68004-02-4Relevant academic research and scientific papers
Bimetallic Cooperative Catalysis for Decarbonylative Heteroarylation of Carboxylic Acids via C-O/C-H Coupling
Liu, Chengwei,Ji, Chong-Lei,Zhou, Tongliang,Hong, Xin,Szostak, Michal
supporting information, p. 10690 - 10699 (2021/04/09)
Cooperative bimetallic catalysis is a fundamental approach in modern synthetic chemistry. We report bimetallic cooperative catalysis for the direct decarbonylative heteroarylation of ubiquitous carboxylic acids via acyl C-O/C-H coupling. This novel catalytic system exploits the cooperative action of a copper catalyst and a palladium catalyst in decarbonylation, which enables highly chemoselective synthesis of important heterobiaryl motifs through the coupling of carboxylic acids with heteroarenes in the absence of prefunctionalization or directing groups. This cooperative decarbonylative method uses common carboxylic acids and shows a remarkably broad substrate scope (>70 examples), including late-stage modification of pharmaceuticals and streamlined synthesis of bioactive agents. Extensive mechanistic and computational studies were conducted to gain insight into the mechanism of the reaction. The key step involves intersection of the two catalytic cycles via transmetallation of the copper–aryl species with the palladium(II) intermediate generated by oxidative addition/decarbonylation.
Cu-Catalyzed Aerobic Oxidative Sulfuration/Annulation Approach to Thiazoles via Multiple Csp3-H Bond Cleavage
Wang, Xiaoyang,Qiu, Xu,Wei, Jialiang,Liu, Jianzhong,Song, Song,Wang, Wen,Jiao, Ning
supporting information, p. 2632 - 2636 (2018/05/22)
A novel and practical Cu-catalyzed aerobic oxidative synthesis of thiazoles was developed. This chemistry for the first time achieved thiazole construction from simple aldehydes, amines, and element sulfur through multiple Csp3-H bond cleavage processes. Molecular oxygen was used as a green oxidant in this oxidative protocol. The substrate scope is broad with the tolerance of aliphatic amines. The mechanistic study might promote the reaction design for a new sulfuration/annulation reaction with readily available element sulfur.
Facile Synthesis of 2,5-Disubstituted Thiazoles from Terminal Alkynes, Sulfonyl Azides, and Thionoesters
Miura, Tomoya,Funakoshi, Yuuta,Fujimoto, Yoshikazu,Nakahashi, Junki,Murakami, Masahiro
supporting information, p. 2454 - 2457 (2015/05/27)
A sequential procedure for the synthesis of 2,5-disubstituted thiazoles from terminal alkynes, sulfonyl azides, and thionoesters is reported. A copper(I)-catalyzed 1,3-dipolar cycloaddition of terminal alkynes with sulfonyl azides affords 1-sulfonyl-1,2,3-triazoles, which then react with thionoesters in the presence of a rhodium(II) catalyst. The resulting 3-sulfonyl-4-thiazolines subsequently aromatize into the corresponding 2,5-disubstituted thiazoles by elimination of the sulfonyl group. (Chemical Equation Presented).
Programmed synthesis of arylthiazoles through sequential C-H couplings
Tani, Satoshi,Uehara, Takahiro N.,Yamaguchi, Junichiro,Itami, Kenichiro
, p. 123 - 135 (2014/01/06)
A programmed synthesis of privileged arylthiazoles via sequential C-H couplings catalyzed by palladium or nickel catalysts has been accomplished. This versatile protocol can supply all possible arylthiazole substitution patterns (2-aryl, 4-aryl, 5-aryl, 2
Pd nanoparticle-silica nanotubes (Pd@SNTs) as an efficient catalyst for Suzuki-Miyaura coupling and sp2 C-H arylation in water
Park, Ginam,Lee, Sanghee,Son, Sang Jun,Shin, Seunghoon
supporting information, p. 3468 - 3473 (2013/12/04)
Silica nanotubes (SNTs) functionalized with Pd-NPs on the inner surface performed as efficient nano-reactors for C-C coupling in water; the nano-confinement offers minimized leaching of Pd and yet efficient mass transfer for Suzuki-Miyaura coupling and C-H arylation of thiazoles in water with very high TON.
Direct arylation of simple azoles catalyzed by 1,10-phenanthroline containing palladium complexes: An investigation of C4 arylation of azoles and the synthesis of triarylated azoles by sequential arylation
Shibahara, Fumitoshi,Yamaguchi, Eiji,Murai, Toshiaki
, p. 2680 - 2693 (2011/06/20)
Direct triarylation and sequential triarylation reactions of simple azoles catalyzed by [Pd(phen)2]PF6 are described. Simple azoles, such as N-methylimidazole, thiazole, and oxazole, were observed to undergo triaryaltion reactions even at their C4 positions when treated with aryl iodides in the presence of [Pd(phen)2]PF6 as a catalyst and a stoichiometric amount of Cs2CO3 in DMA at 150 °C. Using excess amounts of azoles, selective C5 monoarylation was achieved by using the same catalytic system. Subsequent efforts demonstrated that C5 arylated azoles undergo exclusive C2 arylation using [Pd(phen)2]PF6 as the catalyst with galvinoxyl as an additive. Finally, unprecedented C4 arylation reactions of 2,5-diaryl-azoles occur by using the new catalytic system to give the corresponding triarylated products in good to excellent yields. The results of mechanistic studies suggest that the C2 arylation process takes place by way of an electrophilic aromatic substitution (SEAr) palladation pathway, while arylation reactions at the C4 position occur via a SEAr palladation and/or radical mechanism. Finally, a concise, three-step synthesis of the Tie-2 Tyrosine Kinase Inhibitor has been executed starting with commercially available N-methylimidazole by a route that employs the new sequential arylation process.
General facile synthesis of 2,5-diarylheteropentalenes
Vachal, Petr,Toth, Leslie M.
, p. 7157 - 7161 (2007/10/03)
Palladium-catalyzed cross-coupling reactions of various heteropentalene derivatives were systematically studied. A general three-step synthesis of 2,5-diarylheteropentalenes involving two Suzuki or Negishi couplings and a regiospecific bromination was developed. Nonsymmetrical 2,5-diaryl-furans, thiophenes, pyrroles, 1,3-thiazoles, 1,3-oxazoles, 1,3,4-thiadiazoles, and 1,3,4-oxadiazoles were prepared in 31-67% isolated yield (three steps).
Facile synthesis of 2,5-diarylthiazoles via palladium-catalyzed tandem C-H substitutions. Design of tunable light emission and liquid crystalline characteristics
Mori, Atsunori,Sekiguchi, Akitoshi,Masui, Kentaro,Shimada, Tomohiro,Horie, Masaki,Osakada, Kohtaro,Kawamoto, Masuki,Ikeda, Tomiki
, p. 1700 - 1701 (2007/10/03)
A mild and regioselective C-H substitution reaction of thiazole by the catalysis of the palladium/copper system is found to proceed in the presence of tetrabutylammonium fluoride under mild conditions. Applying the new reaction, we synthesized various 2,5
