956-02-5Relevant articles and documents
Selective C-C bonds formation, N-alkylation and benzo[d]imidazoles synthesis by a recyclable zinc composite
Zhu, Guanxin,Duan, Zheng-Chao,Zhu, Haiyan,Ye, Dongdong,Wang, Dawei
supporting information, p. 266 - 270 (2021/08/06)
Earth abundant metals are much less expensive, promising, valuable metals and could be served as catalysts for the borrowing hydrogen reaction, dehydrogenation and heterocycles synthesis, instead of noble metals. The uniformly dispersed zinc composites were designed, synthesized and carefully characterized by means of XPS, EDS, TEM and XRD. The resulting zinc composite showed good catalytic activity for the N-alkylation of amines with amines, ketones with alcohols in water under base-free conditions, while unsaturated carbonyl compounds could also be synthesized by tuning the reaction conditions. Importantly, it was the first time to realize the synthesis of 2-aryl-1H-benzo[d]imidazole derivatives by using this zinc composite under green conditions. Meanwhile, this zinc catalyst could be easily recovered and reused for at least five times.
Activated charcoal-mediated synthesis of chalcones catalyzed by NaOH in water
Tanemura, Kiyoshi,Rohand, Taoufik
supporting information, (2021/02/27)
A variety of chalcones were synthesized in good yields by the activated charcoal-mediated aldol reactions between benzaldehydes and acetophenones catalyzed by NaOH in water. 2,6-Bis((E)-benzylidene)cyclohexan-1-ones were prepared by the aldol reactions between benzaldehydes and cyclohexanone. Activated charcoal could be recycled five times without the significant decrease of yields.
Crystal engineering with pyrazolyl-thiazole derivatives: Structure-directing role of π-stacking and σ-hole interactions
Ahmed, Muhammad Naeem,Madni, Murtaza,Anjum, Shaista,Andleeb, Saiqa,Hameed, Shahid,Khan, Abdul Majeed,Ashfaq, Muhammad,Tahir, Muhammad Nawaz,Gil, Diego M.,Frontera, Antonio
, p. 3276 - 3287 (2021/05/17)
The synthesis and X-ray characterization of 1-(2-(3-(4-bromophenyl)-5-(4-methoxyphenyl)-4,5-dihydro-1H-pyrazol-1-yl)-4-methylthiazol-5-yl)ethanone (7), ethyl 2-(5-(4-bromophenyl)-3-(4-chlorophenyl)-4,5-dihydropyrazol-1-yl)thiazole-4-carboxylate (8) and 2-(5-(4-chlorophenyl)-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl)-N′-(2-hydroxy-3-methoxybenzylidene)thiazole-4-carbohydrazide (10) are described in this manuscript. The structure-directing role of a variety of noncovalent interactions has been analyzed energetically using DFT calculations and Hirshfeld surface analysis. Moreover, the existence and importance of halogen and chalcogen bonding interactions have been analyzed by using the quantum theory of atoms in molecules and the noncovalent interaction index (NCIplot).
Iridium and copper supported on silicon dioxide as chemoselective catalysts for dehydrogenation and borrowing hydrogen reactions
Zhu, Guanxin,Duan, Zheng-Chao,Zhu, Haiyan,Qi, Minghui,Wang, Dawei
, (2021/04/02)
High active ligand usually plays an important role during catalysis and synthesis chemistry. A new and efficient benzotriazole-pyridinyl-silane ligand (BPS) was designed, and the corresponding iridium and copper catalysts were synthesized and thoroughly characterized by means of EDS, TEM, and XPS. The resulting iridium composite revealed excellent catalytic activity for the reaction of tert-butanesulfinamide with benzyl alcohols, while copper catalyst could realize the synthesis of unsaturated carbonyl compounds through the reaction of benzyl alcohols with ketones. This provided an efficient method for selective synthesis of unsaturated carbonyl compounds from benzyl alcohols and ketones in high yields with good recovery performance.
Potassium Natural Asphalt Sulfonate (K-NAS): Synthesis and characterization as a new recyclable solid basic nanocatalyst and its application in the formation of carbon–carbon bonds
Falah, Saeid,Soleiman-Beigi, Mohammad,Kohzadi, Homa
, (2020/07/06)
In this research, we synthesized and characterized a new heterogeneous basic nanocatalyst and its catalytic application was studied in the Claisen-Schmidt and Knoevenagel condensations. In order to prepare this nanocatalyst, first, the Iranian natural asphalt was sulfonated with the concentrated sulfuric acid and then, converted to the potassium natural asphalt sulfonate (K-NAS). In order to characterization of the nanocatalyst, used of FT-IR spectroscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), inductively coupled plasma (ICP) and thermogravimetric analysis (TGA) techniques. This new basic heterogeneous nanocatalyst have advantages such as being eco-friendly, huge specific surface area, high reactivity and recyclability.
A Convenient One-Pot Synthesis of Chalcones and Their Derivatives and Their Antimicrobial Activity
Salotra,Utreja,Sharma
, p. 2207 - 2211 (2021/02/09)
Abstract: A series of chalcones were synthesized by base-catalyzed Clasien-Schmidtcondensation of substituted benzaldehydes and substituted acetophenones at roomtemperature. The addition of hydrazine hydrate and hydroxylamine hydrochlorideacross the double bond of the obtained chalcones gave pyrazole and isoxazolederivatives, respectively. All the synthesized compounds were characterized by1H and 13C NMR andFT-IR spectroscopy and screened for their in vitro antimicrobial activityagainst two bacterial strains, Pseudomonasaeruginosa and Pseudomonasoryzihabitans using Ciprofloxacin as standard drug.1-(2-Methoxyphenyl)-3-phenylprop-2-en-1-one and1-(4-chlorophenyl)-3-phenylprop-2-en-1-one showed significant activity againstboth bacterial strains and hence proved to be potent antimicrobialagents.
