18166-64-8Relevant academic research and scientific papers
Iron-catalyzed hydroaminocarbonylation of alkynes: Selective and efficient synthesis of primary α,β-unsaturated amides
Huang, Zijun,Jiang, Xiongwei,Lan, Donghui,Li, Yuehui,Pi, Shaofeng,Tan, Zhengde,Tang, Jia,Xie, Tianle,Yi, Bing,Zhang, Minmin
supporting information, (2022/02/22)
α,β-Unsaturated primary amides are important intermediates and building blocks in organic synthesis. Herein, we report a ligand-free iron-catalyzed hydroaminocarbonylation of alkynes using NH4HCO3 as the ammonia source, enabling the highly efficient and regioselective synthesis of linear α,β-unsaturated primary amides. Various aromatic and aliphatic alkynes are transformed into the desired linear α,β-unsaturated primary amides in good to excellent yields. Further studies show that using NH4HCO3 as the ammonia source is key to obtain good yields and selectivity. The utility of this route is demonstrated with the synthesis of linear α,β-unsaturated amides including vanilloid receptor-1 antagonist TRPV-1.
Phosphine-Functionalized Chitosan Microparticles as Support Materials for Palladium Nanoparticles in Heck Reactions
Biajoli, André F. P.,Fajardo, André R.,Lemos, Thalia S. A.,de Souza, Jaqueline F.
, (2022/01/11)
Herein, we investigated the activation and stabilization of Pd nanoparticles using microparticles of chitosan-functionalized with phosphine moieties. The catalytic activity of the prepared material was assessed in a series of Heck reactions, which demonst
Selective and facile synthesis of α,β-unsaturated nitriles and amides with N-hydroxyphthalimide as the nitrogen source
Yan, Yiyan,Xu, Xiaohe,Jie, Xiaokang,Cheng, Jingya,Bai, Renren,Shuai, Qi,Xie, Yuanyuan
supporting information, p. 2793 - 2796 (2018/06/25)
The direct conversion of α,β-unsaturated aldehydes to corresponding nitriles promoted by Pd(OAc)2 and phthalic acid which was hydrolyzed from N-hydroxyphthalimide (NHPI) has been disclosed. Additionally, it was found that when water was used as the solvent, α,β-unsaturated amides was obtained as the main products in good to excellent yields. It was first reported that NHPI was utilized as the nitrogen source to synthesize α,β-unsaturated nitriles and amides from aldehydes. Control experiment demonstrated that aldehydes undergo a process of oximation and dehydration to form nitriles and amides.
Copper(II)-Catalyzed Reactions of α-Keto Thioesters with Azides via C-C and C-S Bond Cleavages: Synthesis of N-Acylureas and Amides
Maity, Rajib,Naskar, Sandip,Das, Indrajit
, p. 2114 - 2124 (2018/02/23)
Cu(II)-catalyzed reaction of α-keto thioesters with trimethylsilyl azide (TMSN3) proceeds with the transformation of the thioester group into urea through C-C and C-S bond cleavages, constituting a practical and straightforward synthesis of N-acylureas. When diphenyl phosphoryl azide (DPPA) is used instead as the azide source in an aqueous environment, primary amides are formed via substitution of the thioester group. The reactions are proposed to proceed through Curtius rearrangement of the initially formed α-keto acyl azide to generate an acyl isocyanate intermediate, which reacts further with an additional amount of azide or water and rearranges to afford the corresponding products. To demonstrate the potentiality of the method, one-step syntheses of pivaloylurea and isovaleroylurea, displaying anticonvulsant activities, have been carried out.
Palladium-Catalyzed Regioselective Hydroaminocarbonylation of Alkynes to α,β-Unsaturated Primary Amides with Ammonium Chloride
Ji, Xiaolei,Gao, Bao,Zhou, Xibing,Liu, Zongjian,Huang, Hanmin
, p. 10134 - 10141 (2018/07/09)
α,β-Unsaturated primary amides have found numerous applications in drug development, organic materials, and polymer sciences. However, the catalytic synthesis of α,β-unsaturated primary amides via carbonylation of alkynes has long been an elusive endeavor. Here, we report a novel palladium-catalyzed hydroaminocarbonylation of alkynes with NH4Cl as the amine source, enabling the highly chemo- and regioselective synthesis of α,β-unsaturated primary amides. A variety of alkynes, including aromatic alkynes, aliphatic alkynes, terminal alkynes, internal alkynes, as well as diynes with various functional groups, react well. The method turns the parasitic noncoordination ability of ammonium salts into a strategic advantage, enabling the gram-scale reaction to be performed in the presence of 0.05 mol % of catalyst with excellent selectivity.
Synthesis and biological evaluation of (E)-cinnamic acid, (E)-2-styrylthiazole and (E)-2-[2-(naphthalen-1-yl)vinyl]thiazole derivatives
Olawode, Emmanuel O.,Tandlich, Roman,Prinsloo, Earl,Isaacs, Michelle,Hoppe, Heinrich,Seldon, Ronnett,Warner, Digby F.,Steenkamp, Vanessa,Kaye, Perry T.
