Frustrated Lewis pair catalyzed hydrosilylation and hydrosilane mediated hydrogenation of fulvenes
Sergej Tamke1, Constantin-G Daniliuc, Jan Paradies
1Karlsruhe Institute of Technology, Institute of Organic Chemistry, Fritz-Haber-Weg 6, 76131, Karlsruhe, Germany. jan.paradies@kit.edu.
Abstract:
The frustrated Lewis pair (FLP) mediated hydrosilylation of pentafulvenes is described yielding allyl silanes with high regioselectivity in excellent yields. While phenyl substituted allyl silanes undergo B(C6F5)3-mediated rearrangement to vinyl silanes, dimethyl derivatives experience FLP-catalyzed hydrogenation followed by an unprecedented protodesilylation. This observation allowed the metal-free hydrogenation of 6,6-dimethylfulvene to iso-propyl cyclopentene according to a FLP-catalyzed triple domino reaction consisting of hydrosilylation, hydrogenation and protodesilylation. The mechanisms were investigated by deuteration experiments.
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