Diethyl 3-diazo-2-oxopropylphosphonate is a versatile Horner-Wadsworth-Emmons (HWE) reagent used for the efficient preparation of α,β-unsaturated diazoketones from aldehydes1. These diazoketones serve as multifunctional intermediates in organic synthesis, enabling applications such as asymmetric aziridination, cyclopropanation, and the synthesis of pyrrolidines and γ-butyrolactones. The reagent demonstrates broad substrate scope, reacting with aliphatic, aromatic, and aminoaldehydes to produce α,β-unsaturated diazoketones in high yields under optimized HWE conditions. Diethyl 3-diazo-2-oxopropylphosphonate is a yellow oil stable under inert conditions.

Synonyms: 1-diazo-3-diethoxyphosphorylpropan-2-one; diethyl (3-diazo-2-oxopropyl)phosphonate; 1-diazonio-3-(diethoxyphosphoryl)prop-1-en-2-olate