Cu(I)-Catalyzed Domino Reactions: Efficient and Selective Synthesis of 4<i>H</i>-Chromenes and Naphthalenes
作者:Chandi C. Malakar、Dietmar Schmidt、Jürgen Conrad、Uwe Beifuss
DOI:10.1021/ol200347g
日期:2011.4.15
Depending on the ratio of the substrates and the reaction conditions, the Cu(I)-catalyzed domino reaction between bromobenzyl bromides and beta-ketoesters exclusively yields either 4H-chromenes or naphthalenes.
Copper(I)-Catalyzed Intramolecular O-Arylation for the Synthesis of 2,3,4,9-Tetrahydro-1<i>H</i>-xanthen-1-ones with Low Loads of CuCl
作者:Kavitha Sudheendran、Chandi C. Malakar、Jürgen Conrad、Uwe Beifuss
DOI:10.1021/jo3018318
日期:2012.11.16
As little as 0.5 mol % CuCl is sufficient to catalyze the intramolecular O-arylation of easily accessible 2-(2-bromobenzyl)cyclohexane-1,3-diones to provide the corresponding 2,3,4,9-tetrahydro-1H-xanthen-1-ones with yields ranging from 83% to 99%.
Pd-catalysed intramolecular regioselective arylation of 2-pyrones, pyridones, coumarins and quinolones by C–H bond functionalization
作者:Marie-Therese Nolan、Joshua T.W. Bray、Kevin Eccles、Man Sing Cheung、Zhenyang Lin、Simon E. Lawrence、Adrian C. Whitwood、Ian J.S. Fairlamb、Gerard P. McGlacken
DOI:10.1016/j.tet.2014.04.029
日期:2014.10
The intramolecular arylation of 2-pyrones, 2-pyridones, coumarins and quinolones is reported using Pd-II precatalyst sources without added phosphine ligands. The excellent yields and convenient reagents enables the formation of various analogues containing these moieties, and access to potential biologically active candidates. Stoichiometric studies were carried out to provide an insight into the oxidation addition step. A switch in regioselectivity, together with a hydrodebromination process, was observed in the case of a 3-bromo-2-pyrone. (C) 2014 Elsevier Ltd. All rights reserved.