Homoleptic triisopropylsilylarsandiides of magnesium and divalent tin

The magnesiation of H2AsSi'Pr-3 yields the tetramer [(THF)MgAsSi'Pr-3](4) (1) with a central Mg4As4 heterocubane moiety. The reaction of Sn[N(SiMe3)(2)](2) with triisopropylsilylarsane gives the hexamer [(SnAsSiPr3)-Pr-i](6) (2) with an inner hexagonal Sn,As, prism. The molecular structures of both these compounds have been determined. (C) 2000 Elsevier Science B.V. All rights reserved.