Oxidants NaOCl

Asymmetric synthesis of Ar(CH2) S CHCl2.1 Oxidation (NaOCl) of arene-thioacetates, Ar(CH2)nSCH2COOR, complexed with p-cycloodextrin results in optically active a,oi-dichlorosulfoxides in 4-54% ee in 70-83% chemical yield. The highest optical yield is obtained in the oxidation of C6H5SCH2COOBu. 

Oxadiazole-2-oxides (furoxans) are generated by oxidative cychzation of the dioximes of 1,2-dicarbonyl compounds. As oxidants, NaOCl, Pb(OAc)4, or N2O4 have proved useful electrochemical oxidation is also possible [472]. 

A 25.00-mL sample of a liquid bleach was diluted to 1000 mb in a volumetric flask. A 25-mL portion of the diluted sample was transferred by pipet into an Erlenmeyer flask and treated with excess KI, oxidizing the OCh to Ch, and producing The liberated was determined by titrating with 0.09892 M NaySyOy, requiting 8.96 mb to reach the starch indicator end point. Report the %w/v NaOCl in the sample of bleach. 

N—Fe(IV)Por complexes. Oxo iron(IV) porphyrin cation radical complexes, [O—Fe(IV)Por ], are important intermediates in oxygen atom transfer reactions. Compound I of the enzymes catalase and peroxidase have this formulation, as does the active intermediate in the catalytic cycle of cytochrome P Q. Similar intermediates are invoked in the extensively investigated hydroxylations and epoxidations of hydrocarbon substrates cataly2ed by iron porphyrins in the presence of such oxidizing agents as iodosylbenzene, NaOCl, peroxides, and air. 

Secondary alcohols are oxidized at room temperature to ketones in high yields by HOCl generated in situ from aqueous NaOCl and acetic acid (109,110). Selective oxidation in the presence of a primary alcohol is possible. In methanol, aldehydes are oxidized to methyl esters (110). Under the proper conditions, alcohols can be esterified with HOCl forming isolable alkyl hypochlorites. 

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. 

Conditions (a) 1-5 mol% catalyst, w-CPBA/NMO, -78°C, CH2CI2. (b) 1-5 mol% catalyst, NaOCl, 4-phenylpyridine iV-oxide, 0°C, CH2CI2. (c) 1-5 mol% catalyst, NaOCl, pyridine iV-oxide, 0°C, CH2CI2. (d) Solvent = diethyl ether... 

Song and Roh investigated the epoxidation of compounds such as 2,2-dimethylchromene with a chiral Mn (salen) complex (Jacobsen catalyst) in a mixture of [BMIM][PFg] and CH2CI2 (1 4 v/v), using NaOCl as the oxidant (Scheme 5.2-12) [62]. 

Redox reactions occur in the reduction of ores (metal oxides) into pure metals and the corrosion (oxidation) of pure metals in the presence of oxygen and water. Rusting iron, 4Fe + 30, + 611,0 —> 4Fe(OH), is a good example of metal oxidation. Strong oxidizing agents can be used as antiseptics (hydrogen peroxide, Fd,0,) or bleaches (sodium hypochlorite, NaOCl). 

For example, the common use of sodium hypochlorite solution, NaOCl, as a bleaching solution depends upon the oxidizing action of hypochlorite, OC1-. Iodate ion, IO, also furnishes a strong oxidizing power, as shown by E° for the half-reaction I2-IO ... 

Scheme 1. Catalytic Cycle for the TEMPO/NaOCl Catalyzed Oxidation...

Figure 25. Bromide-catalyzed oxidation with NaOCl.

Moriarty, R.M. Penmasta, R. Awasthi, A.K. Prakash, I. / Org. Chem., 1988, 53, 6124. Ruthenium tetroxide is an expensive reagent, but the cost can be greatly reduced by the use of an inexpensive cooxidant such as NaOCl, the function of which is to oxidize RUO2 back to ruthenium tetroxide. 

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