http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-562313-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_8ef57ebc9ba1067fce72f406e3943261 http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_fd9f36df06271a59df790e5021907cdc http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_62cec7685ab07236e11bcaedb225f799 |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07D333-38 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07D333-38 |
| filingDate | 1942-12-22-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1944-06-27-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-562313-A |
| titleOfInvention | Process for manufacture of heterocyclic sulphur compounds |
| abstract | Compounds of the formula:-<FORM:0562313/IV/1> are prepared by treating dibasic acid esters of the formula:-R1OOC.CH2.S.CH2.CH2.COOR2, where R1 and R2 are alkyl groups, with alkaline condensing agents such as alkali metals and their derivatives, e.g. sodium, sodamide, and sodium ethylate, to effect ring closure with elimination of an alcohol R2OH. In examples: (1) S-carbethoxyethyl-thioglycollic acid ethyl ester, obtained by treating S-carboxyethylthioglycollic acid with ethyl alcohol and HCl, is dissolved in benzene and heated with sodium. The mixture is cooled, acidified with H2SO4, and the benzene layer separated, washed, dried, the benzine evaporated, and distilled under reduced pressure to yield 2-carbethoxy-3-ketotetrahydrothiophene. The sodium may be replaced by sodamide or the solvent dispensed with and the ester treated with sodium and a little ethyl alcohol; (2) S-carbmethoxyethylthioglycollic acid methyl ester in analogous manner yields 2 - carbmethoxy - 3 - keto - tetrahydrothiophene; (3) b -chlorpropionic acid ethyl ester in ethyl alcohol is heated with thioglycollic acid in aqueous caustic soda, and the mixture cooled and acidified. The precipitated oil is extracted with ether, dried, the ether evaporated and the residue treated with benzene and heated with thionyl chloride. The product, obtained by distilling under reduced pressure, is S - carbethoxy - ethyl - thioglycollic acid chloride which is converted to the methyl ester with methanol. This ester is dissolved in benzene and treated with sodium to give 2-carbmethoxy-3-keto-tetrahydrothiophene; (4) S-carbethoxymethyl-thiolpropionic acid methyl ester, prepared as in (3) using b -chlorpropionic methyl ester and treating the acid chloride with ethanol, in similar manner yields 2-carbethoxy-3-keto-tetrahydrothiophene; (5) S-carbmethoxyethyl-thioglycollic acid chloride prepared from b -chlorpropionic methyl ester is treated with n-butanol to give the n-butyl ester which by the action of sodium gives the n-butyl ester of 2-carboxy-3-keto-tetrahydrothiophene; (6) the n-butyl ester of S-carboxyethyl-thioglycollic acid methyl ester, made from S-carbmethoxymethyl-thiolpropionic acid chloride and n-butanol, is reacted with sodium to yield 2-carbmethoxy-3-keto-tetrahydrothiophene; (7) S-carbmethoxymethyl-thiolpropionic acid isopropyl ester, made by reacting b -chlorpropionic isopropyl ester and thioglycollic acid, forming the acid chloride, and treating with methyl alcohol, is treated with sodium to form 2-carbmethoxy-2-keto-tetrahydrothiophene. |
| priorityDate | 1942-12-22-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
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Total number of triples: 51.