Ruthenium‐Catalyzed Synthesis of Aryl and Alkenyl Halides from Fluorosulfonates

Aryl and alkenyl halides are widely used as key intermediates in organic synthesis, particularly for the formation of organometallic reagents or as radical precursors. They are also found in pharmaceutical and agrochemical ingredients. In this work, the synthesis of aryl and alkenyl halides from the corresponding fluorosulfonates using commercially available ruthenium catalysts is reported. Notably, this is the first conversion of phenols to aryl halides that is efficient with chloride, bromide, and iodide. Fluorosulfonates are readily prepared using sulfuryl fluoride (SO2F2) and less expensive substitutes for triflates. Although aryl fluorosulfonates and their reactions are well known, this is the first report of an efficient coupling of alkenyl fluorosulfonates. To finish, it was demonstrated, by means of representative examples, that the reaction is possible in a one‐pot process, starting directly from phenol or aldehyde. The relevance of aryl fluorosulfonates in coupling reactions has increased over the past decade. Surprisingly, the use and synthesis of alkenyl fluorosulfonates is still poorly described. In this paper, the advantageous use of aryl and alkenyl fluorosulfonates instead of the corresponding triflates is reported to synthesize aryl and alkenyl halides using halide salts and commercially available ruthenium catalysts.