Investigation of Sn(IV) and Sn(II) by dianionicligand compounds Supported by Nitrogen-Based Ligands

Abstract

Synthetic routes to a series of tin compounds incorporating nitrogen-based
chelating ligands are described. The β-diketiminato tin chloride precursor was
utilized to isolate the first tin-phosphorus tin compound using this ligand,
[(HC{C(Me)NAr}2)SnPPh2]. A diamide ligand was employed to investigate tin (II)
and (IV) compounds. Two tin (II) and (IV) compounds, [(Me2Si{ArN}2)SnPh2] and
[Li(OEt)2](Me2Si{ArN}2)SnPh2], were formed via reaction of the lithiated
preligand, [Me2Si{ArNLi}2]+Sn(IV). Finally a novel Sn(II) N-heterocyclic
stannylene compound was formed by reaction of the preligand with SnCl4.
The diamide ligand was found to be suitable for both Sn(IV) and Sn(II)
compounds. Reaction to obtain the tin dichloride compound resulted in the
formation of [Li(OEt2)2][LSnCl3], which was characterised to be the chloro-bridged
lithium chloride adduct of the desired compound. To gain more information on this
reaction it was repeated with SnCl2Ph2 to attain the tin diphenyl analogue, which
was established with no problems. Reaction to generate a N-heterocylic stannylene
was extremely interesting, as this compound has great potential for further reactivity
both independently and with regards to the aim of this product, which was to
generate a tin-phosphorus multiple bond.