2,3-Pyrazinedicarboxylic acid
Structural formula
| Business number | 020C |
|---|---|
| Molecular formula | C6H4N2O4 |
| Molecular weight | 168.11 |
| label |
Pyrazine-2,3-dicarboxylic acid, p-Diazepine-2,3-dicarboxylic acid, 1,4-pyridazine-2,3-dicarboxylic acid, Pyrazine-2,3-dicarboxylic acid, 2,3-dicarboxypyrazine, Heterocyclic compounds |
Numbering system
CAS number:89-01-0
MDL number:MFCD00006131
EINECS number:201-875-3
RTECS number:UQ2500000
BRN number:147982
PubChem number:24898680
Physical property data
1. Properties: Those containing 2 molecules of crystal water are columnar crystals. Loss of crystallization water at 100°C.
2. Density (g/mL, 25/4℃): Undetermined
3. Relative vapor density (g/mL, air=1): Undetermined
4. Melting point (ºC): 183~185 (carbon dioxide is released at the same time)
5. Boiling point (ºC, normal pressure): Undetermined
6. Boiling point (ºC) ,5.2kPa): Not determined
7. Refractive index: Not determined
8. Flash point (ºC): Not determined
9. Specific rotation (º): Not determined
10. Autoignition point or ignition temperature (ºC): Not determined
11. Vapor pressure (kPa, 25ºC): Not determined
12. Saturated vapor pressure (kPa, 60ºC): Undetermined
13. Heat of combustion (KJ/mol): Undetermined
14. Critical temperature (ºC): Undetermined
15. Critical pressure (KPa): Undetermined
16. Log value of oil-water (octanol/water) partition coefficient: Undetermined
17. Explosion upper limit (%, V/V): Undetermined
18. Explosion lower limit (%, V/V): Undetermined
19. Solubility: Easily soluble in Water, soluble in methanol, acetone and ethyl acetate, slightly soluble in ethanol, ether, chloroform, benzene and petroleum ether.
Toxicological data
None
Ecological data
None
Molecular structure data
1. Molar refractive index: 36.29
2. Molar volume (cm3/mol): 100.9
3. Isotonic specific volume (90.2K ): 319.8
4. Surface tension (dyne/cm): 100.7
5. Polarizability (10-24cm3): 14.38
Compute chemical data
1. Reference value for hydrophobic parameter calculation (XlogP): None
2. Number of hydrogen bond donors: 2
3. Number of hydrogen bond acceptors: 6
4. Number of rotatable chemical bonds: 2
5. Number of tautomers: none
6. Topological molecule polar surface area 100
7. Number of heavy atoms: 12
8. Surface charge: 0
9. Complexity: 184
10. Number of isotope atoms: 0
11. Determine the number of atomic stereocenters: 0
12. Uncertain number of atomic stereocenters: 0
13. Determine the number of chemical bond stereocenters: 0
14. Number of uncertain chemical bond stereocenters: 0
15. Number of covalent bond units: 1
Properties and stability
Harmful Substance. Do not breathe dust and prevent skin and eye contact.
Storage method
This product should be kept sealed.
Synthesis method
Using benzopyrazine as raw material, it is obtained by oxidation with potassium permanganate. First, put water and benzopyrazine into the reaction pot, add potassium permanganate evenly under stirring, keep the temperature at 68-70°C for 2 hours, and measure the end point. Leave it overnight, absorb the supernatant, add water to the lower layer, stir, heat to 80°C and filter, concentrate the supernatant and filtrate with a thin film evaporator, then take out and neutralize with hydrochloric acid to pH=2, and precipitate monopotassium pyrazinedicarboxylate Salt, cool, and filter at 25°C. Add the filter cake to hydrochloric acid, stir and heat until it is completely dissolved, cool and crystallize below 15°C, filter, wash with a little ethanol, and spin dry to obtain a crystalline product. Based on benzopyrazine, the yield is 70%.
Purpose
This product is an intermediate of the anti-tuberculosis drug pyrazinamide.