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Benzene phosphonous acid

PSVBDEP poly(styrene-co-4-vinyl benzene phosphonic acid diethyl ester) PVAc poly(vinyl acetate)... [Pg.124]

The current intensified interests in the preparation of PEMs have prompted us to synthesize aromatic monomers such as trifluorovinyl ethers functionalized by acid groups. In particular, we reported the first preparation of 4-[(a,, -trifluorovinyl)oxy] benzene phosphonic acid (Fig. 2.21) [99]. [(a,, -Trifluorovinyl)oxy]benzene dialkyl phosphonate was prepared by several phosphonation methods, such as Michaehs-Arbuzov, Michaelis-Becker, or palladium-catalyzed arylation in the presence of various reactants. The reaction involving palladium triphenylphosphine as the catalyst led to the best yield [99]. [Pg.63]

A) The preparation of [H-chloroethoxyjchloromethyl]phosphonic acid Acetaldehyde (1.1 mol) and hydroxymethylphosphonlc acid (1 mol) in 500 ml of benzene are saturated with hydrogen chloride gas at 10°C to 15°C. The mixture is aged at 25°C for 24 hr, the solvent distilled out in vacuo and the residue flushed three times with benzene to remove all traces of hydrogen chloride. The residue is taken up in benzene (500 ml), treated with tert-butyl hypochlorite (0.8 mol) and azobisisobutyronitrile (0.8 mm) at 40°C until titration shows the absence of hypochlorite and the solution is then evaporated to yield [(1-chloro-ethoxy)chloromethyll phosphonic acid in the form of an oil. [Pg.703]

Aliphatic phosphoric acid and phosphonic acid amides containing lipophilic groups were prepared and used as antimicrobial surfactants. For example, 100 g ethylmethanephosphonate chloride was added to a solution of 130 g dodecyl-amine and 72 g triethylamine in 500 ml anhydrous benzene at 20-30°C to give 192 g ethylmethanephosphonate N-dodecylamide [125]. [Pg.579]

From (IV), chlorosulphonic acid (V) and benzene sulphonic acid (VI) are obtained by the replacement of H by Cl and C6H5 respectively Arguing along similar lines, (VIII) is phosphonic acid and (IX) is fluorophosphonic acid, hence (I) is diethyl chlorophosphonate. Th ... [Pg.35]

Only a few systematic studies have been carried out on the mechanism of interaction of organic surfactants and macromolecules. Mishra et al. (12) studied the effect of sulfonates (dodecyl), carboxylic acids (oleic and tridecanoic), and amines (dodecyl and dodecyltrimethyl) on the electrophoretic mobility of hydroxyapatite. Vogel et al. (13) studied the release of phosphate and calcium ions during the adsorption of benzene polycarboxylic acids onto apatite. Jurlaanse et al.(14) also observed a similar release of calcium and phosphate ions during the adsorption of polypeptides on dental enamel. Adsorption of polyphosphonate on hydroxyapatite and the associated release of phosphate ions was investigated by Rawls et al. (15). They found that phosphate ions were released into solution in amounts exceeding the quantity of phosphonate adsorbed. [Pg.312]

Functionalized polymers are of interest in a variety of applications including but not limited to fire retardants, selective sorption resins, chromatography media, controlled release devices and phase transfer catalysts. This research has been conducted in an effort to functionalize a polymer with a variety of different reactive sites for use in membrane applications. These membranes are to be used for the specific separation and removal of metal ions of interest. A porous support was used to obtain membranes of a specified thickness with the desired mechanical stability. The monomer employed in this study was vinylbenzyl chloride, and it was lightly crosslinked with divinylbenzene in a photopolymerization. Specific ligands incorporated into the membrane film include dimethyl phosphonate esters, isopropyl phosphonate esters, phosphonic acid, and triethyl ammonium chloride groups. Most of the functionalization reactions were conducted with the solid membrane and liquid reactants, however, the vinylbenzyl chloride monomer was transformed to vinylbenzyl triethyl ammonium chloride prior to polymerization in some cases. The reaction conditions and analysis tools for uniformly derivatizing the crosslinked vinylbenzyl chloride / divinyl benzene films are presented in detail. [Pg.97]

