The reduction of elemental selenium by samarium diiodide led to selective formation of selenolate anion species (Se~(2-)_2 and Se~(2-)), these nucleophilic species reacted readly with sodium alkyl thiosulfates to afford dithiodiselenides and dithioselenides in moderate to good yield under mild conditions. The reduction of elemental selenium by samarium diiodide led to selective formation of selenolate anion species (Se ~ (2 -) _2 and Se ~ (2-)), these nucleophilic species reacted with sodium alkyl thiosulfates to afford dithiodiselenides and dithioselenides in moderate to good yield under mild conditions.