1319082-50-2Relevant academic research and scientific papers
A unique transition metal-stabilized silicon cation
Muether, Kristine,Froehlich, Roland,Mueck-Lichtenfeld, Christian,Grimme, Stefan,Oestreich, Martin
, p. 12442 - 12444 (2011)
Trivalent silicon cations are exceptionally strong electron pair acceptors that react, either desired or undesired, with almost any σ and π basic molecule. One way of intramolecular attenuation of the Lewis acidity of these superelectrophiles is by installation of a ferrocene unit at the electron-deficient silicon atom. While well-understood for isoelectronic α-ferrocenyl-substituted carbenium ions and also boranes, the stabilizing interactions between the ferrocene backbone and a positively charged silicon atom are not clear due to the challenge of crystallizing such cations. The structural characterization of our ferrocene-stabilized silicon cation now reveals an unprecedented bonding motif different from its analogues. An extreme dip angle of the silicon atom toward the iron atom is explained by two three-center-two-electron (3c2e) bonds through participation of both the upper and the lower aromatic rings of the ferrocene sandwich structure. The positive charge is still localized at the silicon atom that also retains a quasi-planar configuration.
Taming the silylium ion for low-temperature diels-alder reactions
Klare, Hendrik F. T.,Bergander, Klaus,Oestreich, Martin
, p. 9077 - 9079 (2010/03/03)
Some like it hot: A novel silicon-based Lewis acid having a trivalent silicon cation stabilized by an electron-rich transition metal as the "hot" Lewis acidic site catalyzes challenging Diels-Alder reactions at low temperatures with excellent reaction rat
