在这里,我们报道了由对甲苯磺酸促进苯并稠合的O杂环的首次发散合成,该反应促进了级联反应,涉及炔烃水合,双环化,环收缩和炔醇裂解C-O键。通过获得熔融的苯并[ b ]氧杂环庚烷中间体的X射线结构来验证反应机理。而且,一些获得的衍生物可以转化为2,3-二取代的萘醌,作为天然产物和生物活性分子中的重要结构基序。
Nickel-Catalyzed Intramolecular Nucleophilic Addition of Aryl Halides to Aryl Ketones for the Synthesis of Benzofuran Derivatives
作者:Chen-Liang Deng、Xiao-Rui Zhu
DOI:10.1055/s-0040-1706662
日期:2021.5
A nickel-catalyzed intramolecularnucleophilicaddition reaction of aryl halides to arylketones 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.
ZnBr<sub>2</sub>-Mediated Cascade Reaction of <i>o</i>-Alkoxy Alkynols: Synthesis of Indeno[1,2-<i>c</i>]chromenes
作者:Amol Milind Garkhedkar、Gopal Chandru Senadi、Jeh-Jeng Wang
DOI:10.1021/acs.orglett.6b03642
日期:2017.2.3
A Lewis acid-mediatedcascade annulation of o-alkoxy alkynols in the presence of ZnBr2 has been developed. The cascadecyclization proceeds through a 5-exo-dig cyclization followed by a Friedel–Crafts reaction and ring-opening sequence to synthesize indeno[1,2-c]chromenes. This protocol provides a broad substrate scope in moderate to good yields with high regioselectivity. The reaction with benzo-fused
已经开发了在ZnBr 2存在下路易斯酸介导的邻烷氧基炔醇的级联环化反应。级联环化是通过5- exo- dig环化进行的,然后进行Friedel-Crafts反应和开环序列以合成茚并[1,2- c ]色烯。该方案以中等至良好的产率和高的区域选择性提供了广泛的底物范围。与苯并稠合的环烷基酮的反应产生了意外的炔烃C–C键断裂,从而导致了稠合的多环。
Iron-catalyzed annulations of 2-(2-alkynyl)phenoxy)-1-arylethanones leading to substituted naphthalen-1-ols
作者:Zhi-Qiang Wang、Yun Liang、Yong Lei、Ming-Bo Zhou、Jin-Heng Li
DOI:10.1039/b911669a
日期:——
A novel intramolecular annulation of 1-(2-alkynylphenoxy)propan-2-ones catalyzed by iron, an economical and environmentally-benign transition metal, has been developed; this new atom-economical route includes dual C–H functionalizations to construct the naphthalen-1-ol or anthracen-1-ol skeletons.
Palladium-catalyzed annulations of arynes with 2-(2-iodophenoxy)-1-substituted ethanones
作者:Rong-Jiang Li、Shao-Feng Pi、Yun Liang、Zhi-Qiang Wang、Ren-Jie Song、Guo-Xiang Chen、Jin-Heng Li
DOI:10.1039/c0cc02720k
日期:——
Palladium-catalyzedannulations of arynes with 2-(2-iodophenoxy)-1-substituted ethanones for the synthesis of 6H-benzo[c]chromenes are presented. This mild route allows formation of two new carbon-carbon bonds via an alpha-arylation/annulation process.
tert-BuOK-mediated carbanion–yne intramolecular cyclization: synthesis of 2-substituted 3-benzylbenzofurans
作者:Po-Yuan Chen、Tzu-Pin Wang、Keng-Shiang Huang、Chai-Lin Kao、Jui-Chi Tsai、Eng-Chi Wang
DOI:10.1016/j.tet.2011.09.144
日期:2011.12
A mild, efficient, and regioselective carbanion-yne intramolecular cyclization mediated by t-BuOK for the synthesis of 2-substituted 3-benzylbenzofurans is developed. It was started from o-iodophenol (1), based on O-alkylation, and the Sonogashira reaction in sequence to produce 2-(2-phenylethynyl-phenoxy)-1-arylalkanones (5). An intramolecular carbanion-yne 5-exo-dig cyclization reaction of 5, which was mediated by t-BuOK, yielded title benzofurans in good yields. (C) 2011 Elsevier Ltd. All rights reserved.