Metal-Free Synthesis of Thiosulfonates via Insertion of Sulfur Dioxide

A simple and catalyst-free strategy was developed for the synthesis of unsymmetrical thiosulfonates using readily available DABCO center dot(SO2)(2) as a solid and bench-stable sulfur dioxide surrogate. The corresponding thiosulfonates were obtained through a radical pathway with good functional group tolerance. This strategy offers a promising synthesis method for the construction of diverse and useful thiosulfonates in the field of synthetic and pharmaceutical chemistry and extends the number of still limited sulfur dioxide fixation strategies.