## Trimetallaborides as starting points for the syntheses of large metal-rich molecular borides and clusters

Please always quote using this URN: urn:nbn:de:bvb:20-opus-191511
• Treatment of an anionic dimanganaborylene complex ([{Cp(CO)$$_2$$Mn}$$_2$$B]$$^-$$) with coinage metal cations stabilized by a very weakly coordinating Lewis base (SMe$$_2$$) led to the coordination of the incoming metal and subsequent displacement of dimethylsulfide in the formation of hexametalladiborides featuring planar four-membered M$$_2$$B$$_2$$ cores (M = Cu, Au) comparable to transition metal clusters constructed around four-membered rings composed solely of coinage metals. The analogies between compounds consisting of B$$_2$$M$$_2$$Treatment of an anionic dimanganaborylene complex ([{Cp(CO)$$_2$$Mn}$$_2$$B]$$^-$$) with coinage metal cations stabilized by a very weakly coordinating Lewis base (SMe$$_2$$) led to the coordination of the incoming metal and subsequent displacement of dimethylsulfide in the formation of hexametalladiborides featuring planar four-membered M$$_2$$B$$_2$$ cores (M = Cu, Au) comparable to transition metal clusters constructed around four-membered rings composed solely of coinage metals. The analogies between compounds consisting of B$$_2$$M$$_2$$ units and M$$_4$$ (M = Cu, Au) units speak to the often overlooked metalloid nature of boron. Treatment of one of these compounds (M = Cu) with a Lewis-basic metal fragment (Pt(PCy$$_3$$)$$_2$$) led to the formation of a tetrametallaboride featuring two manganese, one copper and one platinum atom, all bound to boron in a geometry not yet seen for this kind of compound. Computational examination suggests that this geometry is the result of d$$^{10}$$-d$$^{10}$$ dispersion interactions between the copper and platinum fragments.