| Melting Point | 72–75°C (lit.) |
| Linear Formula | H2NNHCOCH2CO2C2H5 |
| Molecular Weight | 146.14 g/mol |
| SMILES String | CCOC(=O)CC(=O)NN |
| Assay | 97% |
| CAS Number | 30866-24-1 |
| Empirical Formula | C5H10N2O3 |
| NACRES | NA.22 |
| PubChem Substance ID | 24863594 |
| UNSPSC Code | 12352100 |
| MDL Number | MFCD00134484 |
| InChI | 1S/C5H10N2O3/c1-2-10-5(9)3-4(8)7-6/h2-3,6H2,1H3,(H,7,8) |
| InChI Key | HCPOCMMGKBZWSJ-UHFFFAOYSA-N |
| PubChem CID | 252897 |
| Functional Groups | Amine, ester, hydrazine |
| Form | Solid |
| Applications | Pyrazole and dihydropyrazole synthesis: reacts with 4-alkoxy-1,1,1-trifluoro-3-alken-2-ones, by conventional heating or under microwave irradiation, to give 4,5-dihydro-1H-pyrazoles carrying a trifluoromethyl group. Fluorinated pyrazolines are a popular scaffold in agrochemical and medicinal chemistry screening sets. |
Ethyl malonyl hydrazine is the mono-hydrazide of malonic acid mono-ethyl ester. One carbonyl is an ethyl ester; the other is an acyl hydrazide, –C(=O)NHNH2. Its molecular formula is C5H10N2O3 (linear formula H2NNHCOCH2CO2C2H5) and its molecular weight is 146.14 g/mol. Sigma-Aldrich’s listing describes it as a solid melting at 72–75 °C and classifies its functional groups as amine, ester and hydrazine.
Because the methylene group sits between two electron-withdrawing carbonyls, it is acidic enough to take part in Knoevenagel-type condensations and alkylations, while the hydrazide nitrogen is a soft, nucleophilic site. Few reagents of this size put an ester, an enolisable CH2 and a hydrazide into one molecule, which is why it appears so often in heterocycle route design.
In synthetic chemistry its main role is as a hydrazine-bearing synthon for five- and six-membered nitrogen heterocycles. Reaction with trifluoromethylated enones delivers dihydropyrazoles; reaction with 1,3-dicarbonyl partners can furnish pyrazolones and pyrazole carboxylates; and further cyclisation onto the ester gives fused pyrazolopyridazine skeletons. These cores are common in fungicide, herbicide and kinase-inhibitor research, so the compound is often purchased as a late-stage or mid-stage intermediate by teams in agrochemical and pharmaceutical R&D.
In the laboratory it is also a convenient way to introduce an acylhydrazone linkage. Condensation with an aldehyde or ketone is usually quick and clean, and the resulting acylhydrazones are used as ligands, as dynamic covalent linkers and as screening fragments.
The reference grade is 97% assay. Buyers planning multi-step routes should ask for lot-specific purity data on the Certificate of Analysis, because residual hydrazine-containing by-products from manufacture can interfere with sensitive condensations. Acyl hydrazides react with ketones, so avoid acetone for rinsing glassware or cleaning transfer lines that will contact the material. Keep the container tightly closed, in a cool, dry place away from oxidisers and strong acids; the product is classed as a combustible solid for storage purposes.
Based on Sigma-Aldrich’s verified classification for the reference listing (378909).
Handle in a ventilated area or fume hood, avoid generating dust, and wash hands thoroughly after use. As with any hydrazine derivative, avoid contact with strong oxidisers and keep the material away from heat and ignition sources.
