| 摘要 |
Azo compounds of the general formula <FORM:0672106/IV (b)/1> (wherein R1 represents methyl or ethyl and X represents a carboxyl group, free or esterified with a saturated monohydric aliphatic alcohol of not more than three carbon atoms, or especially a nitrile group) are manufactured by the action of a hypochlorite in dilute alkaline solution on a compound of the formula <FORM:0672106/IV (b)/2> at a temperature below 15 DEG C. Suitable hypochlorites are alkali and alkaline-earth metal hypochlorites (which should be used in a concentration not exceeding 7 per cent, e.g. 3-5 per cent, and a solution of which in dilute alkali may be prepared in situ by passing chlorine into aqueous alkali or alkaline-earth metal hydroxide solution), or alkyl hypochlorites (which may be prepared by mixing a metal hypochlorite solution with a lower alcohol, especially a tertiary alcohol, in which the amine to be oxidized may be previously dissolved). The products are useful as blowing agents for preparing foamed rubber, and as polymerization catalysts. Examples describe the oxidation of: (1), (2) and (5) a -aminoisobutyronitrile with sodium hypochlorite; (3) and (4) the same compound with calcium hypochlorite; (6) a -aminoisobutyric acid with sodium hypochlorite; (7) a -amino-a -methylbutyronitrile with calcium hypochlorite; (8) ethyl or propyl a -aminoisobutyrate or ethyl a -amino-a -methylbutyrate with sodium hypochlorite; (9), (10) and (12) a -aminoisobutyronitrile with tert.-butyl hypochlorite; (11) the same compound with tert.-amyl hypochlorite. a - Aminoisobutyronitrile and a - amino - a - methylbutyronitrile are obtainable from acetone and methyl ethyl ketone respectively by formation of the cyanhydrins and reaction of these with ammonia. Ethyl and isopropyl a -aminoisobutyrates and ethyl a -amino-a -methylbutyrate are obtainable by passing hydrogen chloride into a mixture of a -aminoisobutyronitrile or a -amino-a -methylbutyronitrile with chloroform and anhydrous ethanol, or, in the former case, isopropanol. |
