Synthesis and cycloaddition reactions of pyrrole-fused 3-sulfolenes: A new versatile route to tetrabenzoporphyrins
Pyrrole-fused 3-sulfolenes 2a,b were prepared from the corresponding α,β-unsaturated sulfone 1. These pyrroles undergo thermal extrusion of sulfur dioxide to produce highly reactive o-quinodimethanes which can be trapped in Diels-Alder reactions. The resulting pyrroles are important starting reagents in porphyrin synthesis.
Publication Source (Journal or Book title)
Vicente, M., Tomé, A., Walter, A., & Cavaleiro, J. (1997). Synthesis and cycloaddition reactions of pyrrole-fused 3-sulfolenes: A new versatile route to tetrabenzoporphyrins. Tetrahedron Letters, 38 (20), 3639-3642. https://doi.org/10.1016/S0040-4039(97)00689-8