http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-831561-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_dc2f7134efa50484bb359fda73782848 |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07D213-08 |
| filingDate | 1956-06-15-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1960-03-30-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-831561-A |
| titleOfInvention | Process for the manufacture of pyridine and quinoline carboxylic acids |
| abstract | A catalyst used in the oxidation with air of a pyridine homologue, quinoline, or quinoline homologue (see Group IV (b)), comprises a vanadium pentoxide catalyst supported on silica gel and contains also a bisulphate, e.g. potassium bisulphate, a pyrosulphate, e.g. potassium pyrosulphate, sulphuric acid, or phosphoric acid. A suitable catalyst is obtained by adding ammonium vanadate to a mixture of water, potassium sulphate, oxalic acid and concentrated sulphuric acid at about 50 DEG C. while stirring, heating the mixture until a clear blue solution is obtained, pouring the solution on to large pored silica gel, allowing the mixture to stand for about 2 hours at about 50 DEG C., drying the particles at 80 DEG C. and finally roasting in a current of air at about 260 DEG C. and sieving to remove fine particles. Specification 563,274 is referred to.ALSO:A pyridine carboxylic acid or a quinoline carboxylic acid is obtained by passing a mixture of air and a homologue of pyridine, or a mixture of air and quinoline or a homologue thereof, at elevated temperature below 350 DEG C. over a vanadium pentoxide catalyst supported on silica gel, the catalyst used containing a bisulphate, a pyrosulphate, sulphuric acid or phosphoric acid. It is preferred to operate at 260-270 DEG C. and to use a large pored silica gel rather than a finely porous silica gel as support. It is also advantageous to add steam to the air used for oxidation, the amount of steam being in excess of the weight of pyridine homologue or quinoline or quinoline homologue and preferably about 10 times its weight. Preferred space velocities when temperatures below 300 DEG C. are used are about 100 to 400. Examples are given for the oxidation of (1) aldehyde collidine (2-methyl-5-ethyl-pyridine) to nicotinic acid, (2) b -picoline and quinoline respectively to nicotinic acid, and (3) g -picoline to isonicotinic acid. The oxidation is carried out in each case by passing, at elevated temperature, a current of air, which has been previously passed through the pyridine homologue (or quinoline) and water, through a tube containing a catalyst prepared by adding ammonium metavanadate into a mixture of water, potassium sulphate, crystalline oxalic acid and concentrated sulphuric acid at about 50 DEG C. while stirring, heating the mixture until a clear blue solution is obtained, pouring the solution on to large pored silica gel, allowing the mixture to stand at about 50 DEG C. for about 2 hours, drying the particles at 80 DEG C. and finally roasting in a current of air at about 260 DEG C. and sieving to remove fine particles. Specification 563,274 is referred to. |
| isCitedBy | http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-5270469-A |
| priorityDate | 1955-06-16-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 45.