885677-22-5Relevant academic research and scientific papers
Lanthanum and alkali metal coordination chemistry of the bis(dimethylphenylsilyl)amide ligand
Evans, William J.,Rego, Daniel B.,Ziller, Joseph W.
, p. 3437 - 3443 (2006)
The coordination chemistry of the bis(dimethylphenylsilyl)amide ligand, [N(SiMe2Ph)2]1-, with sodium, potassium, and lanthanum has been investigated for comparison with the more commonly used [N(SiMe3)2]1- and [N(SiHMe2) 2]1- ligands. HN(SiMe2Ph)2 reacts with KH to produce KN(SiMe2Ph)2, 1, which crystallizes from toluene as the dimer [KN(SiMe2Ph)2(C 7H8)]2, 2. The structure of 2 shows that the [N(SiMe2Ph)2]1- ligand can function as a polyhapto ligand with coordination from each phenyl group as well as the normal nitrogen ligation and agostic methyl interactions common in methylsilylamides. Each potassium in 2 is ligated by an η4-toluene, two bridging nitrogen atoms, and an η2-phenyl, an η1-phenyl, and an η1-methyl group. KN(SiMe2Ph)2 crystallizes from toluene in the presence of 18-crown-6 to make the monometallic complex (18-crown-6)KN(SiMe2Ph)2, 3, in which [N(SiMe2Ph)2]1- functions as a simple monodentate ligand through nitrogen. The reaction of HN(SiMe2Ph) 2 with NaH in THF at reflux for 2 days generates Na[N(SiMe 2Ph)2], 4, which crystallizes as the solvated dimer {(THF)Na[μ-η1:η1-N(SiMe2Ph) 2]}2, 5. A lanthanide metallocene derivative of [N(SiMe2Ph)2]1- was obtained by reaction of K[N(SiMe2Ph)2] with [(C5Me5) 2La]-[(μ-Ph)2BPh2]. Crystals of (C 5Me5)2La[N(SiMe2Ph)2], 6, show agostic interactions between lanthanum and methyl groups of each silyl substituent. The [N(SiMe3)2]1- analogue of 3, (18-crown-6)KN(SiMe3)2, 7, was also structurally characterized for comparison.
