Cu‐Promoted Sydnone Cycloadditions of Alkynes: Scope and Mechanism Studies
作者:Júlia Comas‐Barceló、Robert S. Foster、Béla Fiser、Enrique Gomez‐Bengoa、Joseph P. A. Harrity
DOI:10.1002/chem.201406118
日期:2015.2.16
reaction of sydnones and terminal alkynes, providing significant reduction in reaction times. Specifically, the use of Cu(OTf)2 is found to provide 1,3‐disubstituted pyrazoles, whereas simply switching the promoter system to Cu(OAc)2 allows the corresponding 1,4‐isomers to be produced. The mechanism of the Cu‐effect in each case has been investigated by experimental and theoretical studies, and they