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Tris phosphonium

Textile Flame Retardants. The first known commercial appHcation for phosphine derivatives was as a durable textile flame retardant for cotton and cotton—polyester blends. The compounds are tetrakis(hydroxymethyl)phosphonium salts (10) which are prepared by the acid-cataly2ed addition of phosphine to formaldehyde. The reaction proceeds ia two stages. Initially, the iatermediate tris(hydroxymethyl)phosphine [2767-80-8] is formed. [Pg.319]

This reaction gives fair-to-good yields of monoorganotin tribromides and trichlorides when quaternary ammonium or phosphonium catalysts are used (149). Better yields are obtained with organic bromides and staimous bromide than with the chlorides. This reaction is also catalyzed by tri alkyl antimony compounds at 100—160°C, bromides are more reactive than chlorides in this preparation (150,151). a,C0-Dihaloalkanes also react in good yield giving CO-haloalkyltin trihaHdes when catalyzed by organoantimony compounds (152). [Pg.74]

The phosphonium salt method works best with nucleophilic olefins [//, 12, 16, 17, 18, 19] (Table 1 and equations 1-3) and has been used m mechanistically important studies of difluorocarbene additions to norbornadienes [20 21, 22, 23] that provided the first example of a concerted homo-l,4-addition (equation 4) A recent modification uses catalytic 1,4,7,10,13,16 hexaoxacyclooctadecane (18-crown-6) to shorten reaction times and increase yields with less nucleophilic olefins [12] (Table 1) Neither procedure, however, compares with the use of phenyl(tri-f1uoromethyl)mercury or (trifluoromethyl)trimethyltin reagents [efficient reactions with less nucleophilic olefins (equations 3 and 5) and cyclic dienes [24, 25] (equations 6 and 7)... [Pg.767]

BOP.benzotriazol-1 -yloxy-tris(dimethylamino)-phosphonium hexafluorophosphate... [Pg.569]

Sometimes, a direct ion-pairing of the chiral cations and anions 8 or 15 is necessary to maximize the NMR separation of the signals [115,116]. Cationic species as different as quaternary ammonium, phosphonium, [4]heterohelice-nium, thiiranium ions, (rj -arene)manganese, ruthenium tris(diimine) have been analyzed with success (Fig. 23). [Pg.34]

The heats of ionisation and neutralisation of amino and hydroxylic bis and tris phosphonic acids have been investigated.253 Calorimetry in combination with u.v. and n.m.r. spectroscopy uas used to study the adducts of fluoroalkyl carboxylic acids with diethyl phosphonate.254 The heats of formation of the t-butoxytriphenylphosphoranyl radical uas consistent with the phosphonium structure (92).255 There has been a thermal analysis of the adducts of phosphonic and phosphoric acids with... [Pg.415]

Phosphine ignites in cone, nitric acid and addition of warm fuming nitric acid to phosphine causes explosion [1], Phosphonium iodide ignites with nitric acid, and ethylphosphine explodes with fuming acid [2], Tris(iodomercuri)phosphine is violently decomposed by nitric acid or aqua regia [3],... [Pg.1595]

Except for the PBS/SAP-qC16 (n-hexadecyl tri-n-butyl phosphonium cation modified saponite) system, the degree of degradation is the same for other samples. This indicates that MMT or alkylammonium cations, and at the same time other properties, have no effect on the biodegradability of PBS. The accelerated degradation of PBS matrix in the presence of SAP-qC16 may be due to the presence of alkylpho-sphonium surfactant. This kind of behavior is also observed in the case of PLA/MMT-based nanocomposite systems. [Pg.294]

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]

However, compound 57, containing two 1,3-azaphosphetidine fragments, obtained by heating tetrakis(aminomethyl)phosphonium (38) chloride or tris(anilinomethyl)phosphine (40) in ethanol, is described in Eq. (28) (72JOC2752 77JOC4040). A detailed analysis of NMR spectra made it possible to reject a structure with two five-membered rings. [Pg.74]

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]

