Cooperative N–H bond activation by amido-Ge(ii) cations
Zhou, X., Vasko, P., Hicks, J., Fuentes, M. A., Heilmann, A., Kolychev, E. L., & Aldridge, S. (2020). Cooperative N–H bond activation by amido-Ge(ii) cations. Dalton Transactions, 49(27), 9495-9504. https://doi.org/10.1039/d0dt01960g
Published inDalton Transactions
DisciplineEpäorgaaninen ja analyyttinen kemiaNanoscience CenterInorganic and Analytical ChemistryNanoscience Center
© The Royal Society of Chemistry 2020
N-heterocyclic carbene (NHC) and tertiary phosphine-stabilized germylium-ylidene cations, [R(L)Ge:]+, featuring tethered amido substituents at R have been synthesized via halide abstraction. Characterization in the solid state by X-ray crystallography shows these systems to be monomeric, featuring a two-coordinate C,N- or P,N-ligated germanium atom. The presence of the strongly Lewis acidic cationic germanium centre and proximal amide function allows for facile cleavage of N–H bonds in 1,2-fashion: the products resulting from reactions with carbazole feature a tethered secondary amine donor bound to a three-coordinate carbazolyl-GeII centre. In each case, addition of the components of the N–H bond occurs to the same face of the germanium amide function, consistent with a coordination/proton migration mechanism. Such as sequence is compatible with the idea that substrate coordination via the pπ orbital at germanium reduces the extent of N-to-Ge π donation from the amide, thereby enhancing the basicity of the proximal N-group. ...