1356536-87-2Relevant articles and documents
Evidence for a Single Electron Shift in a Lewis Acid-Base Reaction
Dong, Zhaowen,Cramer, Hanna H.,Schmidtmann, Marc,Paul, Lucas A.,Siewert, Inke,Müller, Thomas
, p. 15419 - 15424 (2018)
The Lewis acid-base reaction between a nucleophilic hafnocene-based germylene and tris-pentafluorophenylborane (B(C6F5)3) to give the conventional B-Ge bonded species in almost quantitative yield is reported. This reaction is surprisingly slow, and during its course, radical intermediates are detected by EPR and UV-vis spectroscopy. This suggests that the reaction is initiated by a single electron-transfer step. The hereby-involved germanium radical cation was independently synthesized by oxidation of the germylene by the trityl cation or strong silyl-Lewis acids. A perfluorinated tetraarylborate salt of the radical cation was fully characterized including an XRD analysis. Its structural features and the results of DFT calculations indicate that the radical cation is a hafnium(III)-centered radical that is formed by a redox-induced electron transfer (RIET) from the ligand to the hafnium atom. This valence isomerization slows down the coupling of the radicals to form the polar Lewis acid-base product. The implications of this observation are briefly discussed in light of the recent finding that radical pairs are formed in frustrated Lewis pairs.
A new synthesis of triarylsilylium ions and their application in dihydrogen activation
Schaefer, Andre,Reissmann, Matti,Schaefer, Annemarie,Saak, Wolfgang,Haase, Detlev,Mueller, Thomas
, p. 12636 - 12638 (2012/02/15)
Well-shuffled: An unexpected substituent distribution reaction via alkyldiarylsilylium ions leads to a distribution of substituents. Starting from alkyldiaryl silanes, this reaction provides a facile synthetic approach to sterically highly hindered triarylsilylium ions. These silylium ions can be applied in dihydrogen activation reactions. Copyright
