English Synonyms
4-PYRIDINECARBOXYLICACIDFORSYNTHESIS;Isonicotinicaci;66kDaneurofilamentprotein;ANTI-INA(ALPHAINTERNEXIN)(CENTER)antibodyproducedinrabbit;NEF5;Neurofilament5;Pyridine-4-carboxylicacid,4-Carboxypyridine;Isonicotinicacid,CP,98%
Isonicotinic Acid Properties
| Melting Point | ≥300 °C (lit.) |
| Boiling Point | 260 °C (15 mmHg) |
| Density | 1,47g/cm |
| Refractive Index | 1.5423 (estimate)
|
| Flash Point | 260°C/15mm |
| Storage Conditions | No Restrictions. |
| Acidity Coefficient (pKa) | 4.96(at 25℃) |
| Form | Powder |
| Color | Yellow to Tan |
| PH | 3-4 (6g/l, H2O, 20℃)(saturated solution) |
Isonicotinic Acid Usage and Synthesis Method
Use
Isonicotinic acid is a widely used intermediate, mainly used as a raw material for first-line anti-tuberculosis drugs such as isoniazid (remifen), terfenadine and isonicotinate, and can also be used as an anti-corrosion agent, electroplating additive, photosensitive resin stabilizer, polyvinyl chloride heat stabilizer and non-ferrous metal flotation agent, etc. Isoniazid can be prepared by condensing isoniazid with hydrazine hydrate and melting and dehydrating. Isoniazid has a good antibacterial effect on Mycobacterium tuberculosis, good efficacy, small dosage, and relatively low toxicity. It is used for the progressive stage, dissolution and dissemination stage, and absorption improvement stage of various types of pulmonary tuberculosis, and can also be used for tuberculous meningitis and other extrapulmonary tuberculosis, etc. The preparations include tablets and injections.
Synthesis
Isonicotinic acid can be used as a pharmaceutical intermediate. There are many methods for synthesizing isonicotinic acid, which are mainly divided into oxidation method, hydrolysis method and biocatalysis method. Among them, the oxidation method is divided into traditional chemical oxidation methods such as potassium permanganate oxidation method, nitric acid oxidation method, catalytic air oxidation method, ozone oxidation method and electrochemical oxidation method.
Production Method
The preparation method comprises the following steps: heating the reaction tower to 260°C, activating the catalyst vanadium pentoxide for 12 hours, preheating the reaction tower to 255-260°C, adding 4-methylpyridine, and mixing the mixture with steam and air after preheating and gasification into the oxidation tower; collecting the isonicotinic acid powder generated by the reaction through cyclone separation; condensing the reaction tail gas and cyclically absorbing it with dilute hydrochloric acid to recover the unreacted 4-methylpyridine and the entrained isonicotinic acid.
It is prepared by continuous oxidation using 4-methylpyridine as raw material and vanadium pentoxide as catalyst. The purity of industrial isonicotinic acid is above 95%, and the yield of the above method is 70-75%. 1070 kg of 4-methylpyridine is consumed per ton of product.
