New amino di:carboxylic-N,N-di:acetic acid deriv., useful as complexing agents - is prepd. from amino di:carboxylic acids, formaldehyde and hydrocyanic acid, or alkali metal cyanide, with amino di:carboxylic acid-N,N-di:acetonitrile as intermediate

摘要

New aminodicarboxylic acid-N,N-diacetic acids of formula (I) are prepd. by reacting aminodicarboxylic acids of formula XOOC-(CH2)n-CH-COOX (II), in water and/or an organic solvent, with 2-2.6 mols of HCHO and 2-2.3 mols of liq. HCN at 0-150 deg. C., or with 2-2.3 moles of alkali metal cyanide at 40-100 deg. C., and hydrolysing amide or CN gps. formed, in presence of an acid or a base. Aminodicarboxylic acid-N,N-diacetonitriles of formula XOOC- (CH2)n-CH (N(CH2CN)2 COOX (III), formed as intermediates, are also claimed. In the formulae, X = H, alkali metal, NH4 or ammonium gp. substd. with 1-4C alkyl or hydroxyalkyl; and n = 1-4. USE/ADVANTAGE - (I) are prepd. in high purity and good yield, from easily available cpds., by a simple, efficient process applicable on the large scale and giving almost no loading with inorganic salt. (I) can be used in alkaline media, overcoming corrosion problems. (I) are complex-formers, esp. for alkaline earth and heavy metal ions, and can be used in washing compsns. and solns. to control the content of free heavy metal ions, as bleach stabilisers, e.g. for NaBO3, as builders, and in bleaching textiles, cellulose or paper pulp, to prevent destruction of the bleach system, enzymes, optical bleaches and perfumes by heavy metal ions.