Anomalous electrophilic substitution reactions in 3,3′-linked dipyrromethanes
The 3,3′-linked dipyrromethane 5 was synthesized by the self-condensation of hydroxymethylpyrrole 4; along with 5, a minor by-product was the novel tripyrrane 7. Vilsmeier formylation of 5 unexpectedly afforded the formylpyrrole 6 instead of the diformyldipyrromethane 8. Likewise, acylation of 5 gave acetylpyrrole 9 as the major product. A mechanism is proposed for this novel 3,3′-dipyrromethane acylation(formylation)/fragmentation reaction.
Publication Source (Journal or Book title)
Leung, S., Nguyen, L., & Smith, K. (1996). Anomalous electrophilic substitution reactions in 3,3′-linked dipyrromethanes. Heterocyclic Communications, 2 (1), 9-12. https://doi.org/10.1515/HC.19220.127.116.11