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
络合物CpRuCl(PPh 3)2催化末端炔烃与4-甲基吡啶N-氧化物以及伯胺和仲胺的反应,得到相应的酰胺。反应发生在氯化溶剂和水性介质中,显示出在肽化学中的应用。化学计量的研究表明,该工艺的真正的催化剂是亚乙烯基的阳离子[CPRU(═C═CHR)(PPH 3)2 ] +,其被氧化成的Ru(η 2由-CO)-ketenes Ñ氧化物。最后,伯胺和仲胺向游离酮的亲核加成产生相应的酰胺。