2,2',2''-Nitrilotriacetonitrile

Last updated
2,2',2''-Nitrilotriacetonitrile
Nitrilotriacetonitril Strukturformel.svg
Names
Preferred IUPAC name
2,2′,2′′-Nitrilotriacetonitrile
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.028.004 OOjs UI icon edit-ltr-progressive.svg
PubChem CID
UNII
  • InChI=1S/C6H6N4/c7-1-4-10(5-2-8)6-3-9/h4-6H2
    Key: LJAIDEYQVIJERM-UHFFFAOYSA-N
  • C(C#N)N(CC#N)CC#N
Properties
C6H6N4
Molar mass 134.142 g·mol−1
Structure [1]
Pnma
orthorhombic
a = 7.1085, b = 9.9320, c = 9.3869
Hazards
GHS labelling:
GHS-pictogram-skull.svg GHS-pictogram-exclam.svg GHS-pictogram-silhouette.svg
Danger
H301, H302, H312, H315, H319, H335, H373
P260, P261, P264, P270, P271, P280, P301+P310, P301+P312, P302+P352, P304+P340, P305+P351+P338, P312, P314, P321, P322, P330, P332+P313, P337+P313, P362, P363, P403+P233, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Nitrilotriacetonitrile (NTAN) is a precursor for nitrilotriacetic acid (NTA, a biodegradable complexing agent and building block for detergents), for tris(2-aminoethyl)amine (a tripodal tetradentate chelating agent known under the abbreviation tren) and for the epoxy resin crosslinker aminoethylpiperazine.

Contents

Production

The synthesis of nitrilotriacetonitrile is based on the basic building blocks ammonia, formaldehyde and hydrogen cyanide, which are reacted (via the triple cyanomethylation of the ammonia) in acidic aqueous medium in discontinuous or continuous processes. [2] [3]

Synthesis of nitrilotriacetonitrile NTAN Synthese von Nitrilotriacetonitril.svg
Synthesis of nitrilotriacetonitrile NTAN

Ammonia is introduced as a gas, in form of hexamethylenetetramine [4] or as ammonium sulfate together with formaldehyde as aqueous solution (usually 37% by weight) at pH values <2 and treated with aqueous prussic acid solution or liquid hydrogen cyanide at temperatures around 100 °C. Prussic acid is used directly from the Andrussow process or the BMA process of Evonik Degussa [5] without pre-purification if necessary. When the mother liquors are returned, yields of more than 90% are achieved.

Problematic, particularly in the case of a continuous process, is the tendency of NTAN to precipitate at temperatures below 90 °C which can lead to clogging of tube reactors and conduits and thermal runaway of the reaction. [6]

Properties

Nitrilotriacetonitrile is a colorless and odorless solid which dissolves hardly in water but dissolves well in nitromethane and acetone. [7]

Use

Nitrilotriacetonitrile can be homopolymerized or copolymerized with iminodiacetonitrile in the melt in the presence of basic catalysts such as sodium methoxide to form dark-colored solid polymers which can be carbonized to form nitrogen-containing and electrically conductive polymers at temperatures above 1000 °C. [8] The products obtained have not found application as conductive polymers.

The hydrogenation of NTAN first converts a cyano group into an imino group which attacks a cyano group (which are adjacent and sterically suitable for forming a six-membered ring) rather than being further hydrogenated to the primary amino group. The end product of the catalytic hydrogenation of nitrilotriacetonitrile is therefore 1-(2-aminoethyl)piperazine.

Synthesis of aminoethylpiperazine by hydrogenation of NTAN Synthese von Aminoethylpiperazin aus NTAN.svg
Synthesis of aminoethylpiperazine by hydrogenation of NTAN

If the catalytic hydrogenation of NTAN is carried out with e. g. Raney nickel in the presence of a large excess of ammonia, it gives tris(2-aminoethyl)amine. [9]

Synthesis of tris (2-aminoethyl) amine(tren) Synthese von tren.svg
Synthesis of tris (2-aminoethyl) amine(tren)

Tris(2-aminoethyl)amine is used as a tetrazident complexing agent (abbreviated as "tren"), which forms stable chelates, particularly with divalent and trivalent transition metal ions. [10]

Nitrilotriacetonitrile reacts with methanal at pH 9.5 to give 2,2-dihydroxymethyl-nitrilotriacetonitrile, which is hydrolyzed with sodium hydroxide solution at 100 °C to give the trisodium salt of 2-hydroxymethylserine-N,N-diacetic acid, from which the free acid can be obtained by acidification in 51% yield. [11]

Synthesis of 2-hydroxymethylserine-N, N-diacetic acid trisodium salt from NTAN Synthese von 2-Hydroxymethylserin-N,N-diessigsaure-trinatriumsalz.svg
Synthesis of 2-hydroxymethylserine-N, N-diacetic acid trisodium salt from NTAN

The compound is suitable as a complexing agent for heavy metal ions or alkaline earth metal ions, as a stabilizer for bleaching agents (e.g. for sodium perborate, in solid detergent preparations) and as a builder in detergents for inhibiting the formation of incrustations in textiles during laundering.

