http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-809730-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_df7ea45fb29bfca53eee71d4a4ef7311 |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/A23L29-212 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07C67-08 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07C67-39 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07C69-80 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07C69-82 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07C51-265 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C67-39 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/A23L29-212 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C51-265 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C69-82 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C69-80 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C67-08 |
| filingDate | 1957-06-25-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1959-03-04-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-809730-A |
| titleOfInvention | Method of preparing diesters of phthalic acids |
| abstract | The invention comprises a process for the preparation of phthalic acid diesters by the oxidation, possibly under pressure of a mixture of xylene and an ester of toluic acid with a monovalent saturated aliphatic alcohol containing 1-4 C atoms, the proportions by weight of xylene to the ester being from 1 : 3 to 1 : 1, in the presence of oxygen or gases containing free oxygen, between 80 DEG and 250 DEG C., in the presence of an oxidation catalyst, and carrying out the reaction for at least 4 hours until the xylene has been completely converted into toluic acid, and then continuing the oxidation until substantially, the same quantity of toluic acid ester has been oxidized as toluic acid has been formed by the oxidation of the xylene, esterifying the resulting oxidation mixture with the monohydric saturated aliphatic alcohol corresponding to the ester group of the toluic acid ester used as starting material, and separating the phthalic acid diester thus formed from the remaining toluic acid ester. The remaining toluic acid ester may be subjected to further oxidation together with fresh xylene. Among suitable oxidation catalysts are metal compounds which are soluble in the reaction mixture, e.g. cobalt or manganese salts of fatty acids containing 6-12 C atoms, such as first run fatty acids or cobalt hexanate, or cobalt salts of toluic or benzoic acids. The process may be carried out batchwise or continuously. In the latter case the oxidation is preferably carried out in several aggregate stages, and the oxidation should be started in a phase containing xylene and then continued in a phase-free from xylene. Major quantities of unreacted toluic acid esters should be present at the end of the oxidation, to act as solvents or dispersing agents for the oxidation products obtained. The diesters thus prepared may be separated from the other reaction products by distillation or crystallization. Dif ferent isomers of xylene or toluic acid esters or mixtures thereof may be used as starting materials. Examples are given of the preparation of dimethyl terephthalate from p-xylene and methyl p-toluate, dimethyl isophthalate from m-xylene and methyl-m-toluate, the three dimethyl phthalate isomers from a commercial xylene mixture and the mixture of toluic acid methyl esters, prepared by the esterification of that mixture. Methyl benzoate is also formed as a by-product. |
| isCitedBy | http://rdf.ncbi.nlm.nih.gov/pubchem/patent/CN-108047034-B http://rdf.ncbi.nlm.nih.gov/pubchem/patent/CN-108047034-A http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-6133470-A |
| priorityDate | 1959-05-09-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 58.