What is "fluorosulfonate"

Fluorosulfonate, in organic chemistry, is a functional group that has the chemical formula F-SO-O-R, and typically is a very good leaving group. In inorganic chemistry, fluorosulfonate is the anion F-SO-O, the conjugated base of fluorosulfonic acid.

Organic ( alkyl) fluorosulfonates are usually strong alkylation agents, similar to triflate esters (FC-SO-OR). But unlike the triflate group, the fluorosulfonate group is not stable against hydrolysis. Therefore, fluorosulfonate esters are less frequently used as alkylation agents than triflate esters.