| Names | |
|---|---|
| Preferred IUPAC name Piperazinetetrone | |
| Other names 2,3,5,6-Piperazinetetrone | |
| Identifiers | |
3D model (JSmol) | |
| ChemSpider | |
PubChem CID | |
| UNII | |
CompTox Dashboard (EPA) | |
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| Properties | |
| C4H2N2O4 | |
| Molar mass | 142.070 g·mol−1 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
Tetraketopiperazine is a chemical compound with a molecule containing a six member heterocyclic ring with two nitrogen atoms. Each carbon is doubly bonded to oxygen. [1]
Reacting sodium oxamate (the sodium salt of oxamic acid) with hydrochloric acid yields some tetraketopiperazine. A higher yield results from reacting ethyl oxalate with sodium ethoxide. [1] Yet another way to make tetraketopiperazine is a condensation of oxamide with ethyl oxalate with sodium ethoxide present.
Excessive nitration of 2,6-diaminopyrazine ends up with tetraketopiperazine. [2]
The nitrogen atoms in tetraketopiperazine are slightly acidic losing their hydrogen atoms as ions. Salts of tetraketopiperazine exist. Tetraketopiperazine reacts with sodium bicarbonate to yield a monosodium salt. A disodium salt results from reaction with sodium hydroxide or sodium alkoxide. These are likely to be tautomeric with a hydrogen moving to an oxygen atom. Potassium salts also exist. A monosilver salt can be made from a silver compound and a dissolved tetraketopiperazine potassium salt. Ammonia and mercury salts of tetraketopiperazine also exist. Tetraketopiperazine also can form a monohydrazone. [1]
Reduction of tetraketopiperazine yields trikeopiperazine and then 2,5-diketopiperazine. Glyoxalic acid and oxamide are side products. [3]
When heated tetraketopiperazine does not melt, but turns black at 250°C. [1]
Tetraketopiperazine is slightly soluble in water and more so in boiling acetic acid. The solid form has monoclinic prismatic crystals. [1]
pKa is 4.8 and the second pKa2 is 8.2. [3]