Highly efficient synthesis of tert-butyl esters using (Boc)2O under solvent/base-free electromagnetic milling conditions: a new reaction model†

A novel and efficient method has been developed for the synthesis of tert-butyl esters using (Boc)₂O as the tert-butyl source, facilitated by electromagnetic milling. This green and sustainable approach is solvent-free, base-free, and operates without the need for additional heating, making it highly appealing for eco-friendly synthesis. The entirely neutral reaction environment proves particularly advantageous for synthesizing or modifying sensitive drug molecules, especially in late-stage functionalization. In this process, ferromagnetic rods, used as grinding media, become magnetized and charged under a high-speed rotating magnetic field. This magnetization plays a crucial role in bond activation by coordinating with the charged ferromagnetic rods, introducing a novel mechanism for bond activation that could inspire further research in this emerging field.