The derivative 90 was obtained by condensation of the purpurin-18-A-hexylimide-17-propionic acid with aminolactose heptaacetate in the presence of benzotriazol-l-yloxy-tris(dimethylamino)phosphonium hexafluorophosphate (BOP) followed by the deacetylation procedure. The lactose-photosensitiser conjugate linked by an ethylene moiety was also prepared by following a similar approach. The purpurin-18-methyl ester 81 was converted into /V-(3-iodobenzyl)/ /evo-purpurin-18-7V-hexylimide-17-propionic ester by hydrogenation over Pd/C followed by reaction with 3-iodo-benzylamine. Afterwards, the propargyllactose heptaacetate reacted with A-(3-iodobenzyl)rMeio-purpurin-18-A-hexylimide-l 7-propionic ester in the presence of tris(dibenzylidieneacetone)dipalladium(0) (Pd2-dba3) which, after deacetylation conditions, afforded the derivative 89 (Fig. 9).68... [Pg.212]

Anion-based organic dye nanoparticles can be also synthesized on the basis of the ion-association method. In this case, hydrophobic phosphazenium cations such as tetrakis[tris(dimethylamino) phosphoranylideneamino]phosphonium cation are effective for ion-pair formation with anionic dyes. A neutral polymer stabilizer polyvinylpyrrolidone (PVP) that is soluble in water is sometimes added for preventing agglomeration... [Pg.291]

X-Ray.—The crystal and molecular structure of tri-o-tolylphosphine, its oxide, sulphide, and selenide (125) have been compared. The mean P—C bond lengths appear to be determined by the n-electron density along the P—C bond and intramolecular steric interactions, d-Orbital participation was considered to be of little importance.152 X-Ray diffraction established the structure of diphosphinofumarate (126)153 and showed that the phospholanium iodide (127) has an envelope ring with the methyl group at the point of the flap.154 The bicyclic phosphonium bromide (128) has a distorted half-chair phosphorus-containing ring, one of the P—C bonds in the... [Pg.266]

PyBOP benzotriazole-1 -yl-oxy-tris-pyrrolidino-phosphonium hexafluorophosphate... [Pg.579]

In a different approach [11] to access pure products, the use of strong oleum (65% SO3) for sulfonation of PPh3 resulted in quantitative formation of TPPTS oxide. This was converted to the ethyl suhbester through the reaction of an intermediate silver sulfonate salt (isolated) with iodoethane. Reduction with SiHCls in toluene/THF afforded tris(3-ethylsulfonatophenyl)phosphine which was finally converted to pure 3 with NaBr in wet acetone. In four steps the overall yield was 40% (for PPhs) which compares fairly with other procedures to obtain pure TPPTS. Since phosphine oxides are readily available from easily formed quaternary phosphonium salts this method potentially allows preparation of a variety of sulfonated phosphines (e.g. (CH3)P(C6H4-3-S03Na)2). [Pg.24]

World Health Organisation (WHO) (2000) Flame retardants Tris(2-butoxyethyl)phosphate, tris(2-ethylhexyl) phosphate and tetrakis(hydroxymethyl)phosphonium salts. Environmental Health Criteria 218, WHO, Geneva... [Pg.292]


See other pages where Tris phosphonium is mentioned: [Pg.205]    [Pg.121]    [Pg.205]    [Pg.121]    [Pg.126]    [Pg.187]    [Pg.216]    [Pg.158]    [Pg.149]    [Pg.85]    [Pg.239]    [Pg.415]    [Pg.92]    [Pg.278]    [Pg.278]    [Pg.166]    [Pg.329]    [Pg.135]    [Pg.231]    [Pg.199]    [Pg.912]    [Pg.129]    [Pg.136]    [Pg.95]    [Pg.248]    [Pg.51]    [Pg.55]    [Pg.15]    [Pg.172]    [Pg.21]    [Pg.118]    [Pg.110]   
See also in sourсe #XX -- [ Pg.177 ]




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Tris methyl phosphonium

Tris methyl phosphonium iodide

Tris phosphonium ylides

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