N-Heterocyclic Carbene Coinage Metal Complexes of the Germanium-Rich Metalloid Clusters [Ge?R?]^- and [Ge?R^I?]²^- with R = Si(ⁱPr)? and R^I = Si(TMS)?.

ABSTRACT: We report on the synthesis of novel coinage metal NHC (N-heterocyclic carbene) compounds of the germanium-rich metalloid clusters [Ge?R?]^- and [Ge?R^I?]²^- with R = Si(ⁱPr)? and R^I = Si(TMS)?. NHC^DippCu{?³Ge?R?} with R = Si(ⁱPr)? (1) represents a less bulky silyl group-substituted derivative of the known analogous compounds with R = Si(ⁱBu)? or Si(TMS)?. The coordination of the [NHC^DippCu]? moiety to the cluster unit occurs via one triangular face of the tri-capped trigonal prismatic [Ge?] cluster. Furthermore, a series of novel Zintl cluster coinage metal NHC compounds of the type (NHCM)?{?³Ge?R^I?} (R^I = Si(TMS)? M = Cu, Ag and Au; NHC = NHC^Dipp or NHC^Mes) is presented. These novel compounds represent a new class of neutral dinuclear Zintl cluster coinage metal NHC compounds, which are obtained either by the stepwise reaction of a suspension of K₁₂Ge₁₇ with Si(TMS)?Cl and the coinage metal carbene complexes NHCMCl (M = Cu, Ag, Au), or via a homogenous reaction using the preformed bis-silylated cluster K?[Ge?(Si(TMS)?)?] and the corresponding NHCMCl (M = Cu, Ag, Au) complex. The molecular structures of NHC^DippCu{?³Ge?(Si(ⁱPr)?)?} (1) and (NHC^DippCu)?{?³-Ge?(Si(TMS)?)?} (2) were determined by single crystal X-ray diffraction methods. In 2, the coordination of the [NHC^DippCu]? moieties to the cluster unit takes place via both open triangular faces of the [Ge?] entity. Furthermore, all compounds were characterized by means of NMR spectroscopy (¹H, ¹³C, ²⁹Si) and ESI-MS.

SUBMITTER: Geitner FS 

PROVIDER: S-EPMC6152075 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature