Diazo Transfer From Nitrous Oxide Employing Phosphorus Ylides

The synthesis of diazo-containing molecules traditionally relies on hazardous reagents such as azides or hydrazines, which restrict their practicality, especially for large-scale applications. Herein, we report a novel strategy for diazo transfer utilizing nitrous oxide (N₂O) fixation at a phosphorus ylide. This method enables the efficient synthesis of valuable organic building blocks under mild, hydrazine-free conditions. The one-pot approach provides a safer and more practical route to diazo compounds, which can be trapped directly. This facile pathway gives access to a broad range of dinitrogen-containing compounds, including 1,2,3-triazolo heterocycles and (macrocyclic) aldazines. We additionally disclose a new phthalazine heterocycle synthesis utilizing bis-P-ylides and N₂O. Both intra- and intermolecular trapping are investigated, which establishes N₂O fixation as a powerful tool in synthetic methodology.