1D and 3D Polymeric Manganese(II) Thiolato Complexes: Synthesis, Structure, and Properties of ∞3[Mn4(SPh)8] and ∞1[Mn(SMes)2].
Andreas EichhöferSergei LebedkinPublished in: Inorganic chemistry (2017)
Reactions of [Mn{N(SiMe3)2}2]2 with 2.1 equiv of RSH, R = Ph or Mes = C6H2-2,4,6-(CH3)3, yield compounds of the formal composition "Mn(SR)2". Single-crystal X-ray diffraction reveals that ∞1[Mn(SMes)2] forms one-dimensional chains in the crystal via μ2-SMes bridges, whereas ∞3[Mn4(SPh)8] comprises a three-dimensional network in which adamantanoid cages composed of four Mn atoms and six μ2-bridging SPh ligands are connected in three dimensions by doubly bridging SPh ligands. Thermogravimetric analysis and powder diffractometry indicate an reversible uptake of solvent molecules (tetrahydrofuran) into the channels of ∞1[Mn(SMes)2]. Magnetic measurements reveal antiferromagnetic coupling for both compounds with J = -8.2 cm-1 (∞1[Mn(SMes)2]) and -10.0 cm-1 (∞3[Mn4(SPh)8]), respectively. Their optical absorption and photoluminescence (PL) excitation spectra display characteristic d-d bands of Mn2+ ions in the visible spectral region. Both compounds emit bright phosphorescence at ∼800 nm at low temperatures (<100 K). However, only ∞1[Mn(SMes)2] retains a moderately intense emission at ambient temperature (with a quantum yield of 1.2%). Similar PL properties are also found for the related selenolate complexes ∞1[Mn(SeR)2] (R = Ph, Mes).