The hydrolysis of nitrilotriacetonitrile with water in concentrated sulfuric acid yields under gentle conditions practically quantitatively nitrilotriacetamide, which has been investigated as a neutral tetradentate ligand for metal complexation. [12] At elevated temperature, 3,5-dioxopiperazine-1-acetamide is formed by ring closure, which can be quantitatively converted into the nitrilotriacetamide after neutralization and heating with excess aqueous ammonia. [13] [14]

Synthesis of nitrilotracetamide (and 3,5-dioxopiperazine-1-acetamide) Synthese von Nitrilotracetamid.svg
Synthesis of nitrilotracetamide (and 3,5-dioxopiperazine-1-acetamide)

Nitrilotriacetonitrile serves mainly as a raw material for the production of the biodegradable, but carcinogen suspected complexing agent nitrilotriacetic acid by acid or base-catalyzed [15] [2] hydrolysis of the cyano groups.

Alkaline hydrolysis of NTAN to NTA trisodium salt Hydrolyse von NTAN zu NTA-trinatriumsalz.svg
Alkaline hydrolysis of NTAN to NTA trisodium salt

Undesirable residual contents of cyanide ions in the hydrolyzate can be removed by post-treatment with oxidizing agents such as sodium hypochlorite at pH 8. [16]

Related Research Articles

<span class="mw-page-title-main">Cyanide</span> Any molecule with a cyano group (–C≡N)

In chemistry, a cyanide is a chemical compound that contains a C≡N functional group. This group, known as the cyano group, consists of a carbon atom triple-bonded to a nitrogen atom.

<span class="mw-page-title-main">Hydroxide</span> Chemical compound

Hydroxide is a diatomic anion with chemical formula OH. It consists of an oxygen and hydrogen atom held together by a single covalent bond, and carries a negative electric charge. It is an important but usually minor constituent of water. It functions as a base, a ligand, a nucleophile, and a catalyst. The hydroxide ion forms salts, some of which dissociate in aqueous solution, liberating solvated hydroxide ions. Sodium hydroxide is a multi-million-ton per annum commodity chemical. The corresponding electrically neutral compound HO is the hydroxyl radical. The corresponding covalently bound group –OH of atoms is the hydroxy group. Both the hydroxide ion and hydroxy group are nucleophiles and can act as catalysts in organic chemistry.

Hydrolysis is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile.

Hydrogen cyanide is a chemical compound with the formula HCN and structural formula H−C≡N. It is a colorless, extremely poisonous, and flammable liquid that boils slightly above room temperature, at 25.6 °C (78.1 °F). HCN is produced on an industrial scale and is a highly valued precursor to many chemical compounds ranging from polymers to pharmaceuticals. Large-scale applications are for the production of potassium cyanide and adiponitrile, used in mining and plastics, respectively. It is more toxic than solid cyanide compounds due to its volatile nature.

<span class="mw-page-title-main">Ethylenediaminetetraacetic acid</span> Chemical compound

Ethylenediaminetetraacetic acid (EDTA), also called edetic acid after its own abbreviation, is an aminopolycarboxylic acid with the formula [CH2N(CH2CO2H)2]2. This white, water-insoluble solid is widely used to bind to iron (Fe2+/Fe3+) and calcium ions (Ca2+), forming water-soluble complexes even at neutral pH. It is thus used to dissolve Fe- and Ca-containing scale as well as to deliver iron ions under conditions where its oxides are insoluble. EDTA is available as several salts, notably disodium EDTA, sodium calcium edetate, and tetrasodium EDTA, but these all function similarly.

In organic chemistry, a nitrile is any organic compound that has a −C≡N functional group. The name of the compound is composed of a base, which includes the carbon of the −C≡N, suffixed with "nitrile", so for example CH3CH2C≡N is called "propionitrile". The prefix cyano- is used interchangeably with the term nitrile in industrial literature. Nitriles are found in many useful compounds, including methyl cyanoacrylate, used in super glue, and nitrile rubber, a nitrile-containing polymer used in latex-free laboratory and medical gloves. Nitrile rubber is also widely used as automotive and other seals since it is resistant to fuels and oils. Organic compounds containing multiple nitrile groups are known as cyanocarbons.

