Base-Promoted Tandem Reaction towards Conjugated Dienone or Chromone Derivatives with a Cyano Group: Insertion of Alkynes into C-C σ-Bonds of 3-Oxopropanenitriles
作者:Qiyi Yao、Lingkai Kong、Fangfang Zhang、Xianghua Tao、Yanzhong Li
DOI:10.1002/adsc.201700565
日期:2017.9.18
alkynes into the C–C σ-bonds of α-cyano ketones were established to construct highlyfunctionalizedconjugated olefins or chromone derivativesvia transition metal-free tandem reactions. These reactions are initialized through the nucleophilic attack of α-cyano ketones to alkynones followed by intramolecular nucleophilic addition/ring-opening to furnish the cyano-containing alkenes. In the cases of alkynones
A Mild, Highly Efficient Addition of Alkynes to Aldehydes Catalyzed by Titanium Dioxide‐Supported Silver Nanoparticles
作者:Min Yu、Yong Wang、Weijiang Sun、Xiaoquan Yao
DOI:10.1002/adsc.201100518
日期:2012.1
Titaniumdioxide‐supportedsilvernanoparticles were utilized as a highlyefficient catalyst for the addition of terminal alkynes to aldehydes to prepare propargylic alcohols with the promotion by triphenylphosphine. Both a significant support effect and a ligand effect were observed in the catalytic reaction. With this protocol, various propargylic alcohol derivatives were synthesized from aldehydes
A highly efficient palladium-catalyzed asymmetric synthesis of N-substituted 4-quinolones was developed via C−N coupling reaction. Various chiral quinolones were readily obtained with desirable enantioselectivity (up to 95% ee) and excellent yield (up to 99%), enabled by a simple system of palladium acetate and chiral ferrocene bisphosphine as auxiliary ligand. The corresponding racemic derivatives