An Access to Benzo[<i>a</i>]fluorenes, Benzo[<i>b</i>]fluorenes, and Indenes Triggered by Simple Lewis Acid
作者:Dakoju Ravi Kishore、Komal Goel、Chander Shekhar、Gedu Satyanarayana
DOI:10.1021/acs.joc.1c02724
日期:2022.3.4
cycloaromatization of 1,7-ynones toward synthesizing structurally diverse benzofluorene scaffolds. Remarkably, the present protocol promotes the formation of two consecutive C–C bonds intramolecularly and undergoes aromatization under mild reaction conditions to afford the tetracyclic benzo[a]fluorene frameworks. Besides, the formation of indenes was observed when 1-bromo-2-iodoarenes are relatively
An efficient intermolecular [Pd]-catalyzed C–C and intramolecular [Cu]-catalyzed C–O bonds formation: synthesis of functionalized flavans and benzoxepine
An efficient three-step strategy for the synthesis of functionalized flavans, starting from readily available 2-bromoiodobenzenes and aryl vinyl alcohols, is presented and successfully extended to benzoxepine. An intermolecular [Pd]-catalyzed C-C and an intramolecular [Cu]-catalyzed C-O bond formations have been employed as key transformations of the strategy. (C) 2012 Elsevier Ltd. All rights reserved.
Methanol as hydrogen source: Chemoselective transfer hydrogenation of α,β-unsaturated ketones with a rhodacycle
作者:Ahmed H. Aboo、Robina Begum、Liangliang Zhao、Zahoor H. Farooqi、Jianliang Xiao
DOI:10.1016/s1872-2067(19)63367-x
日期:2019.11
economic and easy-to-handle hydrogen source. It has rarely been used in transfer hydrogenation reactions, however. We herein report that a cyclometalated rhodium complex, rhodacycle, catalyzes highly chemoselectivehydrogenation of α,β-unsaturatedketones with methanol as the hydrogen source. A wide variety of chalcones, styryl methyl ketones and vinyl methyl ketones, including sterically demanding
A simple and practical method has been developed based on intermolecular [Pd]-catalyzed C–C and an intramolecular [Cu]-catalyzed C–O bond formations for the synthesis of flavans and benzoxepines. Interestingly, the method is amenable for the synthesis of a wide variety of flavans and benzoxepines with dense functionalities on aromatic moieties. Significantly, flavans and benzoxepines are present as