Copper-Catalysed Direct C–H Bond Oxidative Acetoxylation and Iodination of Indoles

A novel Cu(OAc)2-catalysed direct C–H bond oxidative acetoxylation and iodination of indoles using PhI(OAc)2 as a terminal oxidant is reported. Adopting this method, a series of 3-iodoindoles and indol-3-yl acetates were obtained in nearly 1:1 ratio yield.

Facile preparation of indoles and 1,2-benzothiazine 1,1-dioxides: nucleophilic addition of sulfonamides to bromoacetylenes and subsequent palladium-catalyzed cyclization

Bromine as a double agent: The bromine atom in 1-bromo-1-alkynes works as an electron-withdrawing group to effect the nucleophilic addition of sulfonamides. It again plays a pivotal role in the palladium-catalyzed cyclization of the resultant (Z)-2-(sulfonylamino)-1-bromoalkenes into nitrogen heterocycles (see scheme).

Exploring the oxidative cyclization of substituted N-aryl enamines: Pd-catalyzed formation of indoles from anilines

The direct Pd-catalyzed oxidative coupling of two C-H-bonds within N-aryl-enamines 1 allows the efficient formation of differently substituted indoles 2. In this cross-dehydrogenative coupling, many different functional groups are tolerated and the starting material N-aryl-enamines 1 can be easily prepared in one step from commercially available anilines. In addition, the whole sequence can also be run in a one-pot fashion. Optimization data, mechanistic insight, substrate scope, and applications are reported in this full paper.