(N,Se) and (Se,N,Se) Ligands Based on Carborane and Pyridine Fragments – Reactivity of 2,6-[(1′-Me-1′,2′-closo-C2B10H10)SeCH2]2C5H3N towards Copper and Silver.

Two new closo-carborane selenolated ligands, 2-[(1′-Me-1′,2′-closo-C2B10H10)SeCH2]C5H4N (L1) and 2,6-[(1′-Me-1′,2′-closo-C2B10H10)SeCH2]2C5H3N (L2), were prepared by the C–H activation of 1-Me-1,2-C2B10H11 with nBuLi, followed by the insertion of elemental selenium into the C–Li bond and reaction with 2-(BrCH2)C5H4N or 2,6-(BrCH2)2C5H3N, respectively. The closo species L1 and L2 were deboronated with CsF to give the nido-carborane cesium salts Cs[2-{(1′-Me-1′,2′-nido-C2B9H9)SeCH2}C5H4N] (1) and Cs2[2,6-{(1′-Me-1′,2′-nido-C2B9H9)SeCH2}2C5H3N] (2). The isolation of the complexes [Ag(OTf)(L2)] (3, OTf = triflate), [Ag(PPh3)(L2)][OTf] (4), [Cu(L2)(MeCN)][PF6] (5), and [Cu(L2)2][PF6] (6) indicates the coordination ability of L2 towards these metals. The molecular structures of L1 and L2 were established by single-crystal X-ray diffraction. Quantum-chemical calculations confirmed the molecular geometries and also the presence of C–H···Se intramolecular interactions as well as C–H···H–B and B–H···π intermolecular interactions. [ABSTRACT FROM AUTHOR]