Novel 4-(Trimethylsilyl)aminoalkanes and 4-(Trimethylsilyl)aminoalk-2-enes, via a 1,5-Hydride Shift, in the Reaction of α-Unsaturated Silanes with Aminomethylbenzotriazoles

1-[(Dialkylamino)methyl]benzotriazoles react with allyl- and propargyltrimethylsilanes in the presence of aluminum chloride to give, as major products, the unexpected 4-(trimethylsilyl)aminoalkanes and 4-(trimethylsilyl)aminoalk-2-enes, respectively. The products thus obtained are unusual and could be explained by a 1,5-hydride shift occurring in the formation of the initial (and expected) carbocation intermediate. When such a migration is not possible, the resulting products in the reaction are the usual homoallylamines or α-allenylamines. To our knowledge 4-(trimethylsilyl)aminoalkanes and 4-(trimethylsilyl)aminoalk-2-enes have not been previously reported.