33104-08-4Relevant academic research and scientific papers
Nickel-Catalyzed Intramolecular Nucleophilic Addition of Aryl Halides to Aryl Ketones for the Synthesis of Benzofuran Derivatives
Zhu, Xiao-Rui,Deng, Chen-Liang
, p. 1842 - 1848 (2021/02/09)
A nickel-catalyzed intramolecular nucleophilic addition reaction of aryl halides to aryl ketones for the formation of benzofuran derivatives has been developed. A number of substrates bearing electron-donating or electron-withdrawing groups were subjected to the standard reaction conditions, giving the corresponding products in moderate to good yields.
Synthesis of benzofurans from the cyclodehydration of α-phenoxy ketones mediated by Eaton’s reagent
Ma, Zhanwei,Zhou, Min,Ma, Lin,Zhang, Min
, p. 426 - 436 (2020/03/23)
Cyclodehydration of α-phenoxy ketones promoted by Eaton’s reagent (phosphorus pentoxide–methanesulfonic acid) is used to prepare 3-substituted or 2,3-disubstituted benzofurans with moderate to excellent yields under mild conditions. The method provides a facile access to benzofurans from readily available starting materials such as phenols and α-bromo ketones. The reaction is highly efficient, which is attributed to the good reactivity and fluidity of Eaton’s reagent. The reaction can be applied to prepare naphthofurans, furanocoumarins, benzothiophenes, and benzopyrans.
Mechanistic Insights into Rhenium-Catalyzed Regioselective C-Alkenylation of Phenols with Internal Alkynes
Murai, Masahito,Yamamoto, Masaki,Takai, Kazuhiko
supporting information, p. 15189 - 15197 (2019/11/16)
A (μ-aryloxo)rhenium complex was isolated and confirmed as a key precatalyst for rhenium-catalyzed ortho-alkenylation (C-alkenylation) of unprotected phenols with alkynes. The reaction exclusively provided ortho-alkenylphenols; the formation of para or multiply alkenylated phenols and hydrophenoxylation (O-alkenylation) products was not observed. Several mechanistic experiments excluded a classical Friedel–Crafts-type mechanism, leading to the proposed phenolic hydroxyl group assisted electrophilic alkenylation as the most plausible reaction mechanism. For this purpose, the use of rhenium, a metal between the early and late transition metals in the periodic table, was key for the activation of both the soft carbon–carbon triple bond of the alkyne and the hard oxygen atom of the phenol, at the same time. ortho-Selective alkenylation with allenes also provided the corresponding adducts with a substitution pattern different from that obtained by the addition reaction with alkynes.
Dehydrative condensation of carbonyls with non-acidic methylenes enabled by light: Synthesis of benzofurans
Liu, Wenbo,Chen, Ning,Yang, Xiaobo,Li, Lu,Li, Chao-Jun
supporting information, p. 13120 - 13123 (2016/11/09)
Condensation of carbonyls with non-acidic methylenes such as those adjacent to heteroatoms and allylic types to generate CC bonds is challenging but highly desirable. Inventing novel methods that can accomplish such condensations can enrich synthetic chemists' toolbox. Herein, we report a simple, clean, and high yielding protocol promoted by light to achieve condensation of non-acidic methylenes with carbonyls. As examples to demonstrate the power of this methodology, one class of ubiquitous and highly important heterocycles, i.e. benzofurans, were synthesized with broad functional group compatibility. Furthermore, intermolecular condensations were also briefly investigated.
The Pd-catalyzed synthesis of benzofused carbo- and heterocycles through carbene migratory insertion/carbopalladation cascades with tosylhydrazones
Paraja, Miguel,Carmen Pérez-Aguilar,Valdés, Carlos
, p. 16241 - 16243 (2015/11/10)
The Pd-catalyzed reaction between o-iodoallylbenzene and tosylhydrazones gives rise to indene derivatives through a process that involves a carbene migratory insertion followed by an intramolecular carbopalladation, with the formation of two C-C bonds on
Nickel-NHC-catalyzed cross-coupling of 2-methylsulfanylbenzofurans with alkyl grignard reagents
Baralle, Alexandre,Otsuka, Shinya,Guérin, Vincent,Murakami, Kei,Yorimitsu, Hideki,Osuka, Atsuhiro
supporting information, (2015/02/19)
NiCl2(PPh3)(IPr) catalyzes cross-coupling reactions of 2-methylsulfanylbenzofurans with alkyl Grignard reagents. Other nickel complexes such as NiCl2(dppe) failed to catalyze the same reaction. The alkylation is applicable to the synthesis of a couple of protein tyrosine phosphatase inhibitors, 3-(4-biphenylyl)-2-alkylbenzofurans.
Facile synthesis of benzofurans via copper-catalyzed aerobic oxidative cyclization of phenols and alkynes
Zeng, Wei,Wu, Wanqing,Jiang, Huanfeng,Huang, Liangbin,Sun, Yadong,Chen, Zhengwang,Li, Xianwei
supporting information, p. 6611 - 6613 (2013/07/26)
Regioselective synthesis of polysubstituted benzofurans using a copper catalyst and molecular oxygen from phenols and alkynes in a one-pot procedure has been reported. The transformation consists of a sequential nucleophilic addition of phenols to alkynes and oxidative cyclization. A wide variety of phenols and alkynes can be used in the same manner.
Indium triflate-catalyzed coupling between nitroalkenes and phenol/naphthols: A simple and direct synthesis of arenofurans by a cyclization reaction
Kundu, Dhiman,Samim, Md,Majee, Adinath,Hajra, Alakananda
supporting information; experimental part, p. 406 - 409 (2011/10/12)
An eye furan eye: A simple and efficient protocol for the synthesis of benzofuran and naphthofuran derivatives catalyzed by indium triflate was developed by coupling α,β-unsaturated nitroalkenes with phenol/naphthols. The present method provides arenofuran derivatives in one pot from readily available starting materials (DCE=1,2-dichloroethane; see scheme). Copyright
A simple approach to highly functionalized benzo[b]furans from phenols and aryl iodides via aryl propargyl ethers
Lingam, V.S. Prasada Rao,Vinodkumar, Ramanatham,Mukkanti, Khagga,Thomas, Abraham,Gopalan, Balasubramanian
, p. 4260 - 4264 (2008/09/21)
A variety of mono- and disubstituted phenols are alkylated with propargyl bromide to give phenyl 2-propynyl ethers, which were further coupled with aryl iodides under Sonogashira reaction conditions to give 3-phenoxy-1-aryl-1-propyne derivatives. The latt
Zn(OTf)2-catalyzed cyclization of proparyl alcohols with anilines, phenols, and amides for synthesis of indoles, benzofurans, and oxazoles through different annulation mechanisms
Kumar, Manyam Praveen,Liu, Rai-Shung
, p. 4951 - 4955 (2007/10/03)
Zn(OTf)2 (10 mol %) catalyzed the cyclization of propargyl alcohols with PhXH (X = O, NH) in hot toluene (100 °C) without additive and gave indole and benzofuran products with different structures. In such transformations, α-carbonyl intermedia
