Catalyst-Free Annulation of Acylethynylpyrroles with 1-Pyrrolines: A Straightforward Access to Tetrahydrodipyrrolo[1,2- a :1',2'- c ]imidazoles.
Ludmila A OparinaKseniya V BelyaevaNikita A KolyvanovIgor A UshakovMaxim D GotskoLyubov' N SobeninaAlexander V VashchenkoBoris A TrofimovPublished in: The Journal of organic chemistry (2022)
Acylethynylpyrroles undergo facile (rt, MeCN or MeOH, 24-72 h) catalyst-free annulation with 1-pyrrolines to afford acylmethylenetetrahydrodipyrrolo[1,2- a :1',2'- c ]imidazoles in up to 93% yield and 90% E -stereoselectivity of the olefin moiety.