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Published on: September 8, 2013
Silylium-Ion-Promoted Hydrosilylation of Aryl-Substituted Allenes: Interception by Cyclization of the Allyl-Cation
Supriya Rej1, Hendrik F T Klare1, Martin Oestreich1
1Institut für Chemie, Technische Universität Berlin, Straße des 17. Juni 115, 10623 Berlin, Germany.
Abstract:
A trityl-cation-initiated, silylium-ion-promoted hydrosilylation of aryl-substituted allenes is reported. Depending on the hydrosilane-to-initiator ratio, the hydrosilylation can be intercepted by an intramolecular electrophilic aromatic substitution or a Nazarov electrocyclization of an allyl-cation intermediate in the form of its endo isomer. By this, the selective formation of either the conventional 1,2-hydrosilylation product (vinylsilane) or a cyclized product (silylated indane) can be controlled.
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