4874-85-5Relevant academic research and scientific papers
Synthesis of new Copper Catalyst with Pyrazole Based Tridentate Ligand and Study of Its Activity for Azide Alkyne Coupling
Rajeswari, Panneer Selvam,Nagarajan, Rajendran,P, Sujith K,Emmanuvel, Lourdusamy
supporting information, (2020/12/03)
Synthesis of new copper catalyst with pyrazole based tridentate ligand and study of its activity for azide alkyne coupling were investigated by researchers. To a solution of acetyl acetone (2.002 g, 20 mmol), 2- nitrophenylhydrazine in ethanol was added five drops of con. HCl and heated at 50° for 1 hour. After confirming the formation of 3, 5-dimethyl-1-(2-nitrophenyl)- 1H-pyrazole by TLC, ice cooled water was added in to the reaction mixture. The precipitate was filtered, washed with water and then hexane. The product formed as yellow precipitate, that precipitate had been filtered by normal filter paper. The product was recrystallized in ethanol. For synthesis, was suspended in 6 mL of deionized and stirred for 4 h until a clear solution was obtained in 50 ml round bottom flask Cu(OAc) 2. The reaction mixture was diluted with water, filtered, washed sequentially with water, methanol and n-hexane. Then dark greenish blue color crystal were formed and used for the reactions. The solid was crystallized in CH2Cl2 to get crystal whose structure was confirmed by single crystal XRD.
Mono- and Di-Mesoionic Carbene-Boranes: Synthesis, Structures and Utility as Reducing Agents
Stein, Felix,Kirsch, Marius,Beerhues, Julia,Albold, Uta,Sarkar, Biprajit
, p. 2417 - 2424 (2021/06/17)
Mesoionic carbenes (MIC) of the 1,2,3-triazol-5-ylidene type are currently popular ligands in organometallic chemistry. Their use in main group chemistry has been rather limited. In this contribution we present mono- and di-MIC-boranes with MICs based on triazolylidenes. The synthesis involves in-situ deprotonation of the corresponding triazolium salts and their reaction with boranes to form the desired compounds. Whereas this reaction route worked well for all triazolium salts derived from the 1,4-regioisomer of the triazoles, for the methlyene-bridged bi-triazolium salt derived from a 1,5-substiuted triazole, we observed the unexpected decomposition of the bi-triazolium and the formation of a triazole-borane with a new N?B bond. All compounds were characterized via multinuclear NMR spectroscopy, mass spectrometry, and single crystal X-ray diffraction. Furthermore, the MIC-boranes were used as reducing agents for the reduction of the C=O of aldehydes to the corresponding alcohols.
Novel synthesis of 1,5-disubstituted-1,2,3-triazolines catalysed by Zepto magnetic microspheres under the influence of a rotating magnetic field
Sharma, Priyanka,Vallabhapurapu, Srinivasu V.,Ho, Wei H.,Hemmaragala, Nanjundaswamy M.
, p. 163 - 168 (2019/03/05)
The novel reactor has been designed to perform chemical reactions under the influence of a magnetic field generated by alternating magnetic poles as a function of time. The system was successfully employed to synthesize a series of 1,5-disubstituted-1,2,3-triazolines via the regioselective [3 + 2] cycloaddition reactions between alkyl/aryl azides and nitroolefins catalysed by Zepto (para magnetic ultra-blue carboxy functionalized) microspheres (bead diameter 2.5 μm). All of the reactions went smoothly without any adverse effect on nitro, cyano, thienyl, hydroxy, halogens, and ether functions at 25 ± 2 °C and afforded 82%-99% pure products at a magnetic field of 18.99 mT and an exposure time of 180-240 min. The influence of the magnetic force exerted on the magnetic materials was found to enhance the catalytic activity of microspheres. The catalyst could easily be separated by simple centrifugation, which could be reused for at least 15 runs with no loss in activity.