, p. 284 - 296 (2018/03/09)
Cinnamyl- and thiazole-based compounds have been shown to exhibit diverse medicinal properties and a series of twelve (E)-2-styrylthiazole and (E)-2-[(naphthalen-1-yl)vinyl]thiazole derivatives, which are conjugates of both systems and which satisfy the "Lipinski rule of 5", have been synthesised and subjected to in vitro biological screening. While insignificant inhibition (60-98% viability at 10 μM) of HeLa (cervical cancer) cells was noted, all five of the (E)-2-[naphthalen-1- yl)vinyl]thiazole derivatives proved remarkably active against SH-SY5Y (neuroblastoma) cells with IC50 values ranging from 2.09 to 8.64 μM. Two of the seven (E)-2-styrylthiazoles were found to be moderately active (with IC50 values of 10.8 and 11.7 mM), whereas the remaining five analogues exhibit significant proliferation of SH-SY5Y cells (with IC50 values of 180-1000 mM). The results warrant further studies on the effects of styrylthiazoles on the differentiation and extension of SH-SY5Y cells in order to assess their activity in neurological degenerative diseases.
Palladium(II) complexes with a phosphino-oxime ligand: Synthesis, structure and applications to the catalytic rearrangement and dehydration of aldoximes
Menéndez-Rodríguez, Lucía,Tomás-Mendivil, Eder,Francos, Javier,Nájera, Carmen,Crochet, Pascale,Cadierno, Victorio
, p. 3754 - 3761 (2015/07/01)
The treatment of [PdCl2(COD)] (COD = 1,5-cyclooctadiene) with 1 and 2 equivalents of 2-(diphenylphosphino)benzaldehyde oxime in dichloromethane at room temperature led to the selective formation of [PdCl2{κ2-(P,N)-2-Ph2PC6H4CHNOH}] (1) and [Pd{κ2-(P,N)-2-Ph2PC6H4CHNOH}2][Cl]2 (2), respectively, which represent the first examples of Pd(II) complexes containing a phosphino-oxime ligand. These compounds, whose structures were fully confirmed by X-ray diffraction methods, were active in the catalytic rearrangement of aldoximes. In particular, using 5 mol% complex 1, a large variety of aldoximes could be cleanly converted into the corresponding primary amides at 100 °C, employing water as solvent and without the assistance of any cocatalyst. Palladium nanoparticles are the active species in the rearrangement process. In addition, when the same reactions were performed employing acetonitrile as solvent, selective dehydration of the aldoximes to form the respective nitriles was observed. For comparative purposes, the catalytic behaviour of an oxime-derived palladacyclic complex has also been briefly evaluated.
Optimization and Evaluation of 5-Styryl-Oxathiazol-2-one Mycobacterium tuberculosis Proteasome Inhibitors as Potential Antitubercular Agents
Russo, Francesco,Gising, Johan,?kerbladh, Linda,Roos, Annette K.,Naworyta, Agata,Mowbray, Sherry L.,Sokolowski, Anders,Henderson, Ian,Alling, Torey,Bailey, Mai A.,Files, Megan,Parish, Tanya,Karlén, Anders,Larhed, Mats
, p. 342 - 362 (2015/06/30)
This is the first report of 5-styryl-oxathiazol-2-ones as inhibitors of the Mycobacterium tuberculosis (Mtb) proteasome. As part of the study, the structure-activity relationship of oxathiazolones as Mtb proteasome inhibitors has been investigated. Furthermore, the prepared compounds displayed a good selectivity profile for Mtb compared to the human proteasome. The 5-styryl-oxathiazol-2-one inhibitors identified showed little activity against replicating Mtb, but were rapidly bactericidal against nonreplicating bacteria. (E)-5-(4-Chlorostyryl)-1,3,4-oxathiazol-2-one) was most effective, reducing the colony-forming units (CFU)/mL below the detection limit in only seven days at all concentrations tested. The results suggest that this new class of Mtb proteasome inhibitors has the potential to be further developed into novel antitubercular agents for synergistic combination therapies with existing drugs.
Thiazolyl-phosphine hydrochloride salts: Effective auxiliary ligands for ruthenium-catalyzed nitrile hydration reactions and related amide bond forming processes in water
Garcia-Alvarez, Rocio,Zablocka, Maria,Crochet, Pascale,Duhayon, Carine,Majoral, Jean-Pierre,Cadierno, Victorio
, p. 2447 - 2456 (2013/09/12)
A series of water-soluble N-protonated thiazolyl-phosphine hydrochloride salts have been synthesized and coordinated to the ruthenium(ii) fragment [RuCl2(η6-p-cymene)]. The resulting complexes were evaluated as potential catalysts for the selective hydration of nitriles to primary amides in environmentally friendly aqueous medium. The best results in terms of activity were achieved when tris(5-(2-aminothiazolyl))phosphine trihydrochloride was used as ligand. Using the Ru(ii) complex 9 derived from this salt (3 mol%), the catalytic reactions proceeded cleanly in pure water at 100 °C without the assistance of any additive, affording the desired amides in high yields (>78%) after short reaction periods (0.5-7 h). The process was operative with both aromatic, heteroaromatic, α,β-unsaturated and aliphatic nitriles, and tolerated several functional groups. The utility of 9 in promoting the formation of primary amides in water by catalytic rearrangement of aldoximes and direct coupling of aldehydes with NH2OH·HCl has also been demonstrated.
Heck arylation of conjugated alkenes with aryl bromides or chlorides catalyzed by immobilization of palladium in MCM-41
Yao, Fang,Liu, Jiaqin,Cai, Mingzhong
, p. 681 - 686 (2013/07/26)
A new 3-(2-aminoethylamino)propyl-functionalized MCM-41-immobilized palladium(II) complex [MCM-41-2N-PdCl2] was conveniently synthesized from commercially available and cheap 3-(2-aminoethylamino) propyltrimethoxysilane via immobilization on MCM-41, followed by reacting with palladium chloride. It was found that this heterogeneous palladium complex is a highly efficient catalyst for Heck arylation of conjugated alkenes with aryl bromides or chlorides using tetrabutylammonium bromide as additive and can be reused for at least six consecutive trials without any decreases in activity.
