5-Substituted dipyrranes: synthesis and reactivity

Dipyrranes constitute important building blocks in the synthesis of porphyrins, corroles, chlorins, calix[4]pyrroles, porphodimethenes, BODIPY dyes and dipyrrinato complexes. This tutorial review describes the overall progress made in the last twenty years in this field, mainly focusing on the most practical and useful synthetic methodologies and offers a critical comparison of various conditions reported in the literature. This review also deals with the reactivity of 5-substituted dipyrranes presenting the scope of their reactions with electrophiles.