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Benzeneselenenyl halide

Acyloxyselenylation Benzeneselenenyl halides, 26 N-Phenylselenophthalimide, 245 Acyloxysulfenylation Dimethyl(methylthiosulfonium) tetra-fluoroborate, 121... [Pg.353]

Other addition reactions Additions involving carbon Copper(I) chloride, 85 Lithium bis(dimethylphenyl-silyl)cuprate, 161 Manganese(III) acetate, 171 Mercury(II) chloride, 175 2-(Phenylseleno)acrylonitrile, 244 Threophos, 298 Additions involving nitrogen Benzeneselenenyl halides, 26 Additions involving oxygen Bis(Tj5-cyclooctadienyl)ruthe-nium(II), 35... [Pg.354]

N-Phenylselenophthalimide, 245 Additions involving selenium Benzeneselenenyl halides, 26 N-Phenylselenophthalimide, 245 Miscellaneous reagents Aluminum chloride, 15 Lithium bis(dimethylphenyl-silyl)cuprate, 161 Organotin reagents, 211 Addition reactions to carbonyl... [Pg.354]

Benzeneselenenyl halides, 26 Camphor- 10-sulfonic acid, 62 Dicyclohexylcarbodiimide-4-Dimethyl-aminopyridine, 107 Hydrofluoric acid-Acetonitrile, 188 Thiophenol, 297 Lithiation (see Metallation)... [Pg.367]

Benzeneselenenyl halides, 26 N-Benzyl-N-methoxymethyl-N-(trimethylsilyl)methylamine, 31 9-Bromo-9-phenylfluorene, 48 2,3-0-Isopropylidene-2,3-dihydroxy-... [Pg.390]

Containing one nitrogen—pyridines Benzeneselenenyl halides, 26 Containing one nitrogen—other compounds... [Pg.391]

From unsaturated carboxylic acids Benzeneselenenyl halides, 26 Dimethyl(methylthiosulfonium) tetrafluoroborate, 121 By other methods... [Pg.394]

Other a-substituted-a, P-unsaturated carbonyl compounds Benzeneselenenyl halides, 26 P-Substituted-a, p-unsaturated carbonyl compounds... [Pg.398]

PHENOLS Aluminum chloride. Benzeneselenenyl halides. 3-Phenyl thio-... [Pg.314]

Benzeneselenenyl halides, 34-37 Benzeneselenenyl iodide, 36 Benzeneseleninic anhydride, 37—39 Benzenesulfenyl chloride, 39-40 Benzenesulfonyl fluoride, 40 Benzenesulfonylnitrile oxide, 40-41 1 -Benzenesulfonyl-2-trimethylsilylethane, 41-42... [Pg.331]

ALLYL ALCOHOLS Benzeneselenenyl halides. Methylene triphenylphosphorane. Sodium naphthalenide. [Pg.649]

UNSATURATED p-DICARBONYL COMPOUNDS Benzeneselenenyl halides. Selenium. [Pg.652]

Pentacarbonyl(trimethylsilyl)manganese. VINYL FLUORIDES Pyridinium poly(hydrogen fluorideV-N-Bromosuccinimide. VINYLPHOSPHINES 2,4,6-Trii sopropy I benzenesulfonylhy drazine. VINYL SELENIDES Benzeneselenenyl halide-Silver nitrite. Diphosphorus tetraiodide. [Pg.652]

The mechanism of selenocyclization of yS,y-unsaturated acids and their derivatives has been studied. The reactions of ( )-4-phenylbut-3-enoic acid and its silyl and alkyl esters (15 R = H, SiMe3, alkyl) with benzeneselenenyl halide PhSeX (X = Cl, Br) have been examined by VT-NMR and in situ IR spectroscopic methods. Whereas the reactions of the acid in the presence of a base were irreproducible and complicated, reactions of the silyl esters were clean and spontaneously and quantitatively afforded the corresponding chloroselenylation adduct at -70 °C as a single (Markovnikov) isomer. This adduct underwent three processes as the temperature was raised (1) reversal to the starting materials, (2) isomerization to the anti-Markovnikov product, and (3) cyclization to the selenolactone (16). All of these processes are believed to proceed via a seleniranium ion, the intermediacy of which was established by independent synthesis and spectroscopic identification. The reversible formation of chloroselenide adducts was unambiguously established by crossover experiments. The reaction of (15) with PhSeBr was found to be rapid but thermodynamically unfavourable at room temperature.29... [Pg.321]

In summary, several types of carbon >ir-bonds react with benzeneselenenyl halides producing usually one or more regioisomers. Several of these regioisomers may be equilibrated via their sdeniranium ions. [Pg.521]

Oxyselenation ofalkeues, - Treatment of olefins with 1 or 2, water, and an acid catalyst (e.g., p-TsOH) in CH2CI2 affords j3-hydroxy selenides in excellent yield. Unsaturated carboxylic acids, phenols, alcohols, thioacetates, and urethanes react with 1 or 2 and an acid catalyst ( —78- 25°) to afford products of oxidative cyclization. These reagents are superior to benzeneselenenyl halides for selenium-induced ring closures. This reaction is also useful for synthesis of 14- and 16-membered lactones. Benzeneselenenyl halides and benzeneselenenic acid do not promote macrolide formation under similar conditions. [Pg.188]

See other pages where Benzeneselenenyl halide is mentioned: [Pg.73]    [Pg.208]    [Pg.16]    [Pg.470]    [Pg.476]    [Pg.476]    [Pg.477]    [Pg.26]    [Pg.26]    [Pg.390]    [Pg.394]    [Pg.398]    [Pg.22]    [Pg.22]    [Pg.23]    [Pg.649]    [Pg.39]    [Pg.39]    [Pg.40]    [Pg.667]    [Pg.39]    [Pg.39]    [Pg.40]    [Pg.41]    [Pg.585]    [Pg.587]    [Pg.587]   
See also in sourсe #XX -- [ Pg.597 ]

See also in sourсe #XX -- [ Pg.39 , Pg.40 ]

See also in sourсe #XX -- [ Pg.39 , Pg.40 ]



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Lactones Benzeneselenenyl halides

Lactonization Benzeneselenenyl halides

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