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Phosphites ammonium

Ammonium orthophosphite. See Ammonium phosphite Ammonium oxalate... [Pg.272]

The primary use for 2,4-di-/ f2 -butylphenol is in the production of substituted triaryl phosphites. 2,4-Di-/ f2 -butylphenol reacts with phosphoms trichloride typically using a trialkylamine or quaternary ammonium salt as the catalyst. Hydrogen chloride is formed and either complexed with the amine or Hberated as free hydrogen chloride gas forming the phosphite ester, tris(2,4-di-/ f2 -butylphenyl)phosphite [31570-04-4] (58). The phosphite-based on... [Pg.68]

Zinc chloride is a Lewis acid catalyst that promotes cellulose esterification. However, because of the large quantities required, this type of catalyst would be uneconomical for commercial use. Other compounds such as titanium alkoxides, eg, tetrabutoxytitanium (80), sulfate salts containing cadmium, aluminum, and ammonium ions (81), sulfamic acid, and ammonium sulfate (82) have been reported as catalysts for cellulose acetate production. In general, they require reaction temperatures above 50°C for complete esterification. Relatively small amounts (<0.5%) of sulfuric acid combined with phosphoric acid (83), sulfonic acids, eg, methanesulfonic, or alkyl phosphites (84) have been reported as good acetylation catalysts, especially at reaction temperatures above 90°C. [Pg.253]

Besides Fe-, other reducing agents that may be used in conjunction with H2O2 are aliphatic amines, Na2S203 thiourea, ascorbic acid, glyoxal, sulfuric acid, NaHSOs, sodium nitrite, ferric nitrate, peroxidase, AgNOs, tartaric acid, hydroxylamine, ethylene sulfate, sodium phosphite, formic acid, ferrous ammonium sulphate, acetic acid, ferrous sulphate, and HNO2, etc,... [Pg.489]

Phosphites, D. of as ammonium magnesium phosphate or as magnesium pyrophosphate, (g) 497 as mercury(I) chloride by mercury(II) chloride, (g) 486 Phosphorescence 731... [Pg.870]

Ammonium phosphite (NlLtiHPOj 116.06 51503-61-8 Sodium potrmetaphosphate (NaPOj), > n. 101.96 508I3-I6-6 Polassium pyrophosphate KjPjO, 330.34 7320-34-5... [Pg.366]

Ammonium sulphide DIammonium phosphite Diammonium phosphate... [Pg.463]

The most general method for the simultaneous analysis of oxyanions by gas chromatography is the formation of trimethylsilyl derivatives. Trimethylsilyl derivatives of silicate, carbonate, oxalate, borate, phosphite, phosphate, orthophosphate, arsenite, arsenate, sulfate and vanadate, usually as their ammonium salts, are readily prepared by reaction with BSTFA-TMCS (99 1). Fluoride can be derivatized in aqueous solution with triethylchlorosilane and the triethylfluorosilane formed extracted into an immiscible organic solvent for analysis by gas chromatography [685). [Pg.959]

The thermal synthesis of nucleoside-5 -phosphite monoester using (NH HPCb was carried out under relatively mild conditions (60°C, reaction time about 24 h) by A. W. Schwartz s group in Nijmegen, Holland in the case of uridine, the yield was 20%. Ammonium phosphate, however, cannot be used it gave yields of only 0.15% after very long reaction times (46 days). This confirms earlier suggestions that nucleoside-H-phosphonates, and condensation products possibly derived from them, would have been formed more readily on the primeval Earth than nucleotides (de Graaf and Schwartz, 2005). [Pg.149]

Dibasic forms of phosphorus (III) species also have been reported to undergo Michael-type additions to unsaturated substrates. Hypo-phosphorous acid adds to acrylamides to generate free phosphonous acids in good yield,430 as well as to vinyl acetate.431 Further, methyl hypophosphite adds to a variety of unsaturated substrates,432 as does the ammonium salt of mono(2-ethylhexyl) phosphite (Equation 3.27).433... [Pg.65]

Diethyl phosphate esters of the sterically congested phenols of calixarenes have been prepared in acceptable yields (>55%) and used in the preparation of meta-cyclophanes [8]. The corresponding reaction using diethyl phosphite, with triethylamine in place of the quaternary ammonium catalyst, results in only partial phosphorylation of the hydroxyl groups. [Pg.110]

First phosphitylation was performed by 0-benzyl-bis(iV,iV,-diisopropyl)-phosphoroamidite in the presence of diisopropyl-ammonium tetrazolide at room temperature in dichloromethane solution (step a). The intermediate phosphoroamidite was coupled with a glycerol moiety in the presence of tetrazole in boiling CH2CI2 to give the benzyl phosphite (step b), which was oxidized by CPBA in CH2CI2 into the corresponding phosphate (step c). In the final step d total debenzylation was achieved by Pd/C transfer hydrogenol-ysis in the presence of formic acid and methanol at room temperature. [Pg.119]

