99846-56-7Relevant academic research and scientific papers
Pd-NHCs Enabled Suzuki-Miyaura Cross-Coupling of Arylhydrazines via C–N Bond Cleavage
Zeng, Xiao-Xiao,Li, Dong-Hui,Zhou, Zhen,Xu, Chang,Liu, Feng-Shou
supporting information, (2021/03/01)
We describe a highly efficient protocol for cross-coupling of phenylhydrazines with arylboronic acids by Pd-NHCs under aerobic reaction condition. A series of well-defined Pd-NHCs complexes were evaluated and the relationship between the structure and the catalytic properties was investigated. It was disclosed that the Pd-PEPPSI-IPr proved to be the robust precatalyst, providing access to a range of (hetero)biaryls in good to excellent yields.
Transition-Metal-Free Synthesis of Heterobiaryls through 1,2-Migration of Boronate Complex
Paul, Swagata,Das, Kanak Kanti,Manna, Samir,Panda, Santanu
supporting information, p. 1922 - 1927 (2020/02/04)
The synthesis of a diverse range of heterobiaryls has been achieved by a transition-metal-free sp2–sp2 cross-coupling strategy using lithiated heterocycle, aryl or heteroaryl boronic ester and an electrophilic halogen source. The construction of heterobiaryls was carried out through electrophilic activation of the aryl–heteroaryl boronate complex, which triggered 1,2-migration from boron to the carbon atom. Subsequent oxidation of the intermediate boronic ester afforded heterobiaryls in good yield. A comprehensive 11B NMR study has been conducted to support the mechanism. The cross coupling between two nucleophilic cross coupling partners without transition metals reveals a reliable manifold to procure heterobiaryls in good yields. Various heterocycles like furan, thiophene, benzofuran, benzothiophene, and indole are well tolerated. Finally, we have successfully demonstrated the gram scale synthesis of the intermediates for an anticancer drug and OLED material using our methodology.
(N-Heterocyclic carbene) ion-pair palladium complexes: Suzuki–Miyaura cross-coupling studies in neat water under mild conditions
Chen, Ming-Tsz,Lin, Yu-Hsuan,Jian, Kun-Han
, (2020/08/05)
The synthesis and characterization of a series of (N-heterocyclic carbene)PdCl3?(NMe3H)+ ion-pair complexes are presented. Applying the quaternary ammonium salt as the function with NHC–Pd(II) complexes yields the new ion-pair complexes. The NHC–Pd(II) ion-pair complexes work well by undergoing the Suzuki–Miyaura reaction with aryl chloride substrates in water under mild conditions in air at room temperature. Twenty products resulting from Suzuki–Miyaura coupling reactions carried out in the presence of the new NHC–Pd(II) ion-pair complex under mild optimal conditions were examined to determine the optimum yields.
Perylenequinonoid-catalyzed photoredox activation for the direct arylation of (het)arenes with sunlight
Zhang, Shiwei,Tang, Zhaocheng,Bao, Wenhao,Li, Jia,Guo, Baodang,Huang, Shuping,Zhang, Yan,Rao, Yijian
supporting information, p. 4364 - 4369 (2019/05/10)
Naturally occurring perylenequinonoid pigments (PQPs) have attracted considerable attention owing to their excellent properties of photosensitization. They have been widely investigated as an aspect of photophysics and photobiology. However, their applications in photocatalysis are yet to be explored. We report here that sunlight along with 1 mol% cercosporin, which is one of the perylenequinonoid pigments, catalyzes the direct C-H bond arylation of (het)arenes by a photoredox process with good regioselectivity and broad functional group compatibility. Furthermore, a gram-scale reaction with great conversions of substrates was achieved even by a cercosporin-containing supernatant without organic solvent extraction and purification after liquid fermentation. Thus we set up a bridge between microbial fermentation and organic photocatalysis for chemical reactions in a sustainable, environmentally friendly manner.
Accessing Heterobiaryls through Transition-Metal-Free C-H Functionalization
Banik, Ananya,Paira, Rupankar,Shaw, Bikash Kumar,Vijaykumar, Gonela,Mandal, Swadhin K.
, p. 3236 - 3244 (2018/03/23)
Herein we report a transition-metal-free synthetic protocol for heterobiaryls, one of the most important pharmacophores in the modern drug industry, employing a new multidonor phenalenyl (PLY)-based ligand. The current procedure offers a wide substrate scope (24 examples) with a low catalyst loading resulting in an excellent product yield (up to 95%). The reaction mechanism involves a single electron transfer (SET) from a phenalenyl-based radical to generate a reactive heteroaryl radical. To establish the mechanism, we have isolated the catalytically active SET initiator, characterizing by a magnetic study.
