The Synthesis of Pyrroles from Nitroolefins

The synthesis of pyrroles occupies a key place in synthetic organic chemistry due to the numerous biological properties of pyrrole derivatives, in particular antimicrobial, antibacterial, antifungal, antimalarial, anticancer activities, etc. Therefore, pyrroles serve as building blocks in the creation of potential pharmaceuticals and also serve as the basis for the synthesis of boradipyrromethene dyes. One of the most well-known approaches to the synthesis of pyrroles is the reaction between nitroolefins, 1,3-dicarbonyl compounds, and amines, also known as the Grob-Camenisch reaction. This review is devoted to the historical chronology from the discovery of this transformation dating back to 1950s to the present, and covers the development of various modifications of the above reaction in the synthesis of pyrroles.