Tertiary and aromatic nitroso compounds are not readily accessible consequently not many reductions have been tried. Nitrosobenzene was converted to azobenzene by lithium aluminum hydride (yield 69%) [592], and o-nitrosobiphenyl to carbazole, probably via a hydroxylamino intermediate, by treatment with triphenylphosphine or triethyl phosphite (yields 69% and 76%, respectively) [298]. Nitrosothymol was transformed to amino-thymol with ammonium sulfide (yield 73-80%) [245], and a-nitroso-/J-naphthol to a-amino-/J-naphthol with sodium hydrosulfite (yield 66-74%) [255]. [Pg.75]

Dihydrogen phosphate (H PO,-) Hydrogen phosphate (HPO/i Phosphite (POj ) Ammonium (NH +)... [Pg.84]

Notice in Table 6-1 that all the common polyatomic ions except ammonium have a negative charge ranging between -1 and -3. You also see a number of -ite/-ate pairs, such as chlorite and chlorate, phosphite and phosphate, and nitrite and nitrate. If you look closely at these pairs, you notice that the only difference between them is the number of oxygen atoms in each ion. Specifically, the -ate ion always has one more oxygen atom than the -ite ion but has the same overall charge. [Pg.85]

Harada et al. studied the TiO2 photocatalytic mineralization of trimethyl phosphate, trimethyl phosphite, and O, (9-dimethyl ammonium phosphodithioate and reported excellent mass balance based on phosphate, sulfate, and carbon dioxide produced after prolonged illumination [39]. Subsequent studies found the organophosphorus insecticides dimethyl-2,2-dichlorovinyl phosphate [Eq. (5)] and di-methyl-2,2,2-trichloro-I-hydroxyethyl phosphonate were mineralized by solar irradiation in the presence of suspended TiO2 [40] ... [Pg.236]

Ammonium salts of sulfonated phenyl phosphites, which are surprisingly resistant to hydrolysis, have been prepared (25). The compounds are more water stable than triphenyl phosphite, but they decompose completely within 24 h. [Pg.477]

Aluminum bromide AlBr3 is used as a catalyst and parallels AICI3 in this role. Strontium and magnesium bromides are used to a limited extent m phamiacentical applications. Ammonium bromide is nsed as a flame retardant in some paper and textile applications potassium bromide is used in photography. Phosphorus tribromidc PBr3 and silicon tetrabromide SiBi4 are nsed as intermediates and catalysts, notably in the production of phosphite esters. [Pg.258]

H. Stamm also measured the solubilities of the salts of the alkalies in liquid ammonia —potassium hydroxide, nitrate, sulphate, chromate, oxalate, perchlorate, persulphate, chloride, bromide, iodide, carbonate, and chlorate rubidium chloride, bromide, and sulphate esesium chloride, iodide, carbonate, and sulphate lithium chloride and sulphate sodium phosphate, phosphite, hypophosphite, fluoride, chloride, iodide, bromate, perchlorate, periodate, hyponitrire, nitrite, nitrate, azide, dithionate, chromate, carbonate, oxalate, benzoate, phtnalate, isophthalate ammonium, chloride, chlorate, bromide, iodide, perchlorate, sulphate, sulphite, chromate, molybdate, nitrate, dithionate, thiosulphate, persulphate, thiocyanate, phosphate, phosphite, hypophosphite, arsenate, arsenite, amidosulphonate, ferrocyanide, carbonate, benzoate, methionate, phenylacetate, picrate, salicylate, phenylpropionate, benzoldisulphonate, benzolsulphonate, phthalate, trimesmate, mellitate, aliphatic dicarboxylates, tartrate, fumarate, and maleinate and phenol. [Pg.204]


See other pages where Phosphites ammonium is mentioned: [Pg.137]    [Pg.137]    [Pg.257]    [Pg.281]    [Pg.54]    [Pg.71]    [Pg.104]    [Pg.113]    [Pg.361]    [Pg.1478]    [Pg.315]    [Pg.872]    [Pg.234]    [Pg.310]    [Pg.275]    [Pg.493]    [Pg.281]    [Pg.300]    [Pg.361]    [Pg.220]    [Pg.357]    [Pg.705]    [Pg.788]    [Pg.877]    [Pg.880]    [Pg.882]    [Pg.888]    [Pg.911]   
See also in sourсe #XX -- [ Pg.911 ]




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Ammonium phosphite

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