Hydrogen peroxide selenides

Hydrogen selenide Hydrogen peroxide, nitric acid... 

Wet chlorination is performed by sparging slimes slurried either in water or hydrochloric acid using chlorine gas, or other oxidants such as sodium chlorate or hydrogen peroxide which Hberate chlorine from hydrochloric acid, at about 100°C. Under these conditions, selenium and selenides rapidly oxidize and dissolve. 

Hydrogen cyanide Calcium cyanide Potassium cyanide Sodium cyanide Hydrogen fluoride as F Hydrogen peroxide Hydrogen selenide as Se Hydrogen sulphide Hydroquinone... 

Caution Most selenium compounds are toxic consequently care should be exercised in handling them. The hydrogen peroxide oxidation of selenides is highly exothermic, acid-catalyzed, and auto-catalytic. The procedure given for adding the hydrogen peroxide solution should be carefully followed. 

A 30% solution of hydrogen peroxide in water was purchased from Mallinckrodt Chemical Works. The reaction requires 2 molar equivalents of hydrogen peroxide, the first to oxidize the selenide to the selenoxide and the second to oxidize the elimination product, benzeneselenenic acid, to benzeneseleninic acid. The submitters recommend that the hydrogen peroxide solution be taken from a recently opened bottle, or titrated to verify its concentration. 

The selenides prepared by any of these methods can be converted to selenoxides by such oxidants as hydrogen peroxide, sodium metaperiodate, peroxycarboxylic acids, 1-butyl hydroperoxide, or ozone. 

See Hydrogen peroxide Hydrogen selenide Nitric acid Non-metal hydrides... 

A solid-phase synthesis of 3-substituted isoxazoles 31 in good yields and purities was achieved by 1,3-DC of polymer-supported vinyl selenide with in situ generated nitrile oxides treatment of intermediate isoxazolines 30 with an excess of hydrogen peroxide resulted in the release of isoxazoles 31 while the use of Mel/Nal led to 3-substituted 5-iodoisoxazolines... 

Tertiary phosphine sulfides are generally stable compounds and are not easily oxidised by air, although they can be oxidised by hydrogen peroxide or dilute nitric acid. The analogous tertiary phosphine selenides and tellurides are however, more reactive to oxidation. Similar to the sulfides they can be prepared from the direct reaction of elemental chalcogen with a tertiary phosphine (Equation 1). Tertiary phosphine selenides are also accessible from tertiary phosphines using KSeCN as the selenium source instead of the element itself. 

Hydrogen selenide Hydrogen sulfide Hydrogen peroxide, nitric acid Fuming nitric acid, oxidizing gases, peroxides... 

Selenium-catalysed epoxidations have been carried out using a perfluo-roalkylated phenylselenide together with hydrogen peroxide, as shown in Scheme 9.6 [13]. The catalyst could be recycled 10 times with no loss of activity, with the toxic selenide immobilized in the perfluorinated solvent. 

Treatment of the selenide (19) with unbuffered 30% hydrogen peroxide-THF yields the cis- and trans-linalyl oxides (247) via [2,3] sigmatropic rearrangement. Kossanyi et al. have improved upon the efficiency of Vig s synthesis of the four lilac alcohols (248). The synthesis of the furanoid (249), formed during sulphuric acid-catalysed dimerization of isoprene, is straightforward. The known half-... 

Oxidation of an a-silyl selenide with hydrogen peroxide leads to an aldehyde, silanol and selenol as the primary products [253]. Evidently, the fragmentation proceeds only after contrapolarization at Se, the intermediate now having an a-d-a array. 

The evidence supplied by the method of formation and the occurrence of isomerism as to analogous structures for the thiosulphates and selenosulphates, is amplified by the chemical behaviour of the potassium alkyl selenosulphates, obtained by treatment of potassium selenosulphates with alkyl halides.1 These, on electrolytic reduction and also on oxidation with hydrogen peroxide, yield the corresponding di-selenides (compare the thiosulphates, p. 203). The structure of the selenosulphates therefore involves a selenium atom directly attached to... 

Selenides (290) and (292) were oxidized to the unstable selenoxides (298) and (299) by aqueous hydrogen peroxide under controlled conditions or by sodium metaperiodate. When selenoxide (298) was subjected to the Pummerer reaction using acetic anhydride in the presence of N- phenylmaleimide, a mixture of exo/endo adducts (144) was obtained in 58% yield, indicating the transient formation of the selenolo[3,4-c]thiophene (143 Scheme 100) <77H(6)1349). 

By elimination reactions of selenides or selenoxides Diphenyl diselenide, 125 Hydrogen peroxide, 145 Other elimination reactions Chloromethyldiphenylsilane, 74 m-Chloroperbenzoic acid, 76 Hydrogen peroxide, 145 Iodomethyltrimethylsilane, 315 Lithium 4,4 -di-/-butylbiphenylide, 162... 

Chlorodiphenyl selenoxide, (ClC6H4)(C6H5)SeO,1 L is isolated as a by-product when phenyl selenide is prepared by the Friedel-Craft reaction. It melts at 94° C. If dibromophenyl selenide is mixed with hydrogen peroxide and hydrochloric acid and the whole treated with a current of air, white crystals are formed which have the composition... 

See Hydrogen peroxide Hydrogen selenide Nitric acid Non-metal hydrides See other ENDOTHERMIC COMPOUNDS, NON-METAL HYDRIDES See related NON-METAL SULFIDES... 

Hydrogen hexaazidothallate(III), 4497 Hydrogen (Liquid), 4448 Hydrogen peroxide, 4471 f Hydrogen selenide, 4480 f Hydrogen sulfide, 4477 f Hydrogen telluride, 4482 Hydrogen trisulfide, 4479... 

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