Highly Efficient, Reversible Addition of Activated Methylene Compounds to Styrene Derivatives Catalyzed by Silver Catalysts
作者:Xiaoquan Yao、Chao-Jun Li
DOI:10.1021/jo050570n
日期:2005.7.1
A highlyefficient inter- and intramolecular addition of 1,3-diketone/β-ketoester to alkenes was developed by using silver catalysts. Silver triflate shows the highest catalytic activity. The reaction is reversible through the cleavage of a carbon−carbon bond by silver at an elevated temperature.
Directα-alkylation of carbonylcompounds represents a fundamental bond forming transformation in organic synthesis. We report the first ketone-alkylation using olefins and alcohols as simple alkylating agents catalyzed by graphene oxide. Extensive studies of the graphene surface suggest a pathway involving dual activation of both coupling partners. Notably, we show that polar functional groups have
Triflic acid adsorbed on silica gel as an efficient and recyclable catalyst for the addition of β-dicarbonyl compounds to alcohols and alkenes
作者:Pei Nian Liu、Fei Xia、Qing Wei Wang、Yu Jie Ren、Jun Qin Chen
DOI:10.1039/b926142g
日期:——
The silicagel supported triflic acid was readily prepared via simple absorption of TfOH onto chromatographic silicagel. This solid acid was applied as an efficient catalyst for the heterogeneous addition of various β-dicarbonyl compounds to a series of alcohols and alkenes, which afforded moderate to excellent yields under solvent-free conditions or in nitromethane. Moreover, this silicagel supported
Highly Efficient Addition of Activated Methylene Compounds to Alkenes Catalyzed by Gold and Silver
作者:Xiaoquan Yao、Chao-Jun Li
DOI:10.1021/ja0482637
日期:2004.6.1
A highlyefficient intermolecular addition of 1,3-diketones to alkenes catalyzed by AuCl3/AgOTf was developed. A mechanistic rationale for the reaction has been proposed via a alpha-C-H activation.
Efficient Copper(II)-Catalyzed Addition of Activated Methylene Compounds to Alkenes
作者:Yu Li、Zhengkun Yu、Sizhong Wu
DOI:10.1021/jo800836g
日期:2008.7.1
regioselective addition of β-diketones to styrenes, norbornene, cyclic enol ether, and diene has been realized by means of copper(II) triflate as the catalyst. The solvent effect is prominent on the reactions, and the desired addition products were obtained in good to excellent yields only in dioxane or ionic liquid [bmim]PF6. The mechanism suggests that copper(II) triflate activates the enolic O−H