A Flash Conversion to Aromatic Azo Compounds Expedited by Hydrazine–Trifluoroacetate Hydrogen Bonding

Aromatic azo compounds are very useful chemicals, but rapid and safe synthetic methods for preparing these compounds are underexplored. An extremely fast reaction was developed to prepare aromatic azo compounds from commercially available quinones and aryl hydrazinium chloride salts. The reactions could be completed within 2 min, in the presence of sodium trifluoroacetate under ambient conditions. A hydrazine-trifluoroacetate hydrogen bonding complex likely inhibited byproducts and greatly accelerated the reaction. The overall procedure is extremely simple and does not require sophisticated synthetic organic equipment and techniques.