Mechanistic Insights on Iodine(III) Promoted Metal-Free Dual C-H Activation Involved in the Formation of a Spirocyclic Bis-oxindole

作者：Sreenithya A; Sunoj Raghavan B^*

来源：Organic Letters, 2014, 16(23): 6224-6227.

DOI：10.1021/ol503161g

The mechanism of a metal-free, phenyliodine(III) bis(trifluoroacetate) promoted, dual aryl C-H activation of an anilide to a spirocyclic bis-oxindole is examined using density functional theory (M06-2X). The most preferred pathway proceeds through the involvement of a novel iodonium ion intermediate and a pivotal trifluoroacetate counterion. The two sequential aryl C-H activations, assisted by trifluoroacetate as well as the superior leaving group ability of PhI, facilitate the formation of spirocyclic bis-oxindole.