Wu, QianRoy, AvijitIrran, ElisabethQu, Zheng-WangGrimme, StefanKlare, Hendrik F. T.Oestreich, Martin2020-02-132020-02-132019-10-231433-7851https://depositonce.tu-berlin.de/handle/11303/10760http://dx.doi.org/10.14279/depositonce-9655A metal‐free, intermolecular syn‐addition of hexamethyldisilane across simple alkenes is reported. The catalytic cycle is initiated and propagated by the transfer of a methyl group from the disilane to a silylium‐ion‐like intermediate, corresponding to the (re)generation of the silylium‐ion catalyst. The key feature of the reaction sequence is the cleavage of the Si−Si bond in a 1,3‐silyl shift from silicon to carbon. A central intermediate of the catalysis was structurally characterized by X‐ray diffraction, and the computed reaction mechanism is fully consistent with the experimental findings.en540 Chemie und zugeordnete Wissenschaftenalkenesdensity functional calculationshomogeneous catalysissilylium ionsSi@Si activationArticle1521-3773