3956-07-8Relevant academic research and scientific papers
Recyclable N-heterocyclic carbene/palladium catalyst on graphene oxide for the aqueous-phase Suzuki reaction
Park, Jung Hyun,Raza, Faizan,Jeon, Su-Ji,Kim, Hye-In,Kang, Tae Woog,Yim, Dabin,Kim, Jong-Ho
, p. 3426 - 3430 (2014)
Graphene oxide (GO) was functionalized with a N-heterocyclic carbene (NHC) precursor, 3-(3-aminopropyl)-1-methylimidazolium bromide ([APMIm][Br]) for the immobilization of palladium catalyst. The GO-supported NHC precursor (IMGO) formed a stable complex with Pd(OAc)2 (GO-NHC-Pd), which showed excellent catalytic activity and fast reaction kinetics in the aqueous-phase Suzuki reaction of aryl bromides and chlorides at relatively mild conditions (1 h at 50 °C). The GO-NHC-Pd catalyst was reused several times without any loss of its catalytic activity in the Suzuki reaction of aryl bromide.
A “universal” catalyst for aerobic oxidations to synthesize (hetero)aromatic aldehydes, ketones, esters, acids, nitriles, and amides
Bartling, Stephan,Beller, Matthias,Chandrashekhar, Vishwas G.,Jagadeesh, Rajenahally V.,Rabeah, Jabor,Rockstroh, Nils,Senthamarai, Thirusangumurugan
supporting information, p. 508 - 531 (2022/02/11)
Functionalized (hetero)aromatic compounds are indispensable chemicals widely used in basic and applied sciences. Among these, especially aromatic aldehydes, ketones, carboxylic acids, esters, nitriles, and amides represent valuable fine and bulk chemicals, which are used in chemical, pharmaceutical, agrochemical, and material industries. For their synthesis, catalytic aerobic oxidation of alcohols constitutes a green, sustainable, and cost-effective process, which should ideally make use of active and selective 3D metals. Here, we report the preparation of graphitic layers encapsulated in Co-nanoparticles by pyrolysis of cobalt-piperazine-tartaric acid complex on carbon as a most general oxidation catalyst. This unique material allows for the synthesis of simple, functionalized, and structurally diverse (hetero)aromatic aldehydes, ketones, carboxylic acids, esters, nitriles, and amides from alcohols in excellent yields in the presence of air.
Half-Sandwich Iridium Complexes Based on β-Ketoamino Ligands: Preparation, Structure, and Catalytic Activity in Amide Synthesis
Wang, Yang,Guo, Wen,Guan, Ai-Lin,Liu, Shuang,Yao, Zi-Jian
, p. 11514 - 11520 (2021/07/31)
A series of β-ketoamino-based N,O-chelate half-sandwich iridium complexes with the general formula [Cp*IrClL] have been prepared in good yields. These air-insensitive iridium complexes showed desirable catalytic activity in an amide preparation under mild conditions. A number of amides with diverse substituted groups were furnished in a one-pot reaction with good-to-excellent yields through an amidation reaction of NH2OH·HCl with aldehydes in the presence of these iridium(III) precursors. The excellent catalytic activity, mild reaction conditions, and broad substrate scope gave this type of iridium catalyst potential for use in industry. All of the obtained iridium complexes were well characterized by different spectroscopy techniques. The exact molecular structure of complex 3 has been confirmed by single-crystal X-ray analysis.
Efficient nitriding reagent and application thereof
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Paragraph 0298-0300, (2021/03/31)
The invention discloses an efficient nitriding reagent and application thereof, wherein the nitriding reagent comprises nitrogen oxide, an active agent, a reducing agent and an organic solvent. By applying the nitriding reagent, nitrogen-containing compounds such as amide, nitrile and the like can be produced, and the method is simple in condition, low in waste discharge amount and simple in reaction equipment.
Design, synthesis and bioactivity evaluation of novel pyrazole linked phenylthiazole derivatives in context of antibacterial activity
Patel, Bhautikkumar,Zunk, Matthew,Grant, Gary,Rudrawar, Santosh
, (2021/03/14)
Methicillin-resistant Staphylococcus aureus (MRSA) infections are a significant burden both clinically and economically worldwide. Increasing resistance to current antibiotics requires an urgent investigation into novel classes of antimicrobial agents. This study presents a structure–activity relationship (SAR) rationale for pyrazole linked phenylthiazole analogues as new antibacterial agents. A library of 23 novel pyrazole linked phenylthiazole compounds were synthesised, followed by screening for antimicrobial activity against five bacterial species and two fungi. The most active compound 14b has shown promising antibacterial activity against the Gram-positive methicillin-resistant Staphylococcus aureus (MRSA, ATCC 43300) strain (MIC 4 μg/mL). Furthermore, the active pyrazole linked phenylthiazole compound exhibited a better toxicity profile than standard antibiotics. In summary, these results demonstrate that a pyrazole linked phenylthiazole scaffold has potential as a lead for further investigation to afford novel antibacterial agents.
