Dimethyl (1-diazo-2-oxopropyl)phosphonate can be used as a reagent for the synthesis of: Ethynyl compounds (alkynes) from aldehydes. Isoquinoline and pyridine N-oxides by cyclization with oximes in the presence of Rh catalyst. Dimethyl(diazomethyl)phosphonate through methanolysis, which is further employed as a reagent in the synthesis of enol ethers or alkynes. Five-member heterocyclic scaffolds of pyrazoles, triazoles, and oxazoles via cycloaddition reaction and multicomponent reaction. Dimethyl (1-diazo-2-oxopropyl)phosphonate can be used as a reagent for the synthesis of: Ethynyl compounds (alkynes) from aldehydes. Isoquinoline and pyridine N-oxides by cyclization with oximes in the presence of Rh catalyst. Dimethyl(diazomethyl)phosphonate through methanolysis, which is further employed as a reagent in the synthesis of enol ethers or alkynes. Five-member heterocyclic scaffolds of pyrazoles, triazoles, and oxazoles via cycloaddition reaction and multicomponent reaction.