2- Phenylseleno

The Homer - Emmons reagent (52) is effective in the one carbon homologation of ketones possessing acidic a-hydrogen atoms <96SL875> and electron-deficient alkenes add to 2-phenylseleno-l,3-dithiane in a photo-initiated heteroatom stabilised radical atom transfer process, giving products of considerable synthetic potential <96TL2743>. [Pg.308]

Interestingly, attempts to apply this cyclization reaction to linear diolelins using an alcoholic solvent give unsatisfactory results. Cyclic ethers have instead been obtained in aqueous acetonitrile. Under these conditions 1,5-hexadiene gives a 91 9 mixture of 2,5-bis[(phenylseleno)methyl]tetrahydrofuran and 2-[(phenylseleno)methyl]-5-(phenylseleno) tetrahydropyran in 86% yield (equation 144). [Pg.625]

Die Oxidation von 1-Trimethylsilyl-benzimidazol mit Benzolselenylchlorid soil iiber einen pri-maren Angriff des Selen-Atoms am N-Atom erfolgen. Unter Abspaltung von Chlor-trimethyl-silan wird 2-Phenylseleno-benzimidazol (93% Schmp. 131-135°) erhalten401 ... [Pg.326]

N-(4-Pentenyl)-acetamide konnen als Ausgangsmaterial zur Synthese von 2-Methyl-pyrrolidinen eingesetzt werden. Hire Kondensation mit Phenylselenenyl-bromid und De-phenylselenylierung des so erhaltenen 2-(Phenylseleno-methyl)-pyrrolidin-Derivates fuhrt zum l-Acetyl-2-methyl-pyrrolidin3, das in bekannter Weise (s.S. U87ff. sowie Bd. XI/1, S. 926) zum freien Amin (d. h. z. B. zu 2-Methyl-pyrrolidin oder 4-Ethyl-2-methyl-pyrrolidin) gespalten werden kann. [Pg.1088]

Butene 3-Fluoro-2-phenylseleno-ElOa, 133(IIF + Ar-Se-NR2) E10b 380 (In + XeF2/... [Pg.675]

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]

Phenylseleno) acrylonitrile, 244 Tetrakis(triphenylphosphine)palla-dium(0), 289... [Pg.357]

Lithium butyldimethylzincate, 221 Lithium sec-butyldimethylzincate, 221 Organolithium reagents, 94 Organotitanium reagents, 213 Palladium(II) chloride, 234 Titanium(III) chloride-Diisobutylalu-minum hydride, 303 Tributyltin chloride, 315 Tributyl(trimethylsilyl)tin, 212 3-Trimethylsilyl-l, 2-butadiene, 305 Zinc-copper couple, 348 Intramolecular conjugate additions Alkylaluminum halides, 5 Potassium t-butoxide, 252 Tetrabutylammonium fluoride, 11 Titanium(IV) chloride, 304 Zirconium(IV) propoxide, 352 Miscellaneous reactions 2-(Phenylseleno)acrylonitrile, 244 9-(Phenylseleno)-9-borabicyclo[3.3.1]-nonane, 245 Quina alkaloids, 264 Tributyltin hydride, 316 Conjugate reduction (see Reduction reactions)... [Pg.361]

Reductive coupling of carbonyls to alkenes Titanium(IV) chloride-Zinc, 310 of carbonyls to pinacols Titanium(III) chloride, 302 Titanium(IV) chloride-Zinc, 310 of other substrates Samarium(II) iodide, 270 Reductive cyclization 2-(Phenylseleno)acrylonitrile, 244 Tributylgermane, 313 Tributyltin hydride, 316 Triphenyltin hydride, 335 Trityl perchlorate, 339 Reductive hydrolysis (see Hydrolysis) Reductive silylation Chlorotrimethylsilane-Zinc, 82... [Pg.373]

Bis(l, 5-cyclooctadiene)nickel(0), 35 t-Butyllithium, 58 Diacetatobis(triphenylphosphine)-palladium(II), 91 Menthol, 172 Mercury(II) chloride, 175 Palladium(II) acetate, 232 2-(Phenylseleno)acrylonitrile, 244 Potassium t-butoxide, 252 Tributyltin hydride, 316 Triphenyltin hydride, 335... [Pg.379]

Initially, the de novo synthesis of enantiomerically pure carbohydrates [110] and glycolipids [111] using transition metal complexes and chiral auxiliaries afforded only modest success. Ultimately, it was the use of enantiomerically pure aldehydes, such as the R and S enantiomers of 2-(phenylseleno)propionaldehyde, to convey facial selectivity upon the LACDAC reaction that enabled the synthesis of optically pure glycals. Syntheses of several complex monosaccharides such as the main sialic acid-type N-acetylneuraminic acid (Neu5Ac) and rac-3-deoxy-ma o-2-octulosonic acid (KDO) were accomplished with this technology [112, 113], The LACDAC... [Pg.20]

Phenylseleno)acetaldehyde was recommended as an alternative synthetic equivalent to the vinyl carbocation for a-vinylation of ketones [30],... [Pg.80]

The reaction of enamines and imines with acrylamide results in aza-annulation120,121. Other electrophilic alkenes which have been used to alkylate enamines and the products used in hetero- or carbocyclic synthesis include ethyl / -nitroacrylate122, where reaction occurs beta to the nitro not the ester group, 2-(phenylseleno)prop-2-enenitrile [CH2 = C(SePh)CN]123,124, phenyl a-phenylselenovinyl sulphone [CH2 = C(SePh)-S02Ph]124 and phenyl a-bromovinyl sulphone124. An electrophilic allene, phenylsulpho-nylpropadiene, has also been used to alkylate enamines125 (Scheme 44). [Pg.760]

Propanol 2-Nitro-2-phenylseleno-E16d, 216 (CH —N02 + CH20) E19d, 1037 (Nitronat + CH20)... [Pg.625]

Butan 3-Azido-2-phenylseleno-E21e, 5216 (En + Ar-SeCl/ NaN3)... [Pg.767]

Telluran(IV) (2-Phenylseleno-phenyl)-trichloro- E12b, 862 (HgCl - TeCl3)... [Pg.969]

Butan 3-Acetamino-2-phenylseleno-E21e, 5113 (En - NHAc/SeAr)... [Pg.1043]

Phenyl-2-(phenylseleno)propanal (10, Ar = CfiH,) Typical Procedure7 ... [Pg.589]

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