Access to Spirocyclized Oxindoles and Indolenines via Palladium-Catalyzed Cascade Reactions of Propargyl Carbonates with 2-Oxotryptamines and Tryptamines
作者:Antoinette E. Nibbs、Thomas D. Montgomery、Ye Zhu、Viresh H. Rawal
DOI:10.1021/acs.joc.5b00277
日期:2015.5.15
through a process wherein the first nucleophilic unit on the oxindole or indole reacts with an allenyl-palladium species, formed from oxidative addition of Pd(0) to propargyl carbonates, to generate a π-allyl palladium intermediate that then reacts further with the second nucleophilic component of the oxindole or indole. The cascade process forges two bonds en route to spirocyclized oxindole and indolenine
A study on the SN2-type ringopeningreactions of aziridines with indoles as nucleophiles is reported. Under gold(I) catalysis a great variety of tryptamine derivatives were prepared in good to excellent yields with complete stereocontrol when chiral aziridines were used. We demonstrated that cationic gold(I) catalysts are superior Lewis acids to the previously reported group 3, 12 and 13 metals in