Synthetic Applications of 2-(Azidomethyl)allyltrimethylsilane

Abstract

Starting from commercially available 2-(chloromethyl)-allyltrimethylsilane, the corresponding 2-(azidomethyl)allyl­silane was prepared through reaction with NaN₃. The product was stable upon isolation and storage and could be used for thermal ­cycloaddition of the azido group with alkenes to give allylsilane-containing triazolines or aziridines. This reaction was not accelerated by microwave (MW) dielectric heating, however, the azide fragment undergoes MW-assisted Cu(I)-catalyzed cycloaddition with a range of alkynes (including ynamides). Lewis acid mediated ­Hosomi–Sakurai reaction of the allylsilane with aldehydes was also possible. A one-pot transformation into different triazolo-containing homoallyl alcohols was carried out through a sequence of Cu(I)-catalyzed azide cycloaddition under MW dielectric heating and BCl₃-mediated reaction with aromatic aldehydes.

Key words

microwaves - click chemistry - azides - cycloaddition - allylation

• Reference and notes

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