5400-78-2Relevant academic research and scientific papers
CeO2-nanocubes as efficient and selective catalysts for the hydroboration of carbonyl groups
Bhawar, Ramesh,Bose, Shubhankar Kumar,Patil, Kiran S.
supporting information, p. 15028 - 15034 (2021/09/04)
The CeO2-nanoparticle catalysed hydroboration of carbonyl compounds with HBpin (pin = OCMe2CMe2O) is reported to afford the corresponding borate esters in excellent yield. A series of aromatic and aliphatic aldehydes and ketones having synthetically important functional groups were well-Tolerated under mild reaction conditions. Further, chemoselective hydroboration of aldehydes over other reducible functional groups such as ketone, nitrile, hydroxide, alkene, alkyne, amide, ester, nitro, and halides was achieved. Importantly the catalyst can be recycled up to ten runs with slight loss in activity. This journal is
Identification of Diarylurea Inhibitors of the Cardiac-Specific Kinase TNNI3K by Designing Selectivity against VEGFR2, p38α, and B-Raf
Cheung, Mui,Desai, Tina A.,Fries, Harvey,Gatto, Gregory J.,Graves, Alan P.,Holt, Dennis A.,Kallander, Lara S.,Patterson, Jaclyn R.,Shewchuk, Lisa,Stoy, Patrick,Totoritis, Rachel,Wang, Liping
, p. 15651 - 15670 (2021/11/16)
A series of diarylurea inhibitors of the cardiac-specific kinase TNNI3K were developed to elucidate the biological function of TNNI3K and evaluate TNNI3K as a therapeutic target for the treatment of cardiovascular diseases. Utilizing a structure-based design, enhancements in kinase selectivity were engineered into the series, capitalizing on the established X-ray crystal structures of TNNI3K, VEGFR2, p38α, and B-Raf. Our efforts culminated in the discovery of an in vivo tool compound 47 (GSK329), which exhibited desirable TNNI3K potency and rat pharmacokinetic properties as well as promising kinase selectivity against VEGFR2 (40-fold), p38α (80-fold), and B-Raf (>200-fold). Compound 47 demonstrated positive cardioprotective outcomes in a mouse model of ischemia/reperfusion cardiac injury, indicating that optimized exemplars from this series, such as 47, are favorable leads for discovering novel medicines for cardiac diseases.
Selective and Additive-Free Hydrogenation of Nitroarenes Mediated by a DMSO-Tagged Molecular Cobalt Corrole Catalyst
Sch?fberger, Wolfgang,Timelthaler, Daniel,Topf, Christoph
supporting information, p. 2114 - 2120 (2021/07/22)
We report on the first cobalt corrole that effectively mediates the homogeneous hydrogenation of structurally diverse nitroarenes to afford the corresponding amines. The given catalyst is easily assembled prior to use from 4-tert-butylbenzaldehyde and pyrrole followed by metalation of the resulting corrole macrocycle with cobalt(II) acetate. The thus-prepared complex is self-contained in that the hydrogenation protocol is free from the requirement for adding any auxiliary reagent to elicit the catalytic activity of the applied metal complex. Moreover, a containment system is not required for the assembly of the hydrogenation reaction set-up as both the autoclave and the reaction vessels are readily charged under a regular laboratory atmosphere.
Chemoselective reduction of nitroarenes, N-acetylation of arylamines, and one-pot reductive acetylation of nitroarenes using carbon-supported palladium catalytic system in water
Zeynizadeh, Behzad,Mohammad Aminzadeh, Farkhondeh,Mousavi, Hossein
, p. 3289 - 3312 (2021/05/11)
Developing and/or modifying fundamental chemical reactions using chemical industry-favorite heterogeneous recoverable catalytic systems in the water solvent is very important. In this paper, we developed convenient, green, and efficient approaches for the chemoselective reduction of nitroarenes, N-acetylation of arylamines, and one-pot reductive acetylation of nitroarenes in the presence of the recoverable heterogeneous carbon-supported palladium (Pd/C) catalytic system in water. The utilize of the simple, effective, and recoverable catalyst and also using of water as an entirely green solvent along with relatively short reaction times and good-to-excellent yields of the desired products are some of the noticeable features of the presented synthetic protocols. Graphic abstract: [Figure not available: see fulltext.].