This specifity is dependent on the acidity of the catalyst, and was studied using the heterogeneous catalysts sulfonated and phosphonated poly benzene, and the homogeneous catalysts paratoluenesulfonic acid and phosphoric acid. The differences between the sulfonic and phosphonic acid groups were greater than the differences between heterogeneous and homogeneous phase, in spite of a considerable difference in reaction temperature. It was thus shown that for a typical Class A reaction, the type of acidity is more important than the physical state of the catalyst. These acidic catalysts were extremely active, and had to be partially neutralized in order to obtain reasonable rates ans selective reactions. [Pg.28]

The synthesis of multidentate Lewis acids is of great interest [102]. The photostimulated reactions of [o-(diethoxy-phosphoryl)-phenyl]-phosphonic acid diethyl ester with Me3Sn- ions in liquid ammonia affords the disubstitution product 6>-Z f -trimethylstannanyl-benzene 29a in 67% yield [103]. Under the same experimental conditions, 2,2/-Zus(diethylphosphoxy)-1,1 -binaphthyl 30 affords the disubstitution product 31 in high yields (Sch. 28) [103]. [Pg.512]

Another important source of chiral auxiliaries for the synthesis of optically active phosphorus derivates are the C2 symmetric diamines such as 1,2-diaminocyclohex-anes. In 1994, Hanessian and co-workers described the use of A,/V -dimethyl-(R,R)-1,2-diaminocyclohexane 93 as a chiral auxiliary in the synthesis of optically pure or enantiomerically enriched a-alkyl a-amino phosphonic acids [49], Starting from easily accessible optically pure diamine 93, they synthesized in good yield (75 %) enantiomerically pure (R,R)-ethylphosphonamide 94 by condensation with ethyl phosphonic dichloride in benzene in the presence of triethylamine (Scheme 43). [Pg.94]

DIETHYL (DICHLOROMETHYL)PHOSPHONATE. PREPARATION AND USE IN THE SYNTHESIS OF ALKYNES (4-METHOXYPHENYL)ETHYNE (Phosphonic acid, (dichloromethyl)-, diethyl ester to prepare Benzene, 1-ethylnyl-4-methoxy-)... [Pg.108]

The reaction between white phosphorus, oxygen and cyclohexene in benzene solution yielded a product with the empirical formula CgHj 0P2O4 which hydrolyzed in the presence of oxygen to cyclohexene-l-phosphonic acid, (28) ... [Pg.46]

It should be noted that co-acetoxyalkylphosphonates [82] and co-acetoxyalkyl-phosphonic acids of different structures include carbohydrate-derived compounds [83] and that substituted phosphorylated benzenes [58] also afford the corresponding 2-oxo-l,2-phosphacyclanes under acid catalysis. Subsequent treatment of the cyclic... [Pg.128]

Phosphorus(v) oxide reacts at 275-325° with aromatic hydrocarbons such as benzene, toluene, and naphthalene, and also with chlorobenzene, giving phosphonic anhydrides which are preferably worked up by hydrolysis to the phosphonic acids.170 Phosphorus(v) sulfides react at appreciably lower temperatures, yielding dithiophosphonic anhydrides (9) the... [Pg.715]

Within this area, the most recent developments in the synthesis of esters of phosphonic acids have been the direct alkylation of hydrogenphosphonates using diazoalkanes in the presence of copper-containing catalysts in benzene as the solvent Of those catalysts examined, the most effective seem to be [Cu(acac)2] and [Cu(OTf)2], with Cu, Pd and Rh acetates and [Ni(acac)2] being less effective. The overall reaction is that represented in equation 18, in which R and R may be H, Ph or a simple alkyl group, but they may also consist of a functionalized alkyl group in reactions catalysed by trifluoromethanesul-phonic acid A similar procedure has been applied to the hydrogenphosphinate Ph(MeO)P(0)H ... [Pg.69]