Hydrometallurgy is a technique within the field of extractive metallurgy, the obtaining of metals from their ores. Hydrometallurgy involve the use of aqueous solutions for the recovery of metals from ores, concentrates, and recycled or residual materials. Processing techniques that complement hydrometallurgy are pyrometallurgy, vapour metallurgy, and molten salt electrometallurgy. Hydrometallurgy is typically divided into three general areas:

<span class="mw-page-title-main">Liquid–liquid extraction</span> Method to separate compounds or metal complexes

Liquid–liquid extraction, also known as solvent extraction and partitioning, is a method to separate compounds or metal complexes, based on their relative solubilities in two different immiscible liquids, usually water (polar) and an organic solvent (non-polar). There is a net transfer of one or more species from one liquid into another liquid phase, generally from aqueous to organic. The transfer is driven by chemical potential, i.e. once the transfer is complete, the overall system of chemical components that make up the solutes and the solvents are in a more stable configuration. The solvent that is enriched in solute(s) is called extract. The feed solution that is depleted in solute(s) is called the raffinate. Liquid-liquid extraction is a basic technique in chemical laboratories, where it is performed using a variety of apparatus, from separatory funnels to countercurrent distribution equipment called as mixer settlers. This type of process is commonly performed after a chemical reaction as part of the work-up, often including an acidic work-up.

Ethylenediamine (abbreviated as en when a ligand) is the organic compound with the formula C2H4(NH2)2. This colorless liquid with an ammonia-like odor is a basic amine. It is a widely used building block in chemical synthesis, with approximately 500,000 tonnes produced in 1998. Ethylenediamine is the first member of the so-called polyethylene amines.

<span class="mw-page-title-main">Nitrilotriacetic acid</span> Chemical compound

Nitrilotriacetic acid (NTA) is the aminopolycarboxylic acid with the formula N(CH2CO2H)3. It is a colourless solid. Its conjugate base nitrilotriacetate is used as a chelating agent for Ca2+, Co2+, Cu2+, and Fe3+.

<span class="mw-page-title-main">Sodium cyanoborohydride</span> Chemical compound

Sodium cyanoborohydride is a chemical compound with the formula Na[BH3(CN)]. It is a colourless salt used in organic synthesis for chemical reduction including that of imines and carbonyls. Sodium cyanoborohydride is a milder reductant than other conventional reducing agents.

<span class="mw-page-title-main">Tris(2-aminoethyl)amine</span> Chemical compound

Tris(2-aminoethyl)amine is the organic compound with the formula N(CH2CH2NH2)3. This colourless liquid is soluble in water and is highly basic, consisting of a tertiary amine center and three pendant primary amine groups. Tris(2-aminoethyl)amine is commonly abbreviated as tren or TREN. It is used a crosslinking agent in the synthesis of polyimine networks and a tripodal ligand in coordination chemistry.

<span class="mw-page-title-main">Iminodiacetic acid</span> Chemical compound

Iminodiacetic acid is the organic compound with the formula HN(CH2CO2H)2, often abbreviated to IDA. A white solid, the compound is a dicarboxylic acid amine (the nitrogen atom forms a secondary amino group, not an imino group as the name suggests). The iminodiacetate dianion is a tridentate ligand, forming metal complexes by forming two, fused, five membered chelate rings. The proton on the nitrogen atom can be replaced by a carbon atom of a polymer to create an ion-exchange resin, such as chelex 100. Complexes of IDA and EDTA were introduced in the early 1950's by Schwarzenbach.

<span class="mw-page-title-main">Ammonium cyanide</span> Chemical compound

Ammonium cyanide is an unstable inorganic compound with the formula NH4CN.

<span class="mw-page-title-main">2-Mercaptopyridine</span> Chemical compound

2-Mercaptopyridine is an organosulfur compound with the formula HSC5H4N. This yellow crystalline solid is a derivative of pyridine. The compound and its derivatives serve primarily as acylating agents. A few of 2-mercaptopyridine’s other uses include serving as a protecting group for amines and imides as well as forming a selective reducing agent. 2-Mercaptopyridine oxidizes to 2,2’-dipyridyl disulfide.

Glycolonitrile, also called hydroxyacetonitrile or formaldehyde cyanohydrin, is the organic compound with the formula HOCH2CN. It is the simplest cyanohydrin and it is derived from formaldehyde. It is a colourless liquid that dissolves in water and ether. Because glycolonitrile decomposes readily into formaldehyde and hydrogen cyanide, it is listed as an extremely hazardous substance. In January 2019, astronomers reported the detection of glycolonitrile, another possible building block of life among other such molecules, in outer space.

<span class="mw-page-title-main">2-Methyleneglutaronitrile</span> Chemical compound

2-Methylene glutaronitrile is a dimerization product of acrylonitrile and a starting material for di- and triamines, for the biocide 2-bromo-2-(bromomethyl)pentanedinitrile and for heterocycles, such as 3-cyanopyridine.

<span class="mw-page-title-main">Tetrasodium iminodisuccinate</span> Chemical compound

Tetrasodium iminodisuccinate is a sodium salt of iminodisuccinic acid, also referred to as N-(1,2-dicarboxyethyl)aspartic acid.

