Selenid, phenyl

AUylic phenyl selenides are obtained by the reaction of allylic acetates with diphenyldiselenide and Sml2[233]. 

One area of research is the replacement of sulfur with selenium to enhance the potency of organic compounds in pharmaceutical apphcations. This has seldom been successflil and often the toxicity is increased. There are some exceptions, eg, selenazofurin, phenylaminoethyl selenide, ebselen, and selenotifen (64). Selenazofurin is a cytotoxic compound having antitumor properties, phenyl aminoethyl selenide is used to reduce hypertension, ebselen inhibits a variety of inflammatory and tissue damaging reactions, and selenotifen is an antiallergic agent. 

The 7 a-bromo steroid (9) can also be treated with sodium phenyl selenolate (41). The resultant 7 P-phenyl selenide (13) can be oxidized and the corresponding phenyl selenoxide elirninated to form the 7-dehydtocholesteryl ester (11). 

Diseleno acetals and ketals are cleaved more rapidly than their dithio counterparts a methyl derivative is cleaved more rapidly than a phenyl derivative. Methyl iodide or ozone converts diseleno acetals and ketals to vinyl selenides. ... 

Trifluoromethyl thiirane is formed by the action of tris(diethylamino)-phosphineon l-chloromethyl-2,2,2-trifluoroethyldisulfide [S2] (equation 73) Difluoromethyl phenyl selenide is prepared by treatment of lithium phenyl-selemde with chlorodifluoroniethane via a carbene mechanism [Si] (equation 44) Bis(2,2,2-trifluoroethyl)diselenide is formed in the reaction of 2,2,2-trifluoroethyl mesylate with lithium diselenide [84] (equation 74). 

Primare Alkohole konnen leicht fiber Phenyl-selenide durch Reduktion mit Triphenyl-zinnhydrid in Kohlen-wasserstoffe Ubergeffihrt werden6. 

The number of reported reactions in which the radical derived from the decomposition of AIBN plays a role in the termination process has increased considerably. Often these reactions are not radical chain reactions, since the initiator is used in stoichiometric amounts. A few examples of rearomatization of cyclohexadienyl radicals by disproportionation have been reported herein. Below are some other examples, where the phenyl selenide 61 reacts with (TMSfsSiH (3 equiv), AIBN (1.2 equiv) in refluxing benzene for 24 h to give the coupling product of radicals 63 and 64 in good yields (Scheme 9).i24,i25 these cases,... 

Diphenyl diselenide has been prepared by disproportionation of phenyl selenocyanate in the presence of potassium hydroxide" or ammonia/ and by air oxidation of benzeneselenol. The preparation of benzeneselenol is described in an earlier volume in this series/ In the present procedure phenylselenomagnesium bromide formed from phenylmagnesium bromide and selenium is oxidized directly to diphenyl diselenide with bromine/ Thus the liberation of the malodorous and toxic hydrogen selenide and benzeneselenol is avoided. Benzeneselenenyl chloride has been prepared by thermal elimination of ethyl chloride from ethyl phenyl selenide di-chloride/ by thermal elimination of chlorine from phenylselenium trichloride," and by chlorinolysis of diphenyl diselenide with either sulfuryl chloride " or chlorine. " ... 

Ethyl phenyl selenide dichloride Selenium, dichloroethylphenyl-... 

A variety of compounds have been examined which are in the phosphinic acid class. They include a phenyl cyclopentyl ester,184 a phosphinothioic anhydride,185 a dipheny1phosphinamide, 86 a red bis(di-t-buty1thiophosphinamide) and its selenide analogue,187 the anisylphosphor inane (67),1 88 the thioamide (68),1 89 and the phospholenium amide (69, Y = i-Pr2N).190... 

The submitter has synthesized nine alkyl phenyl selenides in yields of 85-95% by treating alcohol solutions of the sodium salt (the selenophenol is dissolved in the calculated amount of 50% aqueous sodium hydroxide diluted with alcohol) with the appropriate alkyl halide or sulfate. 

As has been described for allyl bromide (see preceding paragraph), allyl sulfides and allyl phenyl selenide react with 6-diazopenicillanates 134 under Cu(acac)2 catalysis to give the products of ylide formation and subsequent [2,3] rearrangement 155-159). Both C-6 epimers are formed. The yields are better than with BF3 Et20 catalysis, and, in contrast to the Lewis acid case, no 6[Pg.139]

A derivative of the oxo form of a 3-hydroxyselenophene has been obtained by a quite different route.123 1,5-Diphenyl-1,4-pentadiyn-3-one (94) adds hydrogen selenide and gives a mixture of 2,6-diphenyl-1-seleno-y-pyrone (95) and 2-benzylidene-3-oxo-5-phenyl-2,3-dihydroselenophene (96). 

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