
, p. 2699 - 2707 (2020/04/08)
A new source of “CN” employing formamide and cyanuric chloride is introduced for the cyanation reactions. The treatment of formamide and 2,4,6-trichloro-1,3,5-triazine (TCT; cyanuric chloride) afforded an efficient cyanating agent which it can be used as a nontoxic, readily available, and non-expensive reagent in the cyanation transformations. In this study, palladium-catalyzed cyanation of aryl halides was successfully accomplished using this new “CN” source in high yields.
Preparation method of diarylamine compound
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Paragraph 0070; 0071; 0072, (2019/04/26)
The invention relates to a preparation method of a diarylamine compound. Specifically, under the catalysis of cuprous oxide supported by chitosan, the arylation reaction used for a nitrogen-containingheterocyclic compound is achieved, and the corresponding diarylamine compound is obtained. The preparation method of the diarylamine compound has the advantages that the process conditions are simple, the yield is good, the operability is strong, and the functional group tolerance is wide.
Functional 1,8-naphthyridine copper(I) complex as efficient catalyst for n-arylation of imidazoles coupling reactions
Gou, Gao-Zhang,Wu, Na,Zhang, Ju-Cheng,Shi, Ling,Liu, Gui-Yang,Liu, Wei,Mang, Chao-Yong,Chi, Shao-Ming
, p. 181 - 185 (2018/02/28)
The functional 1,8-naphthyridine copper(I) complex, synthesized through a non-catalyst C(sp3)-H methylenation, catalyzes the cross-coupling reaction of aryl halides with imidazoles, by C?N bond formation. The Cu(I) complex catalyzes the reaction with a low catalyst loading (1%, molar fraction) and cheap base even under aerobic conditions. The procedure tolerates aryl halides with various functional groups (such as methyl, methoxy, acetyl, fluoro, nitrile and nitro groups) and gives the corresponding coupling products in moderate to high yields.
Salen complex of Cu(II) supported on superparamagnetic Fe3O4@SiO2 nanoparticles: an efficient and magnetically recoverable catalyst for N-arylation of imidazole with aryl halides
Sardarian, Ali Reza,Zohourian-Mashmoul, Neda,Esmaeilpour, Mohsen
, p. 1101 - 1109 (2018/02/21)
Abstract: The Fe3O4@SiO2/Salen-Cu(II) nanocatalyst is reported as a thermally and air-stable, economical, and magnetically recoverable heterogeneous catalyst for the selective and efficient N-(hetero)arylation of imidazole. Only by adding a small amount of the catalyst (0.4?mol% Cu) to the reactants and heating under air, the new presented method provides a variety of functionalized and hindered N-(hetero)arylimidazoles in good to excellent yields within short reaction times. The catalyst could be easily recovered with the aid of a permanent magnet and reused up to five consecutive runs without significant loss of activity. Also, the leaching of Cu was negligible after the fifth recycle. Particularly, using either (hetero)aryl iodides or bromides as arylating agents and the need of only small amount of the magnetically recoverable heterogeneous copper-based nanocatalyst make this method low-cost, environmentally benign, and easy to use. Graphical abstract: [Figure not available: see fulltext.].
Preparation method of aromatic nitrile compound or heteroaromatic nitrile compound
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Paragraph 0043; 0045; 0157-0159, (2018/11/03)
The invention discloses a preparation method of an aromatic nitrile compound or a heteroaromatic nitrile compound. The preparation method comprises: under the protection of an inert gas, in a solvent,under the actions of a nickel catalyst, a ligand, metal zinc and an additive, carrying out a reaction on a cyanation reagent and halogenated aromatic hydrocarbon or halogenated heteroaromatic hydrocarbon. According to the present invention, by using the inexpensive and easily-available nickel catalyst and the ligand, the halogenated aromatic hydrocarbon or halogenated heteroaromatic hydrocarbon,especially the chlorinated aromatic hydrocarbon or chlorinated heteroaromatic hydrocarbon with characteristics of low price, easy obtaining and low reaction activity can mildly and efficiently react with the cyanation reagent with low toxicity to prepare the aromatic nitrile compound or heteroaromatic nitrile compound; and the preparation method has advantages of simple operation, mildness, high efficiency and the like, and further has characteristics of good functional group compatibility, good universality of substrate and the like.
Strategically designed azolyl-carboxylate MOFs for potential humid CO2 capture
Nandi, Shyamapada,Haldar, Sattwick,Chakraborty, Debanjan,Vaidhyanathan, Ramanathan
, p. 535 - 543 (2017/01/11)
Development of solid sorbents with optimal CO2 capture characteristics is key to improving the efficiency of PSA based CO2 separation. Of the several potential sorbents, metal organic frameworks (MOFs) hold a key niche. This is owing to their modular tunable structures and manipulatable adsorption sites. Yet, developing a MOF that meets the multiple demands of a gas-separation sorbent remains a challenge. Particularly, tuning them to adsorb CO2 over the more polar water is quite difficult. The presence of highly polarizing metal centers and oxygen-rich sites in MOFs makes it difficult to retain their CO2 adsorption capacities under humid gas streams. However, tailoring the organic framework to incorporate humid CO2 capture properties should be feasible. Along these lines, here we have developed a family of iso-structural MOFs built from bi-functional ligands that carry basic azolyl and chelating carboxylate groups together. Importantly, the framework is built by employing acetate moieties as ‘modulators’; they provide a hydrophobic lining to the pore-walls. This not only enables selective adsorption of CO2, but also helps retain about 80% of the capture capacity even upon exposure to 75% RH. Along with its other advantageous features: high CO2 uptake and selectivity (3 mmol g?1 and s(CO2-N2) = ～500 for 85N2?:?15CO2@303 K); surface area: ～700 m2 g?1, working capacity: 2.6 mmol g?1; optimal HOA (22-30 kJ mol?1) and CO2 kinetics (Dc = 1.02 × 10?8 m2 s?1), these MOFs can qualify as efficient candidates for humid CO2 capture. Furthermore, we identify the most-favorable CO2 adsorption sites via simulated annealing methods, from which the presence of polarized CO2 molecules located adjacent to the π-electron rich pore walls can be seen. Importantly, these polarized molecules form T-shaped configurations among themselves via C(δ+ve)?O(δ?ve) interactions resembling those found in solid CO2, a cooperative feature that is not observed in the other CO2 molecules in the structure, which are not proximal to the polarizing walls.
