Phosphoric acid esters mixed

Phosphoric acid esters having a low content of arsenic can be obtained by treating with 0.1-10% adsorbents such as activated clay, active carbon, alumina, and silica gel to decrease the arsenic content. Thus, 100 parts lauryl phosphate containing 10.3 ppm As and 2 parts activated clay were mixed at 60-70°C for 2 h and filtered to give lauryl phosphate only containing 0.6 ppm As [28]. 

Table IV gives the Rf values determined under these conditions. Figure 3 shows the chromatograms of the reaction products of the re-esterification of a number of plasticizers. It is obvious that the method is suitable for identifying the alcohol components of all frequently used ester types. Difficulties have been met with phenolic components although they are present primarily in phosphoric acid esters. To identify these, evaporate to dryness a few drops of the reaction mixture of an alkaline saponification and mix this with a bit of the precipitated alkali salt. Add this residue to 10 to 20 drops of chloroform and gradually evaporate it repeat...

A solution of 1 part of a,a -diethyl-4,4 -dihydroxystilbene in 5 parts of pyridine is added drop by drop to the strongly cooled solution of 2 parts of phosphorus-hydroxy chloride in 5 parts of pyridine. The mixture soon solidifies to a crystalline magma. It is allowed to stand in ice for A hour and then for an hour at room temperature. The mass is then poured into an excess of saturated sodium bicarbonate solution. Unconsumed parent material is removed by extraction with ether. The aqueous solution is then mixed with 2 N hydrochloric acid, whereupon the primary phosphoric acid ester of a,a -diethyl-4,4 -dihydroxystilbene of the formula is precipitated in the form of a voluminous white powder. By recrystallization or reprecipitation this ester may be further purified. 

Acetyl fluoride as reactant 24,578 Acid anhydrides, mixed s. Acyl phosphoric acid esters. Carboxylic acid anhydrides, mixed... 

Calcium chloride Mixed phosphoric acid esters... 

Plasticizers are mixed into polymers to increase flexibility and workability. The phosphoric acid esters, i.e., organophosphates, are also remarkable flame retardants, and for this reason they are extensively used in plastics." At present, some 300 plasticizers are manufactured, of which at least 100 are of commercial importance. Most reports on plasticizers known to be present in the indoor environment are either on phthalate esters (phthalates) or on phosphate esters (organophosphates). Their production capacities are high, they may reach from some thousand tons per year (e.g., TCEP) up to some million tons (DEHP) (Table 17.5.2). 

Mixed phosphoric acid esters from dialkyl phosphites (RO)2POH - (RO)2POOR s. 10,107si7 mixed polyfluoroalkyl phosphates with [PhCH2NEt3] Cr as catalyst cf. B.M. Adamov et al., Zh. Obshch. Khim. 58, 2774-80 (1988) dialkyl aryl phosphates from dicyclohexylammonium aroxides s. Purnanand et al.. Tetrahedron Letters 30, 1687-8 (1989). 

Bromocyanoacetamide Mixed phosphoric acid esters and unsym. pyrophosphoric acid esters s. 18,171... 

It is claimed that the physical state of suitable hydrocarbons for alkyl phosphoric acid ester-hydrocarbon antifoam precursor mixtures can range from liquids to waxes and gel-forming hydrocarbons such a petroleum jelly [30, 31]. It is obvious from the description of the mode of action of mixed hydrophobic particle-oil antifoams described in Chapters 4 through 6 that the antifoam entities should be effectively dispersed as liquid drops of a few microns diameter with the particles adhering to the oil-water interface. Incorporation of, say, a wax-alkyl phosphate acid ester mixture by, for example, spraying a molten mixture directly onto a detergent powder (or onto a carrier material such as soda ash) produces macro-drops, which will rapidly freeze to form particles of order of a few hundred microns diameter if the relevant... 

Mixed phosphoric acid esters from trichloroacetiminoesters... 

Mixed phosphorous acid esters s. 12, 310 Mixed phosphoric acid esters from isoureas... 

Pinner cleavage—Halides and mixed phosphoric acid esters s. lA, 605... 

It is however more complicated, esters of phosphorous acid being also formed (c/. p. 308). Iodides are usually prepared by a modification of this method, the ethanol being mixed with red phosphorus, and iodine added. The phosphorus iodide is thus formed in situ, and at once reacts with ethanol to give the corres ponding iodide. 

CP esters are generally prepared as the ammonium salt [9038-38-4] by the reaction of cellulose with phosphoric acid and urea at elevated temperatures (130—150°C). The effects of temperature and urea/H PO /cellulose composition on product analysis have been investigated (33). One of the first commercially feasible dameproofing procedures for cotton fabric, the Ban-Flame process (34,35), was based on this chemistry. It consists of mixing cellulose with a mixture of 50% urea, 18% H PO, and 32% water. It is then pressed to remove excess solution, heated to 150—175°C for 5—30 minutes, and thoroughly washed (36). 

B. 2-Methylcyclopenlane-l,3,5-trione hydrate. A mixture of 200 g. (0.89 mole) of the keto ester prepared above, 910 ml. of water, and 100 ml. of 85% phosphoric acid is healed under reflux for 4 hours and then cooled in an ice-salt bath to —5°. The trione mixed with oxalic acid separates and is collected by filtration and dried under reduced pressure. The dried material is extracted with boiling ether (250-300 ml.) under reflux, and the ethereal extract is separated from the undissolved oxalic acid. The original aqueous filtrate is also extracted with ether in a continuous extractor. The two extracts are combined, and ether is removed by distillation. The crude trione separates as a dark brown solid and is crystallized from ca. 250 ml. of hot water. The once-crystallized, faintly yellow product weighs 95-105 g. (74-82%), m.p. 70-74°. This product is used in the next step without further purification. A better specimen, m.p. 77-78°, which is almost colorless, can be obtained by recrystallization from hot water after treatment with Norit activated carbon. 

The preparation of phosphate esters has been reviewed and full details have appeared of the use of 2-chloromethyl-4-nitrophenyl esters (reported last year) in the synthesis of monoesters and mixed dialkyl esters of phosphoric acid. 

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