Propanephosphonic acid anhydride (T3P)​. A benign reagent for diverse applications inclusive of large-​scale synthesis

A review. Propanephosphonic acid anhydride (T3P) is a prevailing coupling and dehydrating agent with many desirable properties which render it a reagent of choice for a plethora of reactions and, befittingly, its application in org. synthesis is rapidly increasing. Since its introduction as a peptide coupling agent in 1980, the realm of applications of T3P expanded. Currently its use showed a broad range of reactions, including condensation, functional group transformation, heterocycles prepn., rearrangements, and catalysis. It offers several advantages over traditional reagents, such as high yield, chem. and optical purity, broad functional group tolerance and easy work-​up. The reagent is attractive for large-​scale synthesis as well, and particularly so for multi-​kilogram scale prepns. of drug mols. This article reviewed the hitherto reported applications of T3P as a reagent in org. synthesis. Focus is also placed on the use of T3P for large-​scale synthesis