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Tris phosphine, reaction with

The preparation of chelating surface-active diphosphines proved to be more successful. The BDPP analogue R,R-(9) was synthesized by lithiation of tris[p-(3-phe-nylpropyl)phenyl]phosphine, reaction with (R,R)-2,4-pentane-diylditosylate and subsequent sulfonation with concentrated sulfuric acid [16]. Hydrogenation of the prochiral olefin (Z)-2-(N-acetamido)cinnamic acid ester in a two-phase system (ET0Ac/H20) with Rh complexes derived from R,R-(9) was accomplished with identical selectivity compared with the unsulfonated BDPP and improved reactivity compared with BDPPTS (2). [Pg.180]

The mixed triarylphosphine 787 can be prepared by the reaction of (trimethylsily )dipheny phosphine (786) with aryl halides[647]. Ph3P is converted into the alkenylphosphonium salt 788 by the reaction of alkenyl tri-flates[648]. [Pg.244]

Tri-(l-naphthyl)phosphine is cleaved by alkali metals in THF solution. " Reaction with sodium gives the naphthalene radical-ion, with lithium the perylene radical-ion, and with potassium the radical-ion (22). Hydrocarbon radical-ion formation was thought to occur via naphthalene derived from the metal naphthalenide. E.s.r. spectra of further examples of phosphorus-substituted picrylhydrazyl radicals have been reported. ... [Pg.235]

Alcohols can be converted to o-nitrophenylselenides by reaction with o-nitrophenyl selenocyanate and tri( -butyl)phosphine.329... [Pg.599]

All these complexes readily undergo ligand exchange reactions [65], including substitution of [TcNCl2(PPh3)2] by more basic phosphines [3]. Tri(cyanoethyl) phosphine (L) yields the anionic NBu4TcNX3L] (X = Cl, Br) on reaction with... [Pg.50]

Use of tris(trimethylsilyl)phosphine as the phosphorus furnishing reagent in condensation reaction with a-diazocarboxylic chlorides (7) gave 2-trimethylsilyl-[l,2,3]diazaphospholes (9) in good yields (Scheme 3) [18],... [Pg.178]

The main method for obtaining these heterocycles is the interaction of amines with oxymethylphosphines. Frank and Drake (72JOC2752 77JOC4040) isolated 5-aminomethyl-l,3-diphenyl-l,3,5-diazaphosphori-nane (39) by treating tris(oxymethyl) phosphine (40) or tetrakis(oxy-methyl)phosphonium chloride (38) with aniline. The reaction with p-toluidine proceeds in a similar manner [Eq. (24)] (83IZV1379). [Pg.72]

Larger chalcogen-phosphorus heterocycles, although less common in the literature, are accessible via a variety of synthetic routes.2,83,84 For example, the cyclic trimer (SPR)3 (R = 2,4,6-tri-tert-butylphenyl) contains a puckered six-membered P3S3 ring and is produced in the reaction of a phosphinic chloride with lithium sulfide (Equation 73).98 Additionally (R P)3Se5 (R = 2,4-di-tert-butyl-6-wopropoxyphenyl), synthesised from the oxidation of a primary phosphine with three equivalents of elemental selenium (Equation 74), has... [Pg.311]

Heck tried the reductive dimerization of isoprene in formic acid in the presence of triethylamine at room temperature using 1% palladium phosphine catalysts to give dimers in up to 79% yield (95). Better selectivity to the head-to-tail dimer was obtained by using Pd(OAc)2 with 1 1 ratio of arylphosphines. THF as solvent showed a favorable effect. In a scaled-up reaction with 0.5 mole of isoprene using 7r-allylpalladium acetate and o-tolyphosphine, the isolated yield of the dimers was 87%. The dimers contained 71% of the head-to-tail isomers. The mixture was converted into easily separable products by treatment with concentrated hydro-... [Pg.172]

The selective activation of the primary hydroxyl group in methyl a-D-glucopyranoside by reaction with carbon tetrachloride and tris(dimethylamino)phosphine in A/.N-dimethylformamide at —40° has been reported.381 An alkoxytris(dimethylamino)phosphonium... [Pg.79]


See other pages where Tris phosphine, reaction with is mentioned: [Pg.258]    [Pg.319]    [Pg.40]    [Pg.167]    [Pg.927]    [Pg.274]    [Pg.127]    [Pg.54]    [Pg.111]    [Pg.927]    [Pg.40]    [Pg.181]    [Pg.307]    [Pg.677]    [Pg.1170]    [Pg.172]    [Pg.497]    [Pg.157]    [Pg.517]    [Pg.345]    [Pg.409]    [Pg.40]    [Pg.55]    [Pg.315]    [Pg.93]    [Pg.172]    [Pg.172]    [Pg.113]    [Pg.179]    [Pg.35]    [Pg.366]    [Pg.191]    [Pg.247]    [Pg.304]    [Pg.363]    [Pg.363]    [Pg.179]   


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B Reaction of Pyrylium Salts with Tris-(trimethylsilyl)-phosphine

Phosphines reaction

Reaction with phosphines

Reactions phosphination

Tri phosphine

Tris phosphine

Tris phosphine, reaction

Tris phosphine, reaction with adducts

Tris phosphine, reaction with aryl lithiums

Tris- phosphine reaction with molybdenum

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