Ruthenium complex based on [N,N,O] tridentate -2-ferrocenyl-2-thiazoline ligand for catalytic transfer hydrogenation
Badillo-Gómez,Sánchez-Rodríguez,Toscano,Gouygou,Ortega-Alfaro,López-Cortés
, (2020/12/14)
A method for the synthesis of a new phosphine-free [N,N,O]-tridentate Schiff base ligand L1 using the 2-Ferrocenyl-2-thiazoline as scaffold was developed. The 1,2-disubstituted ferrocene-based ligand was assembled using as key strategy the directed ortho-metalation (DoM) in 2-ferrocenyl-2-thiazoline. L1 was successfully obtained in 83% of overall yield after two-step synthesis. The coordination ability of L1 towards Ru(II) was evidenced and the resulting complex was characterized by IR, UV-vis and EPR. Its catalytic performance was tested in transfer hydrogenation of a variety of substrates giving moderate to excellent conversions.
Transfer hydrogenation via generation of hydride intermediate and base-free alcohol oxidation activity studies on designed ruthenium complexes derived from NNN pincer type ligands
Singh, Prasoon Raj,Maji, Ankur,Singh, Ovender,Singh, Udai P.,Ghosh, Kaushik
, (2020/03/27)
Ruthenium complexes(1–3) have been synthesized using pincer-type ligands L1 = (E)-2-((2-phenyl-2-(pyridin-2-yl)hydrazono)methyl)pyridine, L2 = (E)-2-(1-phenyl-2-(1-(pyridin-2-yl)ethylidene)hydrazinyl)pyridine, L3 = (E)-2-(phenyl(2-phenyl-2-(pyridin-2-yl)hydrazono) methyl)pyridine. The molecular structures of all the complexes 1, 2 and 3 were determined by using single crystal X-ray diffraction. These complexes showed excellent catalytic activities such as transfer hydrogenation and alcohol oxidation. Theoretical calculations have been performed to understand the electronic properties of all the complexes using B3LYP as a function and LANL2DZ as a basis set.
Efficient catalytic transfer hydrogenation reactions of carbonyl compounds by Ni(II)-diphosphine complexes
Venkatesh, Sadhana,Panicker, Rakesh R.,Lenin Kumar, Verdhi,Pavankumar,Viswanath, Nukala,Singh, Shangrila,Desikan, Rajagopal,Sivaramakrishna, Akella
, p. 2963 - 2977 (2020/11/03)
The catalytic transfer hydrogenation reactions of a series of aromatic and aliphatic carbonyl compounds were investigated using divalent Ni(II)-diphosphine complexes, [L2NiCl2] (where L2 = 1,1-bis(diphenylphosphino)methane (dppm), 1,2-bis(diphenylphosphino)ethane (dppe), 1,3-bis(diphenylphosphino)propane (dppp), 1,1-bis(diphenylphosphino)ferrocene (dppf), and N-butyl-N-(diphenylphosphino)-1,1-diphenylphosphinamine (dppba)). This is a single-step reaction in the presence of potassium hydroxide and isopropyl alcohol to afford the corresponding alcohols. This protocol tolerates other sensitive functional groups like olefinic double bonds and also achieves high chemoselectivity. All the reactions were monitored by GC and GC–MS. The plausible mechanism is also discussed. The method reported in the present article is simple, cost-effective, and provides excellent conversions. Nickel-diphosphine complexes appear as a potential alternative to expensive transition metal complexes.
