http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-761820-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_283e7be7af9e30bb8f4981a90b12714f |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07C67-39 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07C69-82 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C67-39 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C69-82 |
| filingDate | 1954-07-21-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1956-11-21-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-761820-A |
| titleOfInvention | Process for the production of terephthalic acid dimethyl ester |
| abstract | Dimethyl terephthalate is prepared by reacting p-xylylene dichloride with nitric acid of medium concentration (40-65 per cent, preferably 50 per cent) in the presence of methyl alcohol. Preferably the nitric acid is added to the p-xylylene dichloride and the mixture is heated to a temperature above 100 DEG C. The methyl alcohol may be added dropwise during this heating or methyl alcohol vapour may be passed through the reaction mixture. The yield is increased by adding phosphoric acid or sodium, potassium or calcium biphosphate to the reaction mixture, and also passing hydrogen chloride through the reaction mixture. In examples: (1) hydrogen chloride gas is passed through a heated mixture of p-xylylene di-chloride and aqueous nitric acid to which methanol is added dropwise, dimethyl terephthalate together with small amounts of the methyl esters of p-aldehydobenzoic and p-chloromethylbenzoic acids being obtained; (2) as in (1) but adding phosphoric acid to the reaction mixture; (3) as in (1) but passing methanol vapour into the reaction mixture. |
| priorityDate | 1953-08-03-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 32.