Chelating agents development

Lignox [Lignin oxidation] A pulp-bleaching process using hydrogen peroxide as the oxidant, and a chelating agent. Developed in Sweden in 1990 by Eka Nobel. See also Acetox. 

The first chelating agent developed as an antidote to a heavy metal poison was 2,3-dimereaptopropanol (dimercaprol, British Anti-Lewisite, BAL). Originally intended for use on victims of the arsenical vesicant poison gas Lewisite52, it has since proved efficacious in the treatment of antimony, gold and mercury poisoning as well as... 

The great stability of these ring systems was known, and possible biological implications of compounds having similar structures were postulated. As a result extensive research in macrocyclic chelating agents developed (13). 

Powerful new metal chelating agents developed in Chem. Eng. News (August 1st 1988) 21. 

Addition of secondary chelating agents, eg, polyols such as sorbitol or mannitol and the strongly chelating a-hydroxycarboxyhc acids such as citric or oxahc, prevents development of turbidity outside the pH range of 9—11 (115—117). 

Fluorinated phosphonates exhibit interesting properties as enzyme inhibitors, chelating agents or as fuel cell electrolytes [29] however, only few methods of preparation for these compounds are available. Burton et al. [30] developed several methods to prepare fluorinated phosphates which involve phosphonyl, and likely phosphoranyl radicals as chain carriers (Scheme 11). 

Develop bifunctional ligands which NCI, NIH have a high affinity for Pb(ll) and Bi(lll) systematic exploration of incorporating thiol donor groups into chelating agents... 

Bioavailable trace elements in soil correlate with plant uptake and concentrations in plants. Extractants for bioavailable trace elements include chelating agents, diluted inorganic acid, neutral salt solutions, and water (Table 7.2). The most popular extractant for bioavailable trace elements in arid and semi-arid soils is DTPA-TEA (triethanolamine), which was developed by Lindsay and Norvell (1969, 1978) to extract available Cu, Zn, Fe and Mn from neutral and calcareous soils. Use of this chelating agent, DTPA, is based on the fact that it has the most favorable combination of stability constants for simultaneous complexation of Cu, Fe, Mn and Zn... 

Amidocarbonylation converts aldehydes into amido-substituted amino acids, which have many important industrial applications ranging from pharmaceuticals to detergents and metal-chelating agents.588 Two catalyst systems have been developed, a cobalt-based system and, more recently a palladium-based system. In the cobalt system, alkenes can be used as the starting material, thus conducting alkene-hydroformylation, formation of hemi-amidal and carbonylation in one pot as... 

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