Facile Construction of the Benzofuran and Chromene Ring Systems via Pd<sup>II</sup>-Catalyzed Oxidative Cyclization
作者:So Won Youn、Jeong Im Eom
DOI:10.1021/ol051264z
日期:2005.7.1
text]. We herein report the development of one-pot procedures for the conversion of allyl aryl ethers to 2-methylbenzofurans (via sequential Claisenrearrangement and oxidative cyclization) and for the conversion of aryl homoallyl ethers to chromenes (via direct oxidative cyclization). It is likely that both reactions proceed via a common Pd-catalyzed pathway involving olefin activation, nucleophilic
Synthesis of Benzofuran and Indole Derivatives Catalyzed by Palladium on Carbon
作者:Anatoli Savvidou、Dimitrios IoannisTzaras、Giorgos S. Koutoulogenis、Alexis Theodorou、Christoforos G. Kokotos
DOI:10.1002/ejoc.201900577
日期:2019.6.30
A cheap, easy‐to‐execute and sustainable synthetic methodology for the synthesis of indoles and benzofurans was developed utilizing Pd/C as the promoter. A great variety of substituted ortho‐allyl anilines or phenols were utilized, leading to products in moderate yields. Recycling of the catalyst up to five times has been achieved.
Brønsted Acid Catalyzed Functionalization of Aromatic Alcohols through Nucleophilic Substitution of Hydroxyl Group
作者:Abhishek Kumar Mishra、Srijit Biswas
DOI:10.1021/acs.joc.5b02849
日期:2016.3.18
have been substituted by O-, S-, N-, and C-centered nucleophiles under solvent-free reaction conditions. The products are generated in good to excellent yields. para-Toluenesulfonic acid exhibits the best catalytic activity compared to other Brønstedacids. Experimental observations suggest that the reaction proceeds through the intermediacy of the keto tautomer of naphthol. Nucleophilic addition to
在无溶剂反应条件下,萘酚和互变异构酚衍生物的羟基已被O-,S-,N-和C中心的亲核试剂取代。产生的产品良率极佳。与其他布朗斯台德酸相比,对甲苯磺酸显示出最佳的催化活性。实验观察表明该反应通过萘酚的酮互变异构体的中间体进行。亲核加成到羰基上,然后除去水,得到所需产物。本方法提供了对取代的萘[2,1- b ]呋喃衍生物的访问。使用N生成的产品以中心为中心的亲核试剂可以进一步转化为重要种类的有机分子,例如苯并咔唑和咪唑衍生物。
One-Step Regioselective Synthesis of Benzofurans from Phenols and α-Haloketones
Reported here is the direct synthesis of naphthofurans and benzofurans from readily available phenols and α-haloketones promoted by titanium tetrachloride which combines Friedel–Crafts-like alkylation and intramolecular cyclodehydration into one step. This simple protocol allows for the formation of a variety of high value naphthofurans and benzofurans within which a series of cyclic and acyclic groups