24919-78-6Relevant articles and documents
Assembly of 1,2,3,4-Tetrahydropyrrolo[1,2- a]pyrazines via the Domino Reaction of 2-Imidazolines and Terminal Electron-Deficient Alkynes
Festa, Alexey A.,Golantsov, Nikita E.,Golubenkova, Alexandra S.,Varlamov, Alexey V.,Voskressensky, Leonid G.
, (2022/02/05)
The transformation of 2-imidazolines into 1,2,3,4-tetrahydropyrrolo[1,2-a]pyrazines has been realized. A pseudo-three-component reaction of 2-imidazolines with terminal electron-deficient alkynes (2 equiv) first generates imidazolidines, containing an N-vinylpropargylamine fragment. The latter can then undergo a base-catalyzed domino aza-Claisen rearrangement/cyclization reaction sequence, simultaneously constructing pyrrole and pyrazine rings. The process works in a broad substrate scope, delivering pyrrolo[1,2-a]pyrazines in good to excellent yields (45-90%). This two-step approach can be carried out in a one-pot fashion without a noticeable decrease in yield. Remarkably, a three-component protocol for the introduction of two different alkynes has been also developed.
One-pot triflic anhydride-mediated synthesis of 1,2-disubstituted 2-imidazolines from N-(2-haloethyl)amides and amines
Ellsworth, Alyssa A.,Magyar, Christina L.,Hubbell, Grace E.,Theisen, Chelsea C.,Holmes, Daniel,Mosey, R. Adam
, p. 6380 - 6389 (2016/09/23)
A one-pot synthesis of 1,2-disubstituted 2-imidazolines from N-(2-haloethyl)amides has been developed. The reaction affords high yields of diverse 1,2-disubstituted 2-imidazolines from triflic anhydride-mediated dehydration of amides followed by installat
