Hypochlorite oxidation equivalents

On prolonged storage, the hypochlorite ions disproportionate gradually into chloride and chlorate. Hypochlorite solutions may also be decomposed to chloride and oxygen in the presence of heavy metal ions. When hypochlorite is reduced to chloride two oxidation equivalents are consumed. For example, 1 M hypochlorite solution contains 2 x 35.5 = 71 g/liter of active chlorine. 

Ferrate is a tetrahedral ion, where all the Fe-O bonds are equivalent and covalent. It can be prepared either chemically or electrochemically. In the chemical synthesis, a strong alkaline solution of hypochlorite oxidizes Fe(III) ... 

Cl, from which hypochlorite is generated, are sufficient to oxidize AuSTm to gold(in). The gold(lll) species are not immunogenic but hkely react with proteins to generate antigenic species and may carry oxidizing equivalents from the site of the oxidative burst to other cells or macromolecules. 

The Lewis acid-catalysed orientation reversal in the reaction between substituted cyclohexa-1,3-dienes and 2,6-dimethyl-l,4-benzoquinone ° has been employed in an interesting synthesis of quassin (218). ° Thus, reaction at room temperature of the diene (215) with the above quinone in the presence of an equivalent quantity of Bp3,OEt2 gave the adduct (216) which was converted by several subsequent steps into (218). In the absence of the catalyst the alternative adduct (217) was obtained. Periodic acid oxidation of substituted o-cresols ° and of 2-methoxyphenols in methanol solution affords intermediate o-quinol methyl ethers or o-quinone dimethyl ketals which dimerize to give dienediones with structures related to those of (216) and (217). Another report concerns the formation of a Diels-Alder dimer upon hypochlorite oxidation of 2,2 -methylenebis(4-methyl-6-t-butyl)phenol. ... 

High yields of NaOCl are obtained electrolyticaHy by oxidation of CT at dimensionally stable anodes (219). Sodium hypochlorite is prepared using small diaphragmless or membrane cells, with a capacity of 1—150 kg/d of equivalent CI2, which produce a dilute hypochlorite solution of 1—3 and 5—6 g/L from seawater and brine, respectively (see Chemicals from brine). They are employed in sewage and wastewater treatment and in commercial laundries, large swimming pools, and aboard ships. 

In another procedure, oxidation is carried out in the presence of chloride ions and ruthenium dioxide [31]. Chlorine is generated at the anode and this oxidises ruthenium to the tetroxide level. The reaction medium is aqueous sodium chloride with an inert solvent for the alkanol. Ruthenium tetroxide dissolves in the organic layer and effects oxidation of the alkanol. An undivided cell is used so that the chlorine generated at the anode reacts with hydroxide generated at the cathode to form hypochlorite. Thus this electrochemical process is equivalent to the oxidation of alkanols by ruthenium dioxide and a stoichiometric amount of sodium hypochlorite. Secondary alcohols are oxidised to ketones in excellent yields. 1,4- and 1,5-Diols with at least one primary alcohol function, are oxidised to lactones while... 

Dichlorination was also observed when two molar equivalents of NCS or /-butyl hypochlorite reacted with 1-hydroxypyrazoles and their 2-oxides. One equivalent of NCS gave only the 4-monochloro derivative in high yield (80JOC76). When there was already a 4-substituent present, as with 3,4,5-trisubstituted pyrazole 2-oxides or 1-hydroxy-3,4,5-trisubsti-tuted pyrazole 2-oxides, the reaction products were 4-chloro-4// derivatives (77JOC3721). With 2 mol of /-butyl hypochlorite, 3,5-diphenylpyra-zole gave the unstable 1,4-dichloro derivative, which rearranged to form... 

Of the myriad of modified starch systems tested, ranging from simple enzymically dextrinized starches to covalently attached amino acids and peptides onto dextrinized and/or oxidized (hypochlorite or periodate) corn starch bases, two polymers were selected as holding promise. The first system was a low dextrose equivalent (DE 5.7) enzyme-modified corn starch. The second starch-based polymer developed was a periodate-oxidized, amylase-dextrinized, covalently-attached phenylalanine glycoamine. 

Fluoro-2,2-dimtroethylarrune is oxidized by m-chloroperoxybenzoic acid to the corresponding hydroxylamine, which, on further oxidation by a second equivalent of the peroxyacid or bromine, gives an oxime [55] (equation 77) Oxidation of pentafluoroaniline by sodium hypochlorite under phase-transfer conditions leads to perfluoroazobenzene as the main product 186] (equation 78)... 

Oxidation of alcohols to carbonyl compounds using the stable nitroxyl radical TEMPO (41) as catalyst is a well-known preparative method [42, 43], Hypochlorite or peracetic acid is usually used as the final oxidizing agent and ca. 1 mol% of the catalyst 41 is used. In 1996 Rychnovsky et al. reported the synthesis of the chiral, binaphthyl-derived TEMPO analog 42 [44]. Table 12.1 lists the results obtained with 0.5-1 mol% of catalyst 42 [44], In these oxidation reactions 0.6-0.7 equivalents of sodium hypochlorite were used as the final oxidizing agent (plus 0.1 equiv. potassium bromide) in a two-phase system containing substrate and catalyst 42 in dichloromethane at 0 °C. As shown, the best selectivity factors (> 5) were observed for 1-phenylethanol and its derivatives as substrates. 

To make the DERA-catalyzed process commercially attractive, improvements were required in catalyst load, reaction time, and volumetric productivity. We undertook an enzyme discovery program, using a combination of activity- and sequence-based screening, and discovered 15 DERAs that are active in the previously mentioned process. Several of these enzymes had improved catalyst load relative to the benchmark DERA from E. coli. In the first step of our process, our new DERA enzymes catalyze the enantioselective tandem aldol reaction of two equivalents of acetaldehyde with one equivalent of chloroacetaldehyde (Scheme 20.6). Thus, in 1 step a 6-carbon lactol with two stereogenic centers is formed from achiral 2-carbon starting materials. In the second step, the lactol is oxidized to the corresponding lactone 7 with sodium hypochlorite in acetic acid, which is crystallized to an exceptionally high level of purity (99.9% ee, 99.8% de). 

It is not the same as calcium hypochlorite, which contains over 99 percent, available chlorine. (The term available chlorine refers to the oxidizing power of a bleach equivalent to that of free chlorine, as determined by the standard acidic-KJ-thiosulfate titration.)... 

Occasionally, the hypochlorites are used as the chlorinating-oxidizing agent. To determine the equivalent masses of the hypochlorites, they must be made to interact with electrons. On the basis of one electron mole. 

In each of the previous reactions, the manganese atom is oxidized from 2+ to 4+, involving 2 electron moles. Thus, the equivalent masses are manganese Mn/2 = 27.45, chlorine CI2/2 = 35.5, potassium permanganate = KMn04/2 = 52.67, ozone = O3/2 = 8, and oxygen = O2/2 = 8. The equivalent masses of sodium hypochlorite and calcium hypochlorite are the same as those in the case of the ferrous, which are 37.25 and 35.78, respectively. 

---