Patent GB-743126-A (GB)
Title: Hydroxy-aromatic alkylene polyamino polycarboxylic acids and derivatives thereof
Inventor: BERSWORTH FREDERICK CHARLES
IPC: A01N37/44
Filed: 1952-09-26
Abstract: The invention comprises compounds conforming to the following general formula: <FORM:0743126/IV(a)/1> wherein Alkylene is -CH2.CH2-, -CH2.CH2.CH2- or -CH(CH3).CH2-; n is 1, 2, 3, 4 or 5; X is hydrogen, hydroxyl, halogen, alkyl or alkoxyl and A is -CH2.COOM or -CH2.CH2COOM where M is hydrogen, alkali metal, ammonium or a substituted-ammonium group.  In examples: (I) Di-(o-hydroxy-phenyl) ethylene diamine diacetic acid is obtained by treating o-nitrosophenol in alcohol solution with excess cupric or nickelous hydroxide, converting the complex formed to di-(o-nitrosophenyl) ethylene diamine by reacting the complex with aqueous alcoholic ethylene diamine and passing hydrogen sulphide through the product to precipitate copper or nickel, reducing the product with hydrogen in the presence of a platinum or nickel catalyst and recovering di-(amino-o-phenyl)ethylene diamine as dihydrochloride, diazotizing the latter in aqueous solution with sodium nitrite and hydrochloric acid and allowing the product to hydrolyse to N,N1, di-(o-hydroxyphenyl) ethylene diamine, treating the latter with sodium cyanide, formaldehyde and sufficient caustic soda to give a pH of about 10 neutralizing the reaction solution with hydrochloric acid and allowing the desired product to crystallize.  The product is a chelating agent for all divalent heavy metals forming chelates which are soluble in water and has bactericidal and fungicidal properties. The tetrachloroderivative is prepared by passing chlorine through an aqueous solution of the dialkali metal salt and acidifying and crystallizing.  On further chlorination of the tetrachloro salt a compound having four chlorine substituents in each phenyl nucleus is formed.  Treatment of the aqueous solution with iodine or bromine in place of chlorine yields compounds containing from 2 to 4 bromine or iodine atoms in each ring.  The fully chlorinated compound is a bactericide and fungicide and its copper chelate is destructive to lower forms of plant life such as algae and fungi and may be used to impregnate wood or in natural waters to inhibit the growth of algae. The latter compound may also be prepared by heating N,N1-di-(penta-chlorophenyl) ethylenediamine (prepared, for example, by condensing hexachlorobenzene with ethylene diamine) with cupric hydroxide and caustic soda under pressure, recovering the copper complex, suspending the latter in water and treating with hydrogen sulphide to precipitate copper sulphide, preferably in the presence of alcohol, filtering off copper sulphide after adding more alcohol to dissolve the desired intermediate, evaporating the alcohol and water and after dissolving the residue in tertiary butyl alcohol boiling the solution with sodium cyanide and formaldehyde whilst withdrawing ammonia.  The alkali metal salt may be recovered by evaporation of the solution or the free acid precipitated by acidification; (II) N,N1-di-(2-hydroxy-4-methyl-6-methoxy phenyl)ethylene diamine diacetic acid is produced by heating 2-hydroxy-4-methyl-6-methoxy) phenylamine dissolved in pyridine with ethylene dichloride under pressure to form N,N1 - (2 - hydroxy - 4 - methyl - 6 - methoxy-phenyl) ethylene diamine, refluxing the latter with a cupric compound to form a copper complex, treating the complex with hydrogen sulphide to obtain N,N1-(2-hydroxy-4-methyl-6-methoxyphenyl) ethylene diamine, converting the latter to the corresponding diacetic acid salt by the process described above and obtaining the desired product by acidification.  On chlorination of the latter acid or the salt two atoms of chlorine may be introduced into each phenyl group. Acidification of the chlorinated salt yields the free acid which may be neutralized to yield the alkali metal salt.  The product is a bactericidal and fungicidal agent and forms chelates with most divalent metals.  Analogous compounds which are derivatives of propylene diamine, trimethylene diamine, and polyalkylene polyamines of the type H2N-(Alkylene-NH)n-Alkylene-NH2 in which alkylene is ethylene, propylene or trimethylene and n is 1, 2, 3 or 4 may be prepared by following the procedure of example (I) but using propylene diamine, trimethylene diamine or the desired polyalkylene polyamine in place of ethylene diamine and in molar equivalent proportions.  The products in general are stated to form chelate compounds with the transition elements and nickel, cobalt and iron specifically.  Formul  are proposed for chelate compounds containing copper and iron derived from compounds of the given general formula in which A=CH2CH2-, n=1 and A=CH2COOH.