Hydrogen-Bonded Matched Ion Pair Gold(I) Catalysis
作者:Àlex Martí、Gala Ogalla、Antonio M. Echavarren
DOI:10.1021/acscatal.3c02638
日期:2023.8.4
The enantioselective reaction of 1,6-enynes with O-, N-, and C-nucleophiles has been developed by matched ion pair gold(I) catalysis in which the chiral gold(I) cation and anion are H-bonded through a urea group. Very high levels of enantiocontrol are achieved (up to >99:1 er) for a broad scope of substrates. DFT studies demonstrate the importance of the H-bond donor group in anchoring the matched
Towards asymmetric Au-catalyzed hydroxy- and alkoxycyclization of 1,6-enynes
作者:Chung-Meng Chao、Emilie Genin、Patrick Y. Toullec、Jean-Pierre Genêt、Véronique Michelet
DOI:10.1016/j.jorganchem.2008.08.008
日期:2009.2
The efficiency of a Au(III)/chiral ligand system has been studied. The association of several chiral mono- and bidentate phosphanes with gold has been tested in the formal addition of an oxygen nucleophile to an alkene followed by a cyclization process, namely the hydroxycyclization reaction of 1,6-enynes. The use of ( R)-4-MeO-3,5-(t-Bu)(2)-MeOBIPHEP ligand led to clean cycloisomerizations and afforded the highest enantiomeric excesses. The enantiomeric excesses were highly dependant on the substrate/nucleophile combination. A P-31 NMR study of the catalytic species tends to prove that Au( III) catalyst may be reduced to Au( I) intermediate in the presence of phosphanes. (C) 2008 Elsevier B.V. All rights reserved.
Gold-Catalyzed Hydroxy- and Alkoxycyclization of Functionalized Enynes
A general Au III catalytic system is described for the efficient hydroxy- and alkoxycyclization reactions of 1,6-enynes. The reactions lead to carbo- and heterocyclic alcohols or ethers in good to excellent yields. The cyclizations are conducted in the presence of AuCl 3 /AgSbF 6 /PPh 3 catalyst in dioxane-water or various alcohols at room temperature. The hydroxycyclization reactions of 1,7-enynes
描述了一种通用的 Au III 催化系统,用于 1,6-烯炔的有效羟基和烷氧基环化反应。该反应导致碳和杂环醇或醚的产率良好至极好。在AuCl 3 /AgSbF 6 /PPh 3 催化剂的存在下,在二恶烷-水或各种醇中在室温下进行环化。1,7-烯炔的羟基环化反应得到甲基酮或甲基酮和碳环醇的混合物。