65246-39-1Relevant academic research and scientific papers
Regioselective Direct C2 Arylation of Indole, Benzothiophene and Benzofuran: Utilization of Reusable Pd NPs and NHC-Pd@MNPs Catalyst for C–H Activation Reaction
Hegde, Rajeev V.,Ong, Tiow-Gan,Ambre, Ram,Jadhav, Arvind H.,Patil, Siddappa A.,Dateer, Ramesh B.
, p. 1397 - 1405 (2020/10/02)
Abstract: A regioselective C2 arylation of indoles, benzothiophene and benzofuran without directing group has been accomplished using economically cheap Pd NPs and NHC-Pd@MNPs catalyst. The reusable catalyst is efficiently employed to access C2 arylated heterocycles in good to excellent yield. The reusability of the catalyst is studied up to five cycles and a gram-scale synthesis has been achieved. The reaction mechanism is well supported by control experiments and literature precedents. Grapic Abstract: [Figure not available: see fulltext.]
Room Temperature C-H Arylation of Benzofurans by Aryl Iodides
Mayhugh, Amy L.,Luscombe, Christine K.
supporting information, p. 7079 - 7082 (2021/09/18)
A robust method of room temperature direct arylation for benzofuran is reported. This discovery allows for mild arylation by commercially available aryl iodides with complete C-2 regioselectivity and tolerates a range of functional groups, including heat sensitive groups. Mechanistically, a Heck-type oxyarylation product from a direct arylation process is reported as a key piece of evidence for a carbopalladation intermediate.
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.
Synthesis of benzofurans from terminal alkynes and iodophenols catalyzed by recyclable palladium nanoparticles supported on N,O-dual doped hierarchical porous carbon under copper- and ligand-free conditions
Ji, Guijie,Duan, Yanan,Zhang, Shaochun,Yang, Yong
, p. 101 - 108 (2018/05/05)
We herein report that a stable and recyclable heterogeneous catalyst, consisting of Pd nanoparticles supported on N,O-dual doped hierarchical porous carbon derived from naturally available and renewable biomass-bamboo shoots, which allows for highly efficient one-pot tandem reaction of o-iodophenols with terminal alkynes to synthesize biologically active 2-benzofuran derivatives under copper- and ligand-free conditions. The catalyst performed superior catalytic performance compared with the analogous Pd/C and supported on other metal oxides under otherwise identical conditions. A broad set of aryl and alkyl terminal alkynes can be effectively coupled /cyclized with various o-iodophenols to afford their corresponding 2-benzofurans in good to high yields with good tolerance of multiple functional groups. Moreover, the catalyst showed good stability and could be reused several times without significant loss of activity.
CuI catalyzed domino coupling–cyclization of 2-iodo-phenols and 1-alkynes to the synthesis of 2-substituted benzo[b]furans/furo-pyridines
Chen, Ze-Pin,Zhou, Yi,Shui, Meng-Zhu,Liu, Feng
supporting information, p. 133 - 136 (2018/12/11)
CuI/proline-catalyzed coupling reaction of 2-iodo-phenols with terminal alkynes and the following cyclization process is carried out successively in DMSO at 80 °C. Under this tandem process, 2-substituted benzo[b]furans/furo-pyridines were synthesized in good to excellent yields with a great diversity.
Method for synthesizing benzofuran derivatives by copper-free ligand-free palladium catalyst
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Paragraph 0007; 0030-0037, (2019/11/13)
The invention relates to a synthesis method of benzofuran derivatives, in particular to a method for synthesizing the benzofuran derivatives by a copper-free ligand-free palladium catalyst. In the presence of K3PO4 solid and a DMF solvent, a compound 1 an
Transition-metal-free base catalyzed intramolecular cyclization of 2-ynylphenols for efficient and facile synthesis of 2-substituted benzo[b]furans
Liu, Yong,Lu, Tao,Tang, Wei-Fang,Gao, Jian
, p. 28637 - 28641 (2018/08/29)
A transition-metal-free base catalyzed intramolecular cyclization of 2-ynylphenols was developed for the facile synthesis of 2-substituted benzo[b]furans. Various 2-aryl and 2-alkyl substituted benzo[b]furans can be obtained with good to excellent yields
Aerobic, Metal-Free, and Catalytic Dehydrogenative Coupling of Heterocycles: En Route to Hedgehog Signaling Pathway Inhibitors
Bering, Luis,Paulussen, Felix M.,Antonchick, Andrey P.
supporting information, p. 1978 - 1981 (2018/04/16)
The nitrosonium ion-catalyzed dehydrogenative coupling of heteroarenes under mild reaction conditions is reported. The developed method utilizes ambient molecular oxygen as a terminal oxidant, and only water is produced as byproduct. Dehydrogenative coupl
Impregnated palladium on magnetite as catalyst for direct arylation of heterocycles
Cano, Rafael,Pérez, Juana M.,Ramón, Diego J.,McGlacken, Gerard P.
, p. 1043 - 1050 (2016/07/06)
Palladium impregnated on magnetite is an efficient, cheap and easy to prepare catalyst for the direct arylation of heterocycles. Good yields are afforded under relatively mild conditions and a broad substrate scope is evident. The catalyst is regioselective in many cases, affording arylated products, at the C2- or C3-position (depending of the heterocycle used). The methodology can be extended to prepare chromenes through an intramolecular direct arylation reaction. Some evidence is provided for two catalyst deactivation pathways, which prevents efficient recycling.
N-Heterocyclic Carbene-Palladium(II)-1-Methylimidazole Complex Catalyzed Direct C-H Bond Arylation of Benzo[b]furans with Aryl Chlorides
Yin, Shun-Chao,Zhou, Quan,Zhao, Xiao-Yun,Shao, Li-Xiong
, p. 8916 - 8921 (2015/09/15)
The first example of sole direct C-H bond arylation of benzo[b]furans with aryl chlorides was achieved catalyzed by a well-defined NHC-Pd(II)-Im complex. Under the suitable conditions, all reactions involving kinds of benzo[b]furans and (hetero)aryl chlor
