Reactivity of alumosiloxanes for the synthesis of new metal derivatives

Abstract

The subject of this work is the study of the reactivity of the polyalumosiloxane (tetrakis (µ2-hydroxo)-(µ2-tetraphenyldisilanoxy diolato)- aluminium) [(Ph2Si)2O3]4Al4(OH)4 (1) synthesized in 1997 by Veith et al.. The aim of the work is to modify this well-known compound by the introduction of alkaline-, main group- or transition-metals. The first part deals with the insertion of metal alkoxide or hydroxide into 1 and the substitution of hydrogen of the central Al4(OH)4-ring by the corresponding metals involving an enlargement of the central ring of 1. Still within the scope of the research, the synthesis of a new compound containing a cubic central arrangement of Li3O4Al was performed. Furthermore, the reactivity of 1 towards a sterically encumbered lithium compound has been studied. The second part includes the synthesis of new complex derivatives of 1 containing tin(II), nickel(II) and iron(III). The reaction between 1 and Diazasilastannetidine leads to a compound containing a tetra-nuclear Sn(II) entity. In addition, nickel(II) and iron(II) complexes have been obtained by the introduction of Bis-(acetylacetonato) nickel(II) and Tris-(acetylacetonato) iron(III) into 1 including ligands redistribution. The last part is devoted to the design of new aluminium hetero-metallasiloxane complexes containing Li, Ni, Co and Mg atoms resulting from the reaction of 1 with Bisacetylacetone dihydrate metal (II) or Grignard reagent.