Organocatalyzed Asymmetric Pictet-Spengler Reactions

The Pictet-Spengler reaction is a century old technique for the construction of aza-cycles, which has been extensively researched through organocatalytic methods over the past two decades. The asymmetric variant of this reaction has gained considerable attention because the enantioenriched poly heterocycles accessed through the process are prevalent in natural products and bioactive moleculesPrime focus of this review is the systematic and chronological assembly of enantioselective P-S reaction catalyzed by different types of organocatalysts. Mechanistic approaches to rationalize the asymmetric induction on the products are an additional flavor of the article. Importance of this conventional reaction has been justified by the synthesis of different biologically and naturally relevant compounds which have been highlighted in this review as well.