Alkyl phosphates, preparation

Alkyl phosphates, preparation, 16, 9 Alkyl sulfides, preparation, 15, 72 JV-Alkyl- -toluidines, 18, 42 Allantoin, 13,1... 

Alkyl phosphates, preparation, 16, 9 Alkyl sulfates, preparation, 19, 27 Alkyl sulfides, preparation, 15, 72 Alkyl sulfites, preparation, 19, 29 Ai-AlkyW -toluidines, 18,42 Allanioin, 13,1 Allyl alcohol, 10, 107 16, 85 Allylamine, 18, 5 Allyl cyanide, 16, 85 Allyl isothiocyanate, 18, 5 Alumina, 17, 27... 

Early preparation of metallic phosphides Named the mineral apatite Prepared PCI3 and PCI3 Lecithin isolated from brain fat Alkyl phosphates prepared... 

The above is a general procedure for preparing trialkyl orthophosphates. Similar yields are obtained for trimethyl phosphate, b.p. 62°/5 mm. triethyl phosphate, b.p. 75-5°/5 mm. tri-n-propyl phosphate, b.p. 107-5°/5 mm. tri-Mo-propyl phosphate, b.p. 83-5°/5 mm. tri-wo-butyl phosphate, b.p. 117°/5-5 mm. and tri- -amyl phosphate, b.p. 167-5°/5 mm. The alkyl phosphates are excellent alkylating agents for primary aromatic amines (see Section IV,41) they can also be ua for alkylating phenols (compare Sections IV,104-105). Trimethyl phosphate also finds application as a methylating agent for aliphatie alcohols (compare Section 111,58). 

In addition to their poor solubility in water, alkyl phosphate esters and dialkyl phosphate esters are further characterized by sensitivity to water hardness [37]. A review of the preparation, properties, and uses of surface-active anionic phosphate esters prepared by the reactions of alcohols or ethoxylates with tetra-phosphoric acid or P4O10 is given in Ref. 3. The surfactant properties of alkyl phosphates have been investigated [18,186-188]. The critical micelle concentration (CMC) of the monoalkyl ester salts is only moderate see Table 6 ... 

Salts of alkyl phosphates and types of other surfactants used as emulsifiers and dispersing agents in polymer dispersions are discussed with respect to the preparation of polymer dispersions for use in the manufactoring and finishing of textiles. Seven examples are presented to demonstrate the significance of surfactants on the properties, e.g., sedimentation, wetting behavior, hydrophilic characteristics, foaming behavior, metal adhesion, and viscosity, of polymer dispersions used in the textile industry [239]. 

Mesoporous zirconia has been prepared using anionic surfactants containing reactive oxygens that could bind Zr2+ (224-226). Mesoporous zirconia was obtained using alkyl phosphate amphiphiles but they were not stable to template removal. 

Materials and Method. Aqueous solutions of disodium alkyl phosphates were prepared by dissolving the corresponding acids in sodium hydroxide solutions. The alkyl phosphoric acids were synthesized by the reaction of pyrophosphoric acid with the respective alcohol in benzene at room temperature for A days. Details of the purification procedures are given elsewhere(7). 

Observations were made of lipid-protein phases in which the structure is determined mainly by the protein. Raman spectroscopy is a useful method for structure analysis of such phases. The structures described above were analyzed successfully by an x-ray diffraction technique. Lipid-protein complexes, however, are often amorphous, and alternative methods to study their structures are therefore needed. It was demonstrated that Raman spectroscopy can be used to obtain structural information about lipid-protein interaction (16, 17). It is thus possible to determine the conformation as well as the type of environment of the lipid molecules. With the protein, interpretation is more complicated. It is usually possible to determine whether the complex has the same protein conformation as the component used in the preparation, or, if a change occurs, it may be possible to correlate it with denaturation of the pure protein. For complexes formed by long-chain alkyl phosphates and insu-... 

It is desirable to avoid errors in pH measurement, which limit the accuracy of the above NMR pH titration. If an NMR titration is applied to a mixture of two acids, HA and HA, each of whose chemical shifts, 6 and S, follows Equation (13), it is possible to eliminate pH from the two equations and replace it with n, the number of equivalents of titrant added. Thus Ellison and Robinson obtained Equation (14), where A = 6-6, A = 6 -6, A° = <5° -S °, and R = KJK1 20 Moreover, it is not necessary to prepare solutions of exact molarity, because n can be evaluated more readily as (6-6 )/(6° -6 ), from the variation of the chemical shift of HA during the titration. When R is near 1, this is approximately a parabolic dependence of A on n. The titration of a mixture of formic acid and 1802-formic acid permitted the evaluation of the lsO IE on acidity from the 13C NMR chemical shifts 6 and S of the carboxyl carbons. In practice, this involved fitting to the three parameters A-, A°, and R. This same equation was used with 31P chemical shifts to evaluate the lsO IE on the acidity of phosphoric acid and alkyl phosphates.21... 

