| 摘要 |
1530856 Preparing 1-aminoalkane-1,1-diphosphoric acids BENCKISER-KNAPSACK GmbH 23 May 1977 [9 June 1976] 21603/77 Heading C2P A compound having the general formula wherein R is a saturated aliphatic hydrocarbon radical of 1 to 12 C atoms which may be substituted by a diethoxyphosphinyl group is obtained by reacting a nitrile: RCN with phosphorous acid at 140-200‹ C. The nitrile and the phosphorous acid are suitably reacted in a molar ratio of about 1 : 2. In a modification a minor proportion by weight of the phosphorous acid is replaced by an equivalent amount of pyrophosphorous acid. The process may be carried out in the presence of a catalyst, e.g. a Lewis acid such as AlCl 3 , ZnCl 2 , AlBr 3 and SbCl 5 and may also be carried out in an aprotic solvent having a boiling point of above 150‹ C. The products may be converted to their alkali metal or alkaline earth metal salts by neutralizing an aqueous suspension of the acid with the corresponding metal hydroxide. The products are useful as chelating agents, e.g. in water treatment, in the treatment of textiles or in paper manufacture. |
