http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-796356-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_dd7138fe704652701d08ca1b568f33f3 |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07C291-08 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07C241-02 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C241-02 |
| filingDate | 1955-08-05-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1958-06-11-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-796356-A |
| titleOfInvention | Reduction of aromatic nitrogen compounds |
| abstract | A process for the reduction of a reducible aromatic nitrogen compound containing nitrogen as a nuclear substituent of a benzene nucleus at a higher stage of oxidation than the hydrazo stage, with a reducing sugar and caustic alkali, comprises carrying out the reduction in a reaction medium in which a naphthoquinoid reduction promoter has been incorporated. The reduction is preferably carried out in a medium containing a water-miscible organic solvent. The term naphthoquinoid reduction promoter includes all the reduction promoters specified in Specifications 701,128, 716,418, 730,748, 776,716 and 780,631, 780,632, which describe reductions using metal alcoholates. The process is particularly applicable to the reduction of aromatic nitrogen compounds containing labile halogen substituents. Specified solvents are monohydric alcohols containing not more than six carbon atoms. Specified reducing sugars are glycol aldehyde, glycerol aldehyde, erythrose, arabinose, xylose, fructose, invert sugar, galactose and dextrose. Specified reducible aromatic nitrogen compounds are nitrobenzene, 2- or 3- or 4-nitrochlorobenzene, 2- or 3- or 4-nitrotoluene, 2- or 4-nitroanisole, 2-or 4-nitrobenzoic acid, 2-nitrobenzene-sulphonic acid, 2 : 5-dimethyl-nitrobenzene, 2- or 4-nitrophenetole, 2 : 5-dichloronitrobenzene, 2 : 21- or 3 : 31-azoxytoluene, 2 : 21-azoxyanisole, 2 : 21 or 3 : 31-dichloro-azoxybenzene, 4 : 41-azoxydibenzoic acid, azobenzene, 2 : 21-azotoluene, 2 : 21-azoanisole and 2 : 21-dichloroazobenzene. In examples: (1) 2-chloronitrobenzene was reduced in aqueous medium with dextrine and sodium hydroxide in the presence of 2 : 3-dichloro-1 : 4-naphthoquinone to give a mixture of 2 : 21-dichloro-azoxy- and -azo-benzenes; (2) 2 : 21-dichloroazoxybenzene was reduced in methanol with dextrose and sodium hydroxide in the presence of 2 : 3-dichloro-1 : 4-naphthoquinone to give 2 : 21-dichlorohydrazobenzene and some 2-chloroaniline; (3) as in (2) azoxybenzene was reduced to hydrazobenzene; (4) as in (2) 2 : 21-dimethoxyazobenzene was reduced to 2 : 21-dimethoxyhydrazobenzene; (5) as in (2) 2 : 21-dichloroazoxybenzene was reduced to 2 : 21 - dichlorohydrazobenzene; (6) 2 - chloronitrobenzene was reacted with methanol and sodium hydroxide to give 2-methoxynitrobenzene; to the reaction mixture thus obtained were added further sodium hydroxide and methanol and 2 : 3 - dichloro - 1 : 4 - naphthoquinone and the mixture was reacted further to form 2 : 21-dimethoxyazobenzene and 2 : 21-dimethoxyazoxybenzene, dextrose being then added to complete the reduction to 2 : 21-dimethoxyhydrazobenzene which was rearranged with acid to give 3 : 3-dimethoxybenzidine hydrochloride. In Examples (1), (2) and (3) the process was also carried out in the absence of the naphthoquinoid reduction promoter for purposes of comparison. |
| isCitedBy | http://rdf.ncbi.nlm.nih.gov/pubchem/patent/CN-103044268-A |
| priorityDate | 1954-08-06-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 77.