Transition-metal-free regioselective construction of 1,5-diaryl-1,2,3-triazoles through dehydrative cycloaddition of alcohols with aryl azides mediated by SO2F2
Zhang, Xu,Rakesh,Qin, Hua-Li
, p. 2845 - 2848 (2019/03/06)
A novel, simple and practical method for mild, efficient, cost-effective and regioselective synthesis of highly valuable 1,5-diaryl-1,2,3-triazoles was achieved through dehydrative annulation of readily available alcohols with aryl azides. The reaction proceeded at room temperature, without any metal catalysts, exhibiting excellent compatibility to a large variety of functional groups (>50 examples), resulting in up to quantitative yields. 2019
Regioselective synthesis of 1,5-disubstituted 1,2,3-triazoles by 1,3-dipolar cycloaddition: Role of Er(OTf)3, ionic liquid and water
Maiuolo, Loredana,Russo, Beatrice,Algieri, Vincenzo,Nardi, Monica,Di Gioia, Maria Luisa,Tallarida, Matteo Antonio,De Nino, Antonio
supporting information, p. 672 - 674 (2019/02/03)
A simple procedure to obtain 1,5-disubstituted 1,2,3-triazoles, using the Er(OTf)3/[mpy]OTf/H2O catalytic system is described. The reaction proceeds through an eliminative azide–olefin cycloaddition (EAOC) offering a highly regiosele
Copper-promoted Chan-Lam coupling between enaminones and aryl boronic acids
Duan, Xiyan,Liu, Ning,Liu, Kun,Song, Yakun,Wang, Jia,Mao, Xianhua,Xu, Weidong,Yang, Shijie,Li, Huixian,Ma, Junying
, p. 4187 - 4190 (2018/10/24)
A novel copper-promoted N-arylation of enaminones with aromatic boronic acids has been developed, which provides an efficient way to synthesize N-aryl enaminones with a broad substrate scope and excellent functional group compatibility. The N-aryl enaminones could be converted into a series of highly valuable building blocks and bioactive compounds. Notably, in comparison with traditional methods, this alternative approach provides accesses to N-aryl enaminones bearing multiple aromatic rings.
Convergent synthesis of trifunctional molecules by three sequential azido-type-selective cycloadditions
Yoshida, Suguru,Kanno, Kimiyuki,Kii, Isao,Misawa, Yoshihiro,Hagiwara, Masatoshi,Hosoya, Takamitsu
, p. 3705 - 3708 (2018/04/17)
A facile strategy for the synthesis of trifunctional molecules involving three sequential selective triazole-forming reactions is proposed. This method exploits three kinds of mechanistically different azido-type-selective cycloadditions. Three different azidophiles could be efficiently connected to a triazido platform molecule with three types of azido groups in a consecutive manner, which rendered a practical trifunctional molecule readily available.
Copper-catalyzed decarboxylative regioselective synthesis of 1,5-disubstituted 1,2,3-triazoles
Kumar, Navaneet,Ansari, Mohd Yeshab,Kant, Ruchir,Kumar, Atul
supporting information, p. 2627 - 2630 (2018/03/21)
A copper-catalyzed decarboxylative regioselective protocol for the synthesis of 1,5-disubstituted 1,2,3-triazoles through direct annulation of cinnamic acids with aryl azides has been developed. This is the first example of 1,5-disubstituted 1,2,3-triazoles, under aerobic conditions using Cu(ii) as the catalyst, which were generally synthesized using a ruthenium(ii) catalyst. The simplicity and regioselectivity of this methodology, complementing to the classical CuAAC catalyzed the synthesis of 1,4-disubstituted 1,2,3-triazoles.
Design and applications of new phosphine-free tetradentate Pd-catalyst: Regioselective C–H activation on 1-substituted 1,2,3-triazoles and indoles(NH-Free)
Markandeya, Sarma V.,Renuka, Ch.,Lakshmi, Parvathi K.,Rajesh,Sridhar, Chidara,Babu, Korupolu Raghu
supporting information, p. 135 - 145 (2017/12/28)
This article describes the synthesis of a new phosphine free tetradentate Pd catalyst using dl-2,3-diaminopropionic acid. The complex was characterized by Mass, IR, and 1H NMR. The catalyst is air stable at room temperature and non-hygroscopic. Application of this new catalyst to regioselective C–H activation on 1-substituted 1,2,3-triazole and indoles with aryl iodides to get corresponding C-5 and C-2 arylated products with satisfactory yields. All the products were characterized by spectroscopic studies.
N-Heterocyclic carbene–copper complex supported on ionic liquid-modified graphene oxide: versatile catalyst for synthesis of (i) 1,2,3-triazole and (ii) propargylamine derivatives
Dabiri, Minoo,Alavioon, Seyed Iman,Movahed, Siyavash Kazemi
, p. 2463 - 2474 (2018/09/13)
A N-heterocyclic carbene–copper complex grafted on graphene oxide with an ionic liquid framework was prepared. The synthesis of (i) 1,2,3-triazole derivatives by ‘Click reaction’ and (ii) propargylamine derivatives by ‘A3 coupling reaction’ in
