Dendrimeric silatrane wedges

Abstract

The first three generations of a silatrane-containingdendrimeric wedge have been synthesised and isolated. This organosilicon dendrimeric wedge is the first example containing pentacoordinate silicon. The branching multiplicity, M, has been directed in the synthesis method, to form molecule 1 where M = 2 at each silatrane branching point. A second route was used where M = 3, 2 and 1 at successive branching points to form a second generation wedge 2. Electrospray mass spectrometry has been successfully used in the characterisation of the various silatranes. At low cone voltages, the compounds containing a residual trialkanolamine group predominantly show strong multiply charged ions of the type [M + H + xNH₄]^{(x+1 )+} (x = 0–3), while those compounds containing epoxy groups, show strong [M + xNH₄]^x+ ions, where x = 1–4. At high cone voltages the silatranyl cation fragment can be detected.