Complexes with iron compounds

Jiang S, Agoston GE, Chen T, Cabal M-P, Turns E (1995) BF3 Et20-promoted allylation reactions of allyl(cyclopentadienyl)iron(II) dicarbonyl complexes with carbonyl compounds. Organometallics 14 4697 -709... 

In the held, a 3-1 cartridge of 1 1 (by volume) quartz sand and iron filings removed >85 % of 1-1.5 mgL-1 of arsenic ( 30% organic arsenic) over four months from 16 000L of groundwater at the Vineland, New Jersey, United States, Superfund site. Cheng et al. (2005, 7666) speculated that MMA(V) formed stable bidentate complexes (Chapter 2) with iron compounds, whereas DMA(V) could not. 

Bis[iV,iV -di(2-pyridyl)-imidazol-2-ylidene]aurate(I) tetrafluoroborates, preparation, 2, 292-293 Bis[iV,iV -di(2-pyridyl-methyl)-imidazol-2-ylidene]aurate(I) tetrafluoroborates, preparation, 2, 292-293 Bis(diselenolate) complexes, dinuclear iron compounds, 6, 242 Bis(dithiolene) compounds, in tungsten carbonyl and isocyanide complexes, 5, 644 Bis(enolato) complexes, with bis-Cp Ti(IV), 4, 589 Bis(enones), in reductive cyclizations, 10, 502 Bis(ethanethiolato) complexes, with bis-Cp Ti(IV), 4, 601 Bis(ethene)iridium complexes, preparation, 7, 328-329 -Bis(fluorenyl)zirconocene dichlorides, preparation,... 

Cyclic diazo compounds are known to form mononuclear cr-complexes with iron carbonyl compounds, which further react to give more stable binuclear complexes containing an Fe-Fe bond <1976TCC105>. However, such complexes are rare in the case of cyclic four-membered diazo compounds. No new examples have been reported in the last decade. For more informations, CHEC-II(1996) should be consulted <1996CHEC-II(1B)911>. 

While the mercury compound shows localized N—Hg bonds, the TADB-system (which is isoelectronic with cyclopentadiene) forms a low-spin complex with iron. This was the first identified example of a sandwich-compounds of a boron-nitrogen ring. The complex is prepared by adding an etheric solution of TADBLi to a suspension of FeCl2 in tetra-hydrofuran. 

An important environmental issue is the fate of cyanide. HCN, if spilled, evaporates quite readily. That which does not evaporate is soon decomposed or rendered nonhazardous by complexing with iron in the soil, by biological oxidation or by degradation from photolysis129. Several methods for treatment and disposal of cyanide compounds are described in references 129 and 133. 

In an undivided electrolytic cell, the electro-Fenton process leads to the destruction of organics contained in wastewaters by simultaneous oxidation with OH formed at the anode surface from reaction (19.9) and in the medium from Fenton s reaction (19.12). Parallel slower reaction of pollutants with weaker oxidants such as H202, H02, S20g2-, and O3 formed from reactions (19.1), (19.4), (19.10), and (19.11), respectively, is also possible. In addition, final carboxylic acids can form complexes with iron ions that are difficult to be oxidized by OH. We will see the notable influence of the anode material (Pt or BDD) on the degradation of these compounds in further sections. 

The formulator needs to know the properties of each antioxidant. For example, most of the antioxidants are easily distilled by heat or steam. Propyl gallate will form strong purple complexes with iron. The preservative effects of antioxidants also can be enhanced by addition of metal chelating agents like citric acid. Furthermore, many crude feedstuffs of plant origin, including soybean meal, crude soybean oil, and lecithin, contain a variety of natural quinone-type compounds with beneficial antioxidant properties that do not require labeling. 

Phosphate is better used when supplied by food than when supplied by phosphate salts, such as potassium phosphate. The food phosphate occurs largely as phosphate esters and, with gradual hydrolysis, enters the body relatively slowly and is used efficiently in the metabolic processes. Phosphate supplied as inorganic phosphate is rapidly absorbed, with a tendency to be excreted in the urine rather than to be used by tissues (Schuette and Linkswilcr, 1962). The phosphate in bran occurs largely in the form of phytic acid (inositol hexaphosphate). The phosphate groups of fhis compound may be only partially hydrolyzed in the gut- Phytic acid tends to be excreted via the fecal route as a complex with iron or calcium. 

Dipyridyl and orthophenanthroline form particularly stable complexes with iron. The octahedral [Fe(phcn)3] + ion (Fig. 2C4) is blood-red but is oxidised to pale blue [Fe(phen)3] without any structural change. for the system = 1.14 V, making the compound, also known as ferroin, a most useful redox indicator for the oxidation of Fe + ion Fe +/Fe + = 0.77 V) by cerium(IV) ion (E Ce +/Ce + = 1.45 V). 

Dexrazoxane is the 5-( + )-isomer of razoxane. It is a potent intracellular chelating agent that is used for cardiopro-tection in patients receiving doxorubicin. - Dexrazoxane has two imide groups that open intracellularly to form a compound related to EDTA. This compound complexes with iron and interferes with free radical generation as.sociated with doxorubicin-iron complexes. 

A number of P(V) acid containing dendrimers have been synthesised. Examples include those starting from a hexachlorotriphosphazene core, e.g. 11 which could be complexed with iron or tungsten compounds, compounds up to seven generation possessing terminal P(S)(N-allyl2)Cl fragments which can be further... 

A class of organic compounds known as 1,10-phenanthrolines, or orthophenanthrolines, form stable complexes with iron(II) and certain other ions. The parent compound has a pair of nitrogen atoms located in such positions that each can form a covalent bond with the iron(II) ion. 

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