<i>N</i>-(2-Carboxyethyl)iminodiacetic acid Chemical compound

N-(2-Carboxyethyl)iminodiacetic acid or β-ADA(β-alanine diacetate) is an organic compound with the formula HO2CCH2CH2N(CH2CO2H)2. It is a white solid. The compound is classified as an aminocarboxylic acid, formally a derivative of glycine.

<span class="mw-page-title-main">Trisodium dicarboxymethyl alaninate</span> Chemical compound

Trisodium N-(1-carboxylatoethyl)iminodiacetate, methylglycinediacetic acid trisodium salt (MGDA-Na3) or trisodium α-DL-alanine diacetate (α-ADA), is the trisodium anion of N-(1-carboxyethyl)iminodiacetic acid and a tetradentate complexing agent. It forms stable 1:1 chelate complexes with cations having a charge number of at least +2, e.g. the "hard water forming" cations Ca2+ or Mg2+. α-ADA is distinguished from the isomeric β-alaninediacetic acid by better biodegradability and therefore improved environmental compatibility.

References

  1. CSD Entry: CIRWOR 2,2',2-Nitrilotriacetonitrile
  2. 1 2 US 3337607,J.C. Wollensak,"Process for preparation of an amine nitrile",published 1967-08-22, assigned to Ethyl Corp.
  3. US 3840581,H. Neumaier, W. Vogt, K. Sennewald, R. Schuller, G. Lenz,"Process for the manufacture of nitrilotriacetonitrile",published 1974-10-08, assigned to Knapsack AG
  4. US 3061628,J.J. Singer Jr., M. Weisberg,"Process and preparation of amino nitriles and acetic acids",published 1962-10-30, assigned to Hampshire Chemical Corp.
  5. EP 0102343,C.Y. Shen,"Process for producing nitrilotriacetonitrile",published 1986-02-26, assigned to Monsanto Co.
  6. E. Fiedler (2016), "Emergency Runaway Reaction – What Precedes? What Follows?", Chem. Engineer. Transactions (CET), vol. 48, pp. 361–366, doi:10.3303/CET1648061, ISBN   978-88-95608-39-6
  7. "Product Stewardship Summary, Chelates: NTAN" (PDF). akzonobel.com. Akzo Nobel Functional Chemicals. Archived from the original (PDF; 45.7 KB) on 2013-06-02. Retrieved 2017-03-20.
  8. US 3578643,L.L. Wood, R.A. Hamilton,"New polymers from nitrilotriacetonitrile and iminodiacetonitrile",published 1971-05-11, assigned to W.R. Grace & Co.
  9. US 3565957,S.B. Mirviss, D.J. Martin, E.D. Weil,"Hydrogenation of nitrilotriacetonitrile",published 1971-02-23, assigned to Stauffer Chemical Co.
  10. G. Anderegg; V. Gramlich (1994), "1:1 Metal Complexes of Bivalent Cobalt, Nickel, Copper, Zink, and Cadmium with the Tripodal Ligand tris[2-(dimethylamino)ethyl]amine: Their stabilities and the X-ray crystal structure of its copper(II) complex sulfate", Helv. Chim. Acta , vol. 77, no. 3, pp. 685–690, doi:10.1002/hlca.19940770312
  11. EP 0396999,A. Oftring, S. Birnbach, R. Bauer, C. Gousetis, W. Trieselt,"2-Methyl- und 2-Hydroxymethyl-serin-N,N-diessigsäure und ihre Derivate",published 1990-11-14, assigned to BASF AG
  12. D.A. Smith; S. Sucheck; S. Cramer; D. Baker (1995), "Nitrilotriacetamide: Synthesis in concentrated sulfuric acid and stability in water", Synth. Commun., vol. 25, no. 24, pp. 4123–4132, doi:10.1080/00397919508011491
  13. GB 1170399,"A process for preparing 3,5-dioxo-1-piperazineacetamide and nitrilotriacetic acid triamide",published 1969-11-12, assigned to W.R. Grace & Co.
  14. D.A. Smith; S. Cramer; S. Sucheck; E. Skrzypzak-Jankun (1992), "Facile synthesis of substituted nitrilotriacetamides", Tetrahedron Lett. , vol. 33, no. 50, pp. 7765–7768, doi:10.1016/0040-4039(93)88040-P
  15. US 4547589,C.Y. Shen,"Hydrolysis of nitrilotriacetonitrile",published 1985-10-15, assigned to Monsanto Co.
  16. US 8362298,O.M. Falana, A. Hikem, S.R. Kakadjian, F. Zamora,"Hydrolyzed nitrilotriacetonitrile compositions, nitrilotriacetonitrile hydrolysis formulations and methods for making and using same",published 2013-01-29, assigned to Clearwater International, LLC