A Stable Naked Dithiolene Radical Anion and Synergic THF Ring-Opening

Reaction of the lithium dithiolene radical 2• with the imidazolium salt [{(Me)­CN­(i-Pr)}2CH]+[Cl]− (in a 1:1 molar ratio) gives the first stable naked anionic dithiolene radical 3•, which, when coupled with hexasulfide, [{(Me)­CN­(i-Pr)}2CH]+2[S6]2– (4), and N-heterocyclic silylene 5, unexpectedly results in synergic THF ring-opening via a radical mechanism.