188599-46-4Relevant articles and documents
Expanding the steric coverage offered by bis(amidosilyl) chelates: Isolation of low-coordinate N-heterocyclic germylene complexes
Liew, Sean K.,Al-Rafia, S. M. Ibrahim,Goettel, James T.,Lummis, Paul A.,McDonald, Sean M.,Miedema, Leah J.,Ferguson, Michael J.,McDonald, Robert,Rivard, Eric
experimental part, p. 5471 - 5480 (2012/07/01)
The synthesis and coordination chemistry of a series of dianionic bis(amido)silyl and bis(amido)disilyl, [NSiN] and [NSiSiN], chelates with N-bound aryl or sterically modified triarylsilyl (SiAr3) groups is reported. In order to provide a consistent comparison of the steric coverage afforded by each ligand construct, various two-coordinate N-heterocyclic germylene complexes featuring each ligand set were prepared and oxidative S-atom transfer chemistry was explored. In the cases where clean oxidation transpired, sulfido-bridged centrosymmetric germanium(IV) dimers of the general form [LGe(μ-S)]2 (L = bis(amidosilyl) ligands) were obtained in lieu of the target monomeric germanethiones with discrete Ge=S double bonds. These results indicate that the reported chelates possess sufficient conformational flexibility to allow for the dimerization of LGe=S units to occur. Notably, the new triarylsilyl groups (4-RC6H4)3Si- (R = tBu and iPr) still offer considerably expanded degrees of steric coverage relative to the parent congener, -SiPh3, and thus the use of substituted triarylsilyl groups within ligand design strategies should be a generally useful concept in advancing low-coordination main group and transition-metal chemistry.
