Recent Advances in Synthetic Methods for 2H‐Pyrroles

Abstract The compound, 2 H ‐pyrrole, is a key scaffold contained in natural products, bioactive compounds, pharmaceuticals, and organic functional materials. However, the development of efficient synthetic strategies for 2 H ‐pyrroles is challenging. This is because 2 H ‐pyrroles, owing to their nonaromatic nature, are easily converted into the thermodynamically more stable 1 H ‐pyrroles. Recently, efficient and straightforward synthetic strategies for 2 H ‐pyrroles have been developed, including the dearomatization of 1 H ‐pyrrole, oxidation of pyrrolines or pyrrolidines, ring construction via catalytic cycloaddition, and rearrangement of 3 H ‐pyrroles. In this review, we summarize the progress in the research on 2 H ‐pyrrole synthesis since 2000 and briefly discuss the synthesis reaction mechanisms.