Tuning the Product Selectivity of the α-Alkylation of Ketones with Primary Alcohols using Oxidized Titanium Nitride Photocatalysts and Visible Light
Li, Peifeng,Su, Haijia,Xiao, Gang,Zhao, Yilin
, p. 3640 - 3649 (2020/04/09)
The direct α-alkylation of ketones with alcohol to synthesize important α-alkylated ketones and enones is an attractive procedure for C-C bond formation. High reaction temperatures are always needed for heterogeneous catalysis using non-noble metals, and switching product selectivity in one catalysis system remains a great challenge. In the present study, a visible-light-driven procedure for this reaction is proposed, using oxidized TiN photocatalysts under mild conditions, whereby the product selectivity can be well-tuned. Oxidized TiN photocatalysts with tunable surface N/O ratios were successfully synthesized through the facile and flexible thermal oxidation treatment of low-cost TiN nanopowder. The α-alkylation of acetophenone with benzyl alcohol to form the two important compounds chalcone and dihydrochalcone occurred even at room temperature and almost complete conversion was achieved at 100 °C under visible light. The proportion of the two products can be well-tuned by switching the surface N/O ratio of the synthesized photocatalysts. Visible light is demonstrated to affect the surface N/O ratio of the photocatalysts and contribute to tuning the product selectivity. Light intensity and action spectrum study proves that the generation of energetic charge carriers results in the observed activities under visible light, based on interband transitions of TiN or the ligand-to-metal charge transfer (LMCT) effect of the surface complex formed on TiO2. Thermal energy can be coupled with light energy within this photocatalytic system, which will facilitate the full use of solar energy. Different sequential reaction mechanisms on TiN and TiO2 are proposed to be responsible for the tunable product selectivity. The wide reaction scope, the fine conversion at a low light intensity, and the favorable reusability of photocatalysts prove the great application potential of this visible-light-driven procedure for the α-alkylation of ketones with primary alcohols.
Hydroxyl- and Halogen-containing Chalcones for the Inhibition of LPS-stimulated ROS Production in RAW 264.7 Macrophages: Design, Synthesis and Structure–Activity Relationship Study
Shrestha, Aarajana,Shrestha, Aastha,Park, Pil-Hoon,Lee, Eung-Seok
, p. 729 - 734 (2019/07/19)
Oxidative stress due to overproduction of reactive oxygen species (ROS) plays a major role in inflammation, cancer, and neurodegenerative disorders. In this study, 60 chalcone derivatives with fluorine (F), trifluoromethyl (CF3), trifluoromethoxy (OCF3), chlorine (Cl), and bromine (Br) in ring A and with or without hydroxy (OH) in ring B were designed, synthesized, and screened for inhibitory activity against lipopolysaccharide (LPS)-stimulated ROS production in RAW 264.7 macrophages. Structure–activity relationship study revealed the importance of a hydroxyl moiety in ring B for enhancing inhibitory activity of ROS production. Furthermore, a hydroxyl group at the ortho-position is more essential for inhibition of ROS production followed by meta- and para-positions. Among all, compound 27 that contains para-chlorine moiety in ring A and ortho-hydroxy in ring B displayed the strongest inhibitory activity (IC50 = 3.42 μM) against LPS-stimulated ROS production in RAW264.7 macrophages.
Naphtho[2,3-: B] furan-4,9-dione synthesis via palladium-catalyzed reverse hydrogenolysis
Li, Jimei,Zhang, Jie,Li, Mingfei,Zhang, Chenyang,Yuan, Yongkun,Liu, Renhua
supporting information, p. 2348 - 2351 (2019/02/27)
A reverse hydrogenolysis process has been developed for two-site coupling of 2-hydroxy-1,4-naphthoquinones with olefins to produce naphtha[2,3-b]furan-4,9-diones and hydrogen (H2). The reaction is catalyzed by commercially available Pd/C without oxidants and hydrogen acceptors, thereby providing an intrinsically waste-free approach for the synthesis of functionalized and potentially biologically relevant naphtha[2,3-b]furan-4,9-diones.
Application of Polyphosphoric Acid-Mediated Acyl Migration for Regiospecific Synthesis of Diverse 2-Acylpyrroles from Chalcones
Kumar, Togiti Uday,Thigulla, Yadagiri,Rangan, Krishnan,Bhattacharya, Anupam
supporting information, p. 1283 - 1290 (2019/03/07)
A metal-free approach for the synthesis of 2-acylpyrroles is reported in this paper. Synthesis of the target molecule started from chalcones and was carried out in two steps. Initial step involved the conversion of chalcones to corresponding 4-substituted-3-acylpyrroles by reaction with TosMIC. In the subsequent step, target molecules were obtained in modest to good yields by polyphosphoric acid-mediated acyl rearrangement of 3-acylpyrroles to their 2-acyl congeners. The crucial final step was amenable to diverse substitutions on pyrrole ring. Preliminary experiment for the determination of mechanism indicated the involvement of acylium ion.