http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-579505-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_d202e9e866984fe229f6facc38f1d740 |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07D213-803 |
| classificationIPCAdditional | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07D213-79 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07D213-803 |
| filingDate | 1944-05-06-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1946-08-06-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-579505-A |
| titleOfInvention | Improvements in or relating to the manufacture of pyridine carboxylic acids |
| abstract | Pyridine carboxylic acids are produced by heating for 1 to 3 hours at between 150 DEG and 250 DEG C. a mixture of a pyridine hydrohalide and the betaine of an N-alkyl pyridine carboxylic acid having the general formula <FORM:0579505/IV/1> wherein R represents an alkyl group. An optimum temperature of 200 DEG C. and heating period of approximately 2 hours is specified and pyridine hydrochloride is the hydrohalide preferred, but other pyridine hydrohalides, e.g. the hydrobromide may be used, resulting in lower yields. In examples: (1) trigonelline admixed with pyridine hydrochloride is heated in an open vessel at about 200 DEG C. for nearly 3 hours and impure nicotinic acid is isolated by treating a neutralised aqueous solution of the reaction products with a soluble copper salt to precipitate copper nicotinate which is decomposed in aqueous suspension in presence of formic acid, by treatment with hydrogen sulphide; a mixture of trigonelline (88 per cent pure) and pyridine hydrochloride is heated (2) for about 1 hour, and (3) for about 2 hours at approximately 200 DEG C., being subsequently treated as in (1) to yield substantially pure nicotinic acid; (4) trigonelline (89 per cent pure), admixed with pyridine hydrobromide, is heated for about 2 hours at approximately 200 DEG C., and the product is isolated as in (1). The Specification as open to inspection under Sect. 91 comprises also the cases wherein R, in the specified general formula, may represent an aralkyl or aryl group. This subject-matter does not appear in the Specification as accepted. |
| priorityDate | 1943-05-11-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 33.