Room temperature and phosphine free palladium catalyzed direct C-2 arylation of indoles

We report the first room-temperature direct C-2 arylation of indoles with iodoarenes by using a highly electrophilic palladium catalyst generated in situ from Pd(OAc)(2) and a silver carboxylate. These mild conditions permit a broad set of functionalities both in the indole and in the aryl iodide units such as free alcohols, phenols, aldehydes, bromides, or nitriles, thus allowing the synthesis of a variety of novel compounds in excellent yields.