Ruthenium-Catalyzed Oxidative Amidation of Alkynes to Amides
作者:Andrea Álvarez-Pérez、Miguel A. Esteruelas、Susana Izquierdo、Jesús A. Varela、Carlos Saá
DOI:10.1021/acs.orglett.9b01993
日期:2019.7.5
Complex CpRuCl(PPh3)2 catalyzes reactions of terminal alkynes with 4-picoline N-oxide and primary and secondary amines to afford the corresponding amides. The reactions occur in chlorinated solvent and aqueous medium, showing applications in peptide chemistry. Stoichiometric studies reveal that the true catalysts of the processes are the vinylidene cations [CpRu(═C═CHR)(PPh3)2]+ which are oxidized
Amide bond synthesis via silver(I) N-heterocyclic carbene-catalyzed and tert-butyl hydroperoxide-mediated oxidative coupling of alcohols with amines under base free conditions
free method for amide bond construction via oxidative coupling of alcohols with amines catalyzed by Silver(I) N-heterocyclic carbenes (Ag(I)-NHCs) and mediated by tert-butyl hydroperoxide (TBHP) in ethanol. The results of controlled experiments suggest that the oxidative coupling proceeds through the formation of aldehyde, then subsequent attack by amine to give hemiaminal, which can then be oxidized