Two-Step Synthesis of Unsymmetrical Diaryl Sulfides by Electrophilic Thiolation of Non-functionalized (Hetero)arenes.

This article reports the efficient preparation of a series of unsymmetrically substituted thioethers through a two-step procedure consisting of an initial metal-free C-H sulfenylation of electron-rich (hetero)arenes with newly prepared succinylthioimidazolium salts. Subsequent reaction of the arylthioimidazolium intermediates with Grignard reagents afford the desired thioethers. The synthetic protocol described is modular, scalable, and high yielding, and provides access to sulfides that are not easy to obtain through the existing methodologies. Importantly, no prefunctionalization of the initial (hetero)arene is required.