Green synthesis of chiral aromatic alcohols with Lactobacillus kefiri P2 as a novel biocatalyst
Bayda?, Yasemin,Dertli, Enes,?ahin, Engin
, p. 1035 - 1045 (2020/03/03)
Biocatalytic reduction is a very important field of research in synthetic organic chemistry. Herein, three different Lactic Acid Bacteria (LAB) strains were evaluated for their bioreduction potential using acetophenone as a model substrate. Among these strains, Lactobacillus kefiri P2 strain was determined as the best asymmetric reduction biocatalyst. Reaction optimization parameters such as reaction time, temperature, agitation speed and pH were systematically optimized using Lactobacillus kefiri P2 strain and model substrate acetophenone. Under these optimized reaction conditions, secondary chiral alcohols were obtained by bioreduction of various prochiral ketones with results up to 99% enantiomeric excess. In addition, the steric and electronic effects of substituents on enantioselectivity and conversion were evaluated. It has been shown that Lactobacillus kefiri P2 biocatalyst was an effective catalyst for asymmetric reduction. This method provides an environmentally friendly method for the synthesis of optically pure alcohols and an alternative approach to chemical catalysts.
One-pot Chemoenzymatic Deracemisation of Secondary Alcohols Employing Variants of Galactose Oxidase and Transfer Hydrogenation
Yuan, Bo,Debecker, Damien P.,Wu, Xiaofeng,Xiao, Jianliang,Fei, Qiang,Turner, Nicholas J.
, p. 6191 - 6195 (2020/10/15)
Enantiomerically enriched chiral secondary alcohols serve as valuable building blocks for drug intermediates and fine chemicals. In this study the deracemisation of secondary alcohols to generate enantiomeric pure chiral alcohols has been achieved by combining enantio-selective enzymatic oxidation of a secondary alcohol, by a variant of GOase (GOase M3-5), with either non-selective ketone reduction via transfer hydrogenation (TH) or enantio-selective asymmetric transfer hydrogenation (ATH). Both the enzymatic oxidation system and the transition-metal mediated reduction system were optimised to ensure compatibility with each other resulting in a homogeneous reaction system. 1-(4-nitrophenyl)ethanol was generated with 99 % conversion and 98 % ee by the deracemisation method, and it has been extended to a series of other secondary alcohols with comparable results.
Method for preparing 1-ethyl-3-nitrobenzene
-
Paragraph 0022-0027; 0034-0038; 0045-0049; 0056-0060, (2019/12/08)
The invention discloses a method for preparing 1-ethyl-3-nitrobenzene. The method comprises the following steps: S1. sequentially adding methanol and m-nitroacetophenone into a reaction bottle, cooling the temperature of the reaction bottle to 0 DEG C, adding sodium borohydride in batches, carrying out a reaction at a normal temperature under normal pressure, concentrating methanol, carrying out extracting, merging organic phases, and carrying out concentrating, so as to obtain 1-(3-nitrobenzophenone)ethanol; S2. sequentially adding dichloromethane, the 1-(3-nitrobenzophenone)ethanol, imidazole, triphenyl phosphine and elemental iodine into the reaction bottle, carrying out a reaction at a normal temperature under normal pressure, carrying out extracting, merging organic phases, and carrying out concentrating, so as to obtain crude 1-(1-iodoethyl)-3-nitrobenzene; and S3. dissolving the crude 1-(1-iodoethyl)-3-nitrobenzene in a polar solvent, adding sodium borohydride in batches, carrying out a reaction at a normal temperature under normal pressure, carrying out extracting, merging organic phases, carrying out concentrating, carrying out reduced-pressure distillation, thereby obtaining pure 1-ethyl-3-nitrobenzene. According to the method for preparing the 1-ethyl-3-nitrobenzene, disclosed by the invention, the reaction conditions are mild, a preparation process and purificationsteps are safe and simple, the product yield is high, and thus, industrialization is convenient to achieve.