The early literature describes examples of elimination reactions of a rather forcing nature which have not been explored further. For example, the elimination of HCl from (2-chloroethyl)phosphonic dichloride occurs over BaCl2 at 330 and dechlorination of (l,2-dichloroethyl)phosphonic diesters occurs on heating with zinc dust. Dehydrochlorination of a (2-chloroalkyl)phosphonic acid occurs on simple pyrolysis but the preferred procedure consists in the treatment of the acid diester with Et3N in warm benzene, a procedure also used for analogous (2-chloroethyl)phosphinic esters ". The dehydro-halogenation of isopropyl (2-haloethyl)phenylphosphinate by a chiral tertiary amine, such as quinine, quinidine, 1 -phenylethylamine or A-methylephedrine, in a less than equivalent quantity, affords an enrichment of one enantiomer of the ethenylphenylphosphinic... [Pg.120]

The phosphoryl group evidently, and not surprisingly, deactivates an attached benzene ring during electrophilic substitution reactions the sulphonation (with SO3) of phenylphosphonic acid leads initially to the 3-sulphonic acid, and subsequently at 180-240 °C to the 3,5-disulphonic acid. The nitrations of (4-chlorophenyl- or (4-bro-mophenyl)-phosphonic acids have given products described as the 3-nitro derivatives, but it has also been stated that the nitration of dimethyl phenylphosphonate gives dimethyl (4-nitrophenyl)phosphonate, a pattern of substitution certainly observed in the nitration of... [Pg.498]

Benzene, (1-methylethenyl)-, homopolymer. See Poly-a-methylstyrene Benzene, 1-methyl-4-(1-methylethy )-. See p-Cymene Benzene monochloride. See Chlorobenzene Benzenenitrile. See Benzonitrile Benzene, pentabromoethyl-. See Pentabromoethylbenzene Benzenephosphonic acid. See Phenyl phosphonic acid Benzenepropanoic acid, 3,5-bis (1,1-dimethylethyl)-4-hydroxy-. See Pentaerythrityl tetrakis [3-(3, 5 -di-t-butyl-4-hydroxyphenyl) propionate] Benzenepropanoic acid, 3,5-bis (1,1-dimethylethy )-4-hydro]qf-, thiodi-2,1-, ethanediyi ester. SeeThiodiethylene bis (3,5-di-t-bulyl-4-hydro) ) hydrocinnamate... [Pg.988]

Hydroxy-2,2,2-trichloroethylphosphonic acid dimethyl ester (2,2,2-Trichloro-1-hydroxyethyl) dimethylphosphonate 2,2,2-Trichloro-1-hydroxyethylphosphonate, dimethyl ester (2,2,2-Thchloro-l-hydroxyethyl) phosphonic acid dimethyl ester Trichlorophon Trichlorphene Trichlorphon Empirical C4H8CI3O4P Formula (CH30)2P(0)CH(OH)CCl3 Properties Wh. cryst. solid sol. in water, alcohols, ketones, benzene, chloroform, ether si. sol. in aromatic soivs., petrol, ether insol. in oils m.w. 257.45 dens. 1.73 (20/4 C) m.p. 83-84 C b.p. [Pg.4484]


See other pages where Benzene phosphonous acid is mentioned: [Pg.242]    [Pg.130]    [Pg.28]    [Pg.961]    [Pg.1714]    [Pg.49]    [Pg.1377]    [Pg.903]    [Pg.434]    [Pg.219]    [Pg.337]    [Pg.10]    [Pg.69]    [Pg.90]    [Pg.112]    [Pg.327]    [Pg.458]    [Pg.214]    [Pg.623]    [Pg.3002]    [Pg.5016]    [Pg.102]   
See also in sourсe #XX -- [ Pg.340 ]




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