2 research outputs found
Substrate-Controlled Synthesis of Spirocyclopropylpyrazolones and Bicyclic 4,5-Dihydropyrazoles from 1,2-Diaza-1,3-dienes with Sulfur Ylides
Substrate-controlled reactions have
been developed for the synthesis
of spirocyclopropylpyrazolones and bicyclic 4,5-dihydropyrazoles
from 1,2-diaza-1,3-dienes and sulfur ylides. These protocols were
carried out under mild reaction conditions without any additives in
generally moderate to good yields. Plausible mechanisms for the transformations
were proposed
Tuning the Annulation Reactivity of Vinyl Azides and Carbazates: A Divergent Synthesis of Aza-pyrimidinones and Imidazoles
A divergent
cascade annulation has been developed using readily
available vinyl azides and carbazates with a wide range of substituents.
Vinyl azides were successfully applied as bifunctional partners to
prepare aza-pyrimidinones via 6-ring closure with carbazates as well
as to construct polyfunctionalized imidazoles via 5-ring closure with <i>N</i>-substituted carbazates. The aza-heterocycles were obtained
with high levels of chemoselectivity and excellent yields