Development of a\nTriazinyluronium-Based\nDehydrative\nCondensing Reagent with No Heteroatomic Bonds

A triazinyluronium-based\ndehydrative condensing reagent, 2-(4,6-dimethoxy-1,3,5-triazin-2-yl)-1,1,3,3-tetramethyluronium\nhexafluorophosphate (DMT-TU), has been developed. Unlike commonly\nused guanidinium- and uronium-based reagents, DMT-TU does not contain\nhigh-energy N–N and N–O bonds, reducing its explosivity,\nas suggested by differential scanning calorimetry. Using DMT-TU in\nthe presence of <sup><i>i</i></sup>Pr<sub>2</sub>EtN at\nroom temperature, carboxylic acids and amines were effectively converted\nto their corresponding amides. Additionally, peptide bond formation\nwith DMT-TU exhibited suppressed racemization ratios.