Monoalkyl and dialkyl derivatives are also obtained in these reactions. Alkyl phosphates are used as acid catalysts, lubricants, and intermediates in preparing flameproofing compounds. 

The heat of hydrolysis with water is 74-7 Cals.2 If much water is used the products are orthophosphoric and hydrochloric acids, but when the compound deliquesces in moist air pyrophosphoryl and metaphosphoryl chlorides [q.v.) are formed as intermediate products.3 It is also hydrolysed by hydroxylated organic compounds and is much used for preparing chlorinated derivatives, e.g. C2H5C1 and CH3COCl from C2H5OH and CH3COONa respectively. By this means also alkyl chlorophosphates and alkyl phosphates can be prepared, e.g. —... 

This is a general method for preparing alkyl phosphates. Using a similar procedure, the M-propyl ester may be obtained in 60-65 per cent yields, the sec.-butyl ester in 40-45 per cent yields, and the w-amyl ester in 60-65 per cent yields, from the corresponding alcohols. ... 

Alkyl phosphates are more easily prepared by the addition of phosphorous pentoxide to fatty alcohols or fatty alcohol ethoxylates. 

Barr et al. and Bravo et al. used a different technique for sample preparation and determination of alkyl phosphates in urine the urine was spiked with internal standard and then concentrated to dryness via azeotrope codistillation with acetonitrile. The residue was dissolved in acetonitrile, derivatized and then analyzed using GC-MS. Both studies reported satisfactory validation data with coefficients of variation of <20%. 

Ribonucleoside 2 3 -cyclic phosphate are far more liable toward alkali and acid than are the noncyclic phospho-diesters. Hydrolysis of ribonucleoside 2 3 -cyclic phosphate produces a mixture of 2 - and 3 -phos-phates in approximately equal amoimts. Acid- and alkali-catalyzed alcoholysis of these cyclic phosphates also produces a mixture of the 2 -and 3 -alkyl phosphates, - - and the reactions are apparently reversible. " This behavior is a rather general characteristic of five-mem-bered, cyclic phosphates. [[Six-membered, cyclic phosphates, namely (25), (28), and (28a), are relatively more stable. Phosphodiesterases have been employed for the convenient preparation of specific nucleoside 2 - or 3 -phosphates by selective cleavage of a particular 0-P linkage in nucleoside 2 3 -cyclic phosphates. ... 

Many of the organic contaminants which were found in Lippe river water were also present in the source samples (see Table 3). The sewage effluent sample and the Seseke river showed the best accordance with the compound spectrum of the Lippe river. However, also in the two tributaries from the rural upper reaches of the river, numerous specific contaminants like 9-methylacridine (No. 8), alkyl phosphates (Nos. 31, 32) and chlorinated alkyl phosphates (Nos. 34, 36) appeared. In the effluent of a pharmaceutical plant, only a few Lippe river contaminants like n-alkanes (No. 1), naphthalene (No. 3), TXIB (No. 21) and caffeine (No. 67) were detected (see Table 3). Therein, mainly structural relatives of androstanone like 3p-hydroxy-5p-androstan-17-one, 3a-hydroxy-5p-androstan-17-one and androstan-50-3,17-dione were present. These compounds are probably by-products of the synthesis of hormone preparations. Some polycyclic aromatic compounds, halogenated compounds and terpenoids were not detected in the source samples (see the underlined compounds in Table 3) and probably have another origin. Representative sampling of various input sources have to be carried out to prove the origin of these compounds. Hexachlorobutadiene (No. 38) and bis(chloropropyl)ethers (No. 44) appear exclusively at the lower reaches of the Lippe river (see Table 1), downstream the chemical plants in Marl. They are attributed to inputs of the chlorochemical industry (see section 3.1). Hence, this suggests their input by an industrial point source. 

Preparation procedure. Tri-n-alkyl phosphate ((RO)3P(0)), titanium tetra-aUcyloxide (Ti(OR)4) and potassium alkyloxide (KOR) (R is n-alkyl Et, Pr, Bu) (all Aldrich GmbH) were used as starting reagents. The ROH alcohols were dried over magnesium alkyloxide and distilled before use. All synthesis stages were conducted in dry argon atmosphere. An equimolar mixture of (RO)2P(0)(OH) and Ti(OR)4... 

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