Visible light-mediated synthesis of amides from carboxylic acids and amine-boranes
Chen, Xuenian,Kang, Jia-Xin,Ma, Yan-Na,Miao, Yu-Qi
supporting information, p. 3595 - 3599 (2021/06/06)
Here, a photocatalytic deoxygenative amidation protocol using readily available amine-boranes and carboxylic acids is described. This approach features mild conditions, moderate-to-good yields, easy scale-up, and up to 62 examples of functionalized amides with diverse substituents. The synthetic robustness of this method was also demonstrated by its application in the late-stage functionalization of several pharmaceutical molecules.
Unlocking Amides through Selective C–N Bond Cleavage: Allyl Bromide-Mediated Divergent Synthesis of Nitrogen-Containing Functional Groups
Govindan, Karthick,Chen, Nian-Qi,Chuang, Yu-Wei,Lin, Wei-Yu
supporting information, p. 9419 - 9424 (2021/11/30)
We report a new set of reactions based on the unlocking of amides through simple treatment with allyl bromide, creating a common platform for accessing a diverse range of nitrogen-containing functional groups such as primary amides, sulfonamides, primary amines, N-acyl compounds (esters, thioesters, amides), and N-sulfonyl esters. The method has potential industrial applicability, as demonstrated through gram-scale syntheses in batch and in a continuous flow system.
Hydration of Cyanohydrins by Highly Active Cationic Pt Catalysts: Mechanism and Scope
Li, Chengcheng,Chang, Xiao-Yong,Huo, Luqiong,Tan, Haibo,Xing, Xiangyou,Xu, Chen
, p. 8716 - 8726 (2021/07/26)
Cyanohydrins (α-hydroxy nitriles) are a special type of nitriles that readily decompose into hydrogen cyanide (HCN) and the corresponding carbonyl compounds. Hydration of cyanohydrins that are readily available through cyanation of aldehydes and ketones provides the most straightforward route to valuable α-hydroxyamides. However, due to low stability of cyanohydrins and deactivation of the catalysts by the released HCN, catalytic direct hydration of cyanohydrins still remains largely unsolved. As a general trend, cyanohydrins containing bulkier substituents, such as α,α-diaryl cyanohydrins, degrade more quickly and thus are more difficult to be hydrated. Here, we report development of cationic platinum catalysts that exhibit high reactivity for hydration of various cyanohydrins. Detailed mechanistic investigations for hydration of nitriles by (PμP)Pt(PR2OH)X(OTf) reveal a catalytic cycle involving the formation of a five-membered metallacyclic intermediate and subsequent hydrolysis via attacking on the phosphorus of the secondary phosphine oxide (PR2OH) ligand by H2O. We discovered that Pt catalyst A bearing the electron-rich, appropriately small-bite-angle bisphosphine ligand provides super reactivity for hydration of cyanohydrins. The hydration reactions catalyzed by A proceed at ambient temperatures and occur with a wide variety of cyanohydrins, including the most difficult α,α-diaryl cyanohydrins, with good turnover numbers.
Transamidation for the Synthesis of Primary Amides at Room Temperature
Chen, Jiajia,Lee, Sunwoo,Xia, Yuanzhi
supporting information, (2020/05/05)
Various primary amides have been synthesized using the transamidation of various tertiary amides under metal-free and mild reaction conditions. When (NH4)2CO3 reacts with a tertiary amide bearing an N-electron-withdrawing substituent, such as sulfonyl and diacyl, in DMSO at 25 °C, the desired primary amide product is formed in good yield with good funcctional group tolerance. In addition, N-tosylated lactam derivatives afforded their corresponding N-tosylamido alkyl amide products via a ring opening reaction.
Half-Sandwich Iridium Complexes for the One-Pot Synthesis of Amides: Preparation, Structure, and Diverse Catalytic Activity
Fan, Xiao-Nan,Deng, Wei,Liu, Zhen-Jiang,Yao, Zi-Jian
, p. 16582 - 16590 (2020/11/13)
Several types of air-stable N,O-coordinate half-sandwich iridium complexes containing Schiff base ligands with the general formula [Cp*IrClL] were synthesized in good yields. These stable iridium complexes displayed a good catalytic efficiency in amide synthesis. A variety of amides with different substituents were obtained in a one-pot procedure with excellent yields and high selectivities through the amidation of aldehydes with NH2OHHCl and nitrile hydration under the catalysis of complexes 1-4. The excellent and diverse catalytic activity, mild conditions, broad substance scope, and environmentally friendly solvent make this system potentially applicable in industrial production. Half-sandwich iridium complexes 1-4 were characterized by NMR, elemental analysis, and IR techniques. Molecular structures of complexes 2 and 3 were confirmed by single-crystal X-ray analysis.
