ABSTRACT: The chemistry of 1,2,4,5-tetrazines has attracted considerable interest both from a synthetic and applicative standpoint. Recently, regioselective reactions with alkynes and alkenes have been reported to be favored once the tetrazine ring is coordinated to Re(I), Ru(II), and Ir(III) centers. Aiming to further explore the effects of metal coordination, herein, we unveil the unexplored reactivity of tetrazines with chalcogenocyanate anions. Thus, ruthenium(II) tetrazine complexes, [RuCl{κ2N-3-(2-pyridyl)-6-R-1,2,4,5-tetrazine}(η6-arene)]+ (arene = p-cymene, R = H, [1a]+, R = Me, [1b]+, R = 2-pyridyl, [1c]+; arene = C6Me6, R = H, [1d]+, R = Me, [<
