Superacidic Aluminum Azido Species: Precursor to Triazolyl Dimers, Trimers and Tetramers

Abstract

The aluminum-azido species (Me3SiN3)Al(C6F5)3 thermally converts to [(C6F5)2Al(-N3)]2 2. Further reactions with Me3SiN3 afforded [(C6F5)2Al(-N3)2]3Al which contains an unique four Al centers bound to six bridging azides. Compound 2 is shown to be a Lewis superacid both experimentally and theoretically, forming dimeric products in reactions with diphenylphosphine oxide or tetrahydrofuran and a monomeric adduct with an NHC donor. Compound 2 also undergoes “click” reactions with alkynes to give dimeric, trimeric and tetrameric products depending on the nature of the substitution on the alkyne, whichh demonstrates the ability of the reagent to control the nature of the agregation.