Non-Directed Cross-Dehydrogenative (Hetero)arylation of Allylic C(sp3)?H bonds enabled by C?H Activation
Lerchen, Andreas,Knecht, Tobias,Koy, Maximilian,Ernst, Johannes B.,Bergander, Klaus,Daniliuc, Constantin G.,Glorius, Frank
supporting information, p. 15248 - 15252 (2018/10/20)
Herein, we report the selective, non-directed and cross-dehydrogenative coupling of allylic C(sp3)?H bonds with C(sp2)?H bonds of (hetero)arenes. The methodology employs olefins and (hetero)arenes which are abundantly available chemical feedstocks, and could be applied in late-stage functionalization reactions of pharmaceuticals. Furthermore, the system exclusively delivers the allylic C?C coupling products highlighting the preservation of the olefin substitution pattern for further derivatization.
Gram-scale synthesis of aligned C3N4-polypyrrole heterojunction aerogels with tunable band structures as efficient visible and near infrared light-driven metal-free photocatalysts
Liu, Jian,Wang, Hao,Bai, Jinwei,Li, Tianrong,Yang, Yanmei,Peng, Yong,Wang, Baodui
, p. 24920 - 24928 (2017/12/15)
The assembly of aligned porous materials from simple building blocks is of widespread interest for engineering materials with enhanced and synergistic properties. To date, however, how to develop 3D heterojunction aerogels with aligned porosity based on 2D semiconductor materials and 1D conducting polymers for solar energy conversion in the visible and near-infrared (NIR) light region remains a significant challenge. Here a new class of gram-scale 3D aligned heterojunction aerogels of polypyrrole (PPy)/C3N4 nanosheets (NSs) were designed and synthesized by directional freezing of polypyrrole (PPy)/polyvinyl alcohol (PVA) and C3N4 NS aqueous suspension. The synthesis of aligned C3N4-PPy heterojunction aerogels can be achieved on a large scale. The formed aerogel expresses stable and uniform dispersion of the two building blocks, long-range channel aligned structures along the whole monolithic sample, and additional special complementary optical properties between PPy and C3N4 NSs. Based on the above unique structure and optical properties, this novel metal-free heterojunction aerogel exhibits excellent photocatalytic activity and long-term stability for direct arylation of heteroaromatics under visible and near infrared (NIR) light irradiation at room temperature, far exceeding those of the single- and two-component systems. Our work therefore not only provides a new approach to obtain aligned heterojunction aerogels based on metal free semiconductors but also paves a way to develop gram-scale aerogels as a new type of highly efficient visible and NIR light induced heterogeneous photocatalyst.
Effect on orthometallation of NHC palladium complexes toward the catalytic activity studies in Suzuki coupling reaction
Chen, Ming-Tsz,Kao, Zing-Lun
supporting information, p. 16394 - 16398 (2017/12/15)
Herein, we report an approach to improve catalytic activity for cross-coupling reactions. N-Heterocyclic carbene (NHC) palladium complexes bearing a nitrogen-based ligand without orthometallation complexes show remarkable activities in Suzuki coupling reaction than orthometallation. Aryl chlorides examples employed in air and ambient temperature in Suzuki coupling reaction to reach completion within few minutes.
2-Aryl-indenylphosphine ligands: Design, synthesis and application in Pd-catalyzed Suzuki-Miyaura coupling reactions
Lian, Ze-Yu,Yuan, Jia,Yan, Meng-Qi,Liu, Yan,Luo, Xue,Wu, Qing-Guo,Liu, Sheng-Hua,Chen, Jian,Zhu, Xiao-Lei,Yu, Guang-Ao
supporting information, p. 10090 - 10094 (2016/11/06)
A focused library of phosphine ligands was constructed for structural optimization. The catalyst can be used to perform the Suzuki-Miyaura cross-coupling reaction of aryl and heteroaryl chlorides.
Biarylalkyl Carboxylic Acid Derivatives as Novel Antischistosomal Agents
M?der, Patrick,Blohm, Ariane S.,Quack, Thomas,Lange-Grünweller, Kerstin,Grünweller, Arnold,Hartmann, Roland K.,Grevelding, Christoph G.,Schlitzer, Martin
supporting information, p. 1459 - 1468 (2016/07/16)
Parasitic platyhelminths are responsible for serious infectious diseases, such as schistosomiasis, which affect humans as well as animals across vast regions of the world. The drug arsenal available for the treatment of these diseases is limited; for example, praziquantel is the only drug currently used to treat ≥240 million people each year infected with Schistosoma spp., and there is justified concern about the emergence of drug resistance. In this study, we screened biarylalkyl carboxylic acid derivatives for their antischistosomal activity against S. mansoni. These compounds showed significant influence on egg production, pairing stability, and vitality. Tegumental lesions or gut dilatation was also observed. Substitution of the terminal phenyl residue in the biaryl scaffold with a 3-hydroxy moiety and derivatization of the terminal carboxylic acid scaffold with carboxamides yielded compounds that displayed significant antischistosomal activity at concentrations as low as 10 μm with satisfying cytotoxicity values. The present study provides detailed insight into the structure–activity relationships of biarylalkyl carboxylic acid derivatives and thereby paves the way for a new drug-hit moiety for fighting schistosomiasis.
