The Cinchona Primary Amine-Catalyzed Asymmetric Epoxidation and Hydroperoxidation of α,β-Unsaturated Carbonyl Compounds with Hydrogen Peroxide
作者:Olga Lifchits、Manuel Mahlau、Corinna M. Reisinger、Anna Lee、Christophe Farès、Iakov Polyak、Gopinadhanpillai Gopakumar、Walter Thiel、Benjamin List
DOI:10.1021/ja402058v
日期:2013.5.1
Using cinchona alkaloid-derived primary amines as catalysts and aqueous hydrogenperoxide as the oxidant, we have developed highly enantioselective Weitz-Scheffer-type epoxidation and hydroperoxidation reactions of α,β-unsaturated carbonylcompounds (up to 99.5:0.5 er). In this article, we present our full studies on this family of reactions, employing acyclic enones, 5-15-membered cyclic enones, and
Stereochemistry of the Tetrabutylammonium Cyanide-Catalyzed Cyanosylilation of Cyclic α,β-Epoxyketones – Dependence of the Diastereoselectivity on the Ring Size
Isocyano Enones: Addition–Cyclization Cascade to Oxazoles
作者:Allen Chao、J. Armando Lujan-Montelongo、Fraser F. Fleming
DOI:10.1021/acs.orglett.6b01147
日期:2016.7.1
Copper iodide catalyzes the conjugate addition of organometallic and heteroatom nucleophiles to isocyano enones to afford oxazoles. A range of enolates, metalated nitriles, amines, and thiols undergo catalyzed conjugate addition to cyclic and acyclic oxoalkene isocyanides. Mechanistic studies suggest that copper complexation facilitates the nucleophilic attack on the isocyano enone to generate an enolate
Multipathways for the Synthesis of Fused Bicyclic 2-Aminothiazolyl Compounds Tuned by Ring Size
作者:Xiaoyong Xu、Pengfei Liu、Hongfeng Shen、Xusheng Shao、Zhong Li
DOI:10.1055/s-0034-1379100
日期:——
methodology for the synthesis of fused bicyclic 2-aminothiazolyl compounds has been developed, using cyclocondensation of aromatic thioureas with α,β-epoxy cycloketones in alcohol under microwave irradiation without any catalyst. The product distribution is related to the ring size of α,β-epoxy cycloketones. Mechanistic studies suggest that the reactions share analogous bicyclic dihydroxy intermediates but