Formation of [(CnC1imTe)4Hg]2+ (n = 6, 8) upon in‐situ Generation of Dialkylimidazole‐2‐Tellurones in Ionic Liquids at Room Temperature. Issue 40 (16th October 2018) - Donsbach, Carsten
Abstract : The synthesis of a homoleptic Hg II complexes with in situ‐formed N‐heterocyclic carbene telluride ligands is reported. Tetrakis(1‐hexyl‐3‐methylimidazole‐2‐tellurone) mercury(II), [(C6 C1 imTe)4 Hg] 2+ (1 ), and tetrakis(1‐octyl‐3‐methylimidazole‐2‐tellurone) mercury(II), [(C8 C1 imTe)4 Hg] 2+ (2 ), emerge from reaction mixtures containing telluridomercurate anions and potassium cations in imidazolium‐based ionic liquids (Cn C1 Im)[BF4 ] ( n = 6, 8), if these are exposed to ambient conditions, that is, air, moisture and room temperature. The compounds crystallize with two of the ionic liquid cations each, and form van der Waals dimers via Te··· Te interactions in the crystal. Although being coordinated in a homoleptic manner, the orientation of the imidazolium ligands is such that two of them undergo π‐stacking interactions, while the others interact with neighboring units via their alkyl chains. Abstract : The [BF4 ] – salts of the very unusual complex cations tetrakis(1‐alkyl‐3‐methylimidazole‐2‐tellurone) mercury(II), [(Cn C1 imTe)4 Hg] 2+ (1, n = 6 and2, n = 8), were observed upon in situ formation of the corresponding tellurones in a side reaction of ionothermal chalcogenido metalate syntheses. These reactions point towards carbene formation from imidazolium based ionic liquids. The cations form dimers that undergo Te··· Te and π‐stacking interactions.