http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-1495271-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_5cc22c9470e3a0057b1261ce47c7f81b |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07D489-02 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07D489-02 |
| filingDate | 1974-04-10-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1977-12-14-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-1495271-A |
| titleOfInvention | Dehydrohalogenation of codeinone derivatives |
| abstract | 1495271 Dehydrohalogenation of halogensubstituted dihydrocodeinone dialkyl ketals MACFARLAN SMITH Ltd 24 March 1975 [10 April 1974] 15971/74 Heading C2C A 7-halo- or 1,7-dihalo-dihydrocodeinone dialkyl ketal of Formula I where R is C 1 -C 6 alkyl, X is hydrogen, chlorine or bromine and Y is chlorine or bromine, is dehydrohalogenated by the action of a base in the presence of a polar aprotic solvent; the product is a codeinone dialkyl ketal optionally substituted in the 1-position with Cl or Br. The base is suitably an alkali metal hydroxide, alkoxide, amide or hydride; the aprotic solvent is for example a dialkylsulphoxide, dialkyl formamide, dialkyl acetamide, alkyl phosphoramide, glycol ether, polyglycol ether or sulphone. The reaction may be carried out in the presence of up to 20% v/v water. The product codeinone ketal may be hydrolysed to codeinone (optionally substituted with Cl or Br in the 1-position) and this may be reduced to codeine. Preparation of starting materials of Formula I in which X = H and (a) Y=Br, R=n.propyl, (b) Y=Br, R= n.pentyl, and (c) Y = Cl and R = methyl, is described; they are obtained from dihydrothebaines. The compounds of Formula I in which X is hydrogen and Y is chlorine are claimed as novel. |
| priorityDate | 1974-04-10-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 39.