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