B2(OH)4-Mediated Reductive Transamidation of N-Acyl Benzotriazoles with Nitro Compounds En Route to Aqueous Amide Synthesis

We herein developed a reductive transamidation reaction between N-acyl benzotriazoles (AcBt) and organic nitro compounds or NaNO2 under mild conditions. This protocol employed the stable and readily available B2(OH)4 as the reducing agent and H2O as the ideal solvent. N-Deuterated amides can be synthesized when conducting the reaction in D2O. A reasonable reaction mechanism involving bond metathesis between the AcBt amide and amino boric acid intermediate was proposed to explain the unique nature of AcBt.