| 摘要 |
1,270,863. Bipyridylium salts. IMPERIAL CHEMICAL INDUSTRIES Ltd. 28 July, 1970 [20 Aug., 1969; 4 March, 1970], Nos. 41516/69 and 10421/70. Heading C2C. 1,1<SP>1 </SP>- Disubstituted - 4,41 - bipyridylium salts, in which each of the substituent groups contains up to 10 carbon atoms, are prepared by reacting the corresponding N-substituted pyridinium salt under basic conditions with anions containing the structure and subsequently oxidizing the resulting interaction product to give 1,1<SP>1</SP>-disubstituted pyridylium salts. The process is preferably carried out in a solvent for the N-substituted pyridinium salt. The preferred substituents in the N-substituted pyridinium salts used as starting materials are alkyl and carbamidoalkyl groups and the pyridine nucleus may also carry substituents on the carbon atoms. The intermediate product a 1,1<SP>1</SP>-disubstituted-dihydro- 4,4<SP>1</SP>-bipyridyl which may be oxidized to the corresponding bipyridylium salt by treatment, for example, with ceric sulphate (in dilute sulphuric acid), metal salts, inorganic oxyacid anhydrides, air preferably in conjunction with water and/or carbon dioxide and/or an acid, benzoquinone, chloranil or anthraquinone. The 1,1<SP>1</SP> - disubstituted - 4,41 - bipyridylium cations may be separated from the ions of the phosphorus compound in the reaction mixture by treatment with 4,4<SP>1</SP>-diaminostilbene-2,2<SP>1</SP>-disulphonic acid (amsonic acid). The salt is precipitated as the amsonate which may be separated and reacted with another acid, e.g. hydrochloric, phosphoric or acetic acid. Alternatively the bipyridylium cations may be separated from the ions of the phosphorus compound by treating the reaction mixture with a cation-exchange resin. The compounds yielding the phosphorus containing ions may be prepared in situ. |
