Convenient and Efficient Synthesis of Functionalized 2-Sulfenylindoles.

A simple, efficient, and practical sulfenylation at the C2 position of -tosylindoles under mild conditions was developed. The designed transformation is based on the reaction of -tosylindoles with BuLi and -alkyl, and -aryl phosphorodithioates or thiotosylates to produce 2-sulfenylindoles in moderate to high yields. The presence of additional hydroxy, carboxy, or amino functionalities did not disturb the formation of products.