5328-73-4Relevant academic research and scientific papers
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.
Rapid umpolung Michael addition of isatin N, N ′-cyclic azomethine imine 1,3-dipoles with chalcones
Yue, Guizhou,Jiang, Dan,Dou, Zhengjie,Li, Sicheng,Feng, Juhua,Zhang, Li,Chen, Huabao,Yang, Chunping,Yin, Zhongqiong,Song, Xu,Liang, Xiaoxia,Wang, Xianxiang,Lu, Cuifen
supporting information, p. 11712 - 11718 (2021/07/12)
The umpolung Michael addition of isatin N,N′-cyclic azomethine imine 1,3-dipoles with chalcones is reported. The reaction could be finished within a very short time (0.3-2 min), with 3,3-disubstituted oxindole derivatives obtained in moderate to excellent yields with promising dr values. Unusual Michael adducts were obtained in moderate to high yields (26-98%) with low to high diastereoselectivities (0.8: 1 to 8.5: 1 dr). All the synthesized compounds (3, 3′, 4, 5, 5′, 7, 7′, 9 and 9′) were well characterized by FTIR, NMR, and mass spectral analyses and further confirmed by the single-crystal X-ray diffraction analysis of compounds 3aa and 4n.
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.
Some thiocarbamoyl based novel anticathepsin agents
Kaur, Ravinder,Raghav, Neera
, (2020/09/16)
Cathepsins have emerged as important targets in various tissues degenerative disorders due to their involvement in degradation of extracellular matrices and endogenous protein turnover. Elevated cathepsins levels vis-à-vis decreased concentration of endogenous inhibitors has been reported at different diseased sites. The design and synthesis of specific potential anti-cathepsin agents is therefore of great significance. Most of potential anti-cathepsin agents developed have peptide based structures with an active warhead. Due to oral instability and immunogenic problems related to peptidyl inhibitors drift the synthesis and evaluation of non-peptide cathepsin inhibitors in last two decades. The present work provides a detailed structure activity relationship for developing potential non-peptide anticathepsin agents based on in-vitro inhibition studies of a library of synthesized thiocarbamoyl- non-peptide inhibitors.
Photoredox β-thiol-α-carbonylation of enones accompanied by unexpected Csp2-C(CO) bond cleavage
Du, Ding,Feng, Jie,Ma, Rui,Zhang, Beichen,Zhang, Kuili
supporting information, p. 7549 - 7553 (2020/10/13)
An olefinic difunctionalization method of enones was presented hereviaaerobic visible-light catalysis. A novel reactivity was showcased in conjunction with the selective Csp2-C(CO) bond activation of enones, which provided a convenient method for the preparation of various β-thiolated-α-functionalized compounds. Moreover, the preliminary investigation of the mechanism indicated that a β-peroxysulfide intermediate was formed under the promotion of visible light under an oxygen atmosphere, which finally induced the unexpected C-C bond cleavage.
Diversified Transformations of Tetrahydroindolizines to Construct Chiral 3-Arylindolizines and Dicarbofunctionalized 1,5-Diketones
Feng, Xiaoming,He, Qianwen,Liu, Xiaohua,Pan, Chenjing,Su, Zhishan,Wu, Zhikun,Zhang, Dong,Zhou, Yuqiao
supporting information, p. 15975 - 15985 (2020/10/18)
Enantioselective diverse synthesis of a small-molecule collection with structural and functional similarities or differences in an efficient manner is an appealing but formidable challenge. Asymmetric preparation and branching transformations of tetrahydroindolizines in succession present a useful approach to the construction of N-heterocycle-containing scaffolds with functional group, and stereochemical diversity. Herein, we report a breakthrough toward this end via an initial diastereo- A nd enantioselective [3 + 2] cycloaddition between pyridinium ylides and enones, following diversified sequential transformations. Chiral N,N′-dioxide-earth metal complexes enable the generation of optically active tetrahydroindolizines in situ, across the strong background reaction for racemate-formation. In connection with deliberate sequential transformations, involving convenient rearomatic oxidation, and light-active aza-Norrish II rearrangement, the tetrahydroindolizine intermediates were converted into the final library including 3-arylindolizine derivatives and dicarbofunctionalized 1,5-dicarbonyl compounds. More importantly, the stereochemistry of four-stereogenic centered tetrahydroindolizine intermediates could be efficiently transferred into axial chirality in 3-arylindolizines and vicinal pyridyl and aryl substituted 1,5-diketones. In addition, densely functionalized cyclopropanes and bridged cyclic compounds were also discovered depending on the nature of the pyridinium ylides. Mechanism studies were involved to explain the stereochemistry during the reaction processes.
