Copper-Catalyzed Radical Dearomative Azidation: Synthesis of Cyclic α-Quaternary α-Amino Phosphonic Acid Precursors from 2-Phosphonyl-3-Hydroxybenzothiophenes/Benzofurans

Key Points

• The research aims to develop a method for synthesizing cyclic α-quaternary α-amino phosphonic acid precursors using copper catalysis.
• Utilized Cu(II) as a catalyst for azidation process.
• Implemented radical dearomative azidation using azidotrimethylsilane.
• Employed tert-butylhydroperoxide as an oxidant under mild conditions.
• Conducted synthesis with a variety of substrate types.
• Achieved gram-scale synthesis for further development.
• Achieved yields of up to 96% for the synthesis.
• Demonstrated broad substrate scope with successful synthesis of multiple compounds.
• Showed feasibility of further derivatization of the synthesized compounds.