On the development of a nucleophilic methylthiolation methodology
Carvalho, Bernardo Basbaum Portinho De Puga,Amaral, Adriane Antonia Pereira,De Castro, Pedro P?ssa,Ferreira, Fernanda Cerqueira Moreira,Horta, Bruno Araújo Cautiero,Amarante, Giovanni Wilson
, p. 5420 - 5426 (2020/08/03)
Methylthiolation reactions are usually explored to access organosulfur compounds using methanethiol, an extremely flammable and toxic compound. Herein, methylthiomethyl esters were successfully applied as novel methylthiolation reagents in a low cost, transition-metal-free methodology. These reagents allowed the methylthiolation of a wide scope of chalcones, acyl ester derivatives and Morita-Baylis-Hillman acetates with good group tolerance, affording the methylthiolated products in moderate to excellent yields. The reaction mechanism was investigated through several control experiments, as well as by theoretical calculations employing Density Functional Theory. The results strongly support that a sulfurane and a sulfonium ylide appear as key intermediates and that a Pummerer type rearrangement is also crucial for the formation of this novel reagent. Furthermore, the methylthiolation mechanism is likely to proceed through the nucleophilic attack of the reagent, followed by an entropically favoured step involving the acetate attack to the positively charged species, then releasing the product. This journal is
Efficient catalytic performance of calcined tungstophosphoric acid for the Claisen-Schmidt condensation under solvent-free reaction
Alharthi, Abdulrahman I.
, p. 2579 - 2584 (2019/10/02)
Effect of calcination of tungstophosphoric acid catalyst was evaluated in terms of the synthesis of chalcone derivatives via Claisen-Schmidt condensation using the reaction of acetophenone and several substituted aldehydes. The catalyst was characterized before and after calcination by FT-IR to assess the effectiveness of the synthesis of the desired products. The calcined tungstophosphoric acid catalyst (HPW-CL) showed a better performance and high yield of Claisen-Schmidt products in a short period of time. It was also found out that the calcined tungstophosphoric acid provides a chemo selective, efficient and environmentally benign synthesis of chalcone in an excellent yield in a solvent-free system.
Environment Friendly Synthesis of N′-(1,3-Diphenylallylidene)-1-ethyl-7-methyl-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carbohydrazides: Crystal Structure and Their Anti-oxidant Potential
Mubarak, Shafaq,Zia-Ur-Rehman, Muhammad,Jamil, Nadia,Zaheer, Muhammad,Arshad, Muhammad Nadeem,Asiri, Abdullah Mohammad
, p. 1191 - 1200 (2019/11/19)
An environment friendly synthesis of novel hybrid pharmacophores derived from synergism of nalidixic acid and 1,3-diphenylprop-2-en-1-ones is described. Percent yield and reaction times of microwave assisted reactions have been compared with the reactions
1-Arylvinyl formats: A New CO Source and Ketone Source in Carbonylative Synthesis of Chalcone Derivatives
Qi, Xinxin,Lai, Ming,Zhu, Min-Jie,Peng, Jin-Bao,Ying, Jun,Wu, Xiao-Feng
, p. 5252 - 5255 (2019/02/25)
1-Arylvinyl formates as a kind of new CO surrogate have been explored for the first time. Most of the known CO precursors usually produce undesired residuals, which have to be removed. In this strategy, after CO release, the in situ generated acetophenones from 1-arylvinyl formates can be successfully applied as a good ketone source in the synthesis of chalcones with benzaldehydes via a palladium-catalyzed reductive carbonylation reaction. A variety of chalcones were isolated in satisfactory to good yields with good substrates compatibilities under mild conditions.
