Phosphoric monoesters, addition

Gold-catalysed Markovnikov addition of phosphoric monoesters R C=CP(0) (OEt)(OH) to terminal alkynes R C=CH has been found to generate enol esters R C=CP(0)(0Et)0C(R )=CH2, which then undergo gold-catalysed cyclization to produce 4,6-disubstituted phosphorus 2-pyrones in one pot. ... 

There are some means for synthesis of defined primary or secondary esters. Monoester salts of phosphoric acid, for instance, are prepared by addition of alcohol or ethoxylated alcohol, alkali fluoride, and pyrophosphoryl chloride (C12P0)20 in a molar ratio of 0.9-1.5 0.05-1 1.0 at -50 to +10°C and hydrolysis of the Cl-containing intermediates with base. Thus, 32.3 g (C12P0)20 was treated at -50°C with 23.9 g lauryl alcohol in the presence of 0.7 g KF and the mixture was slowly warmed to room temperature and hydrolyzed with H20 and 40% NaOH to give 83% sodium monolauryl phosphate. The monoester salts showed comparable or better washing and foaming efficiency than a commercial product [12]. 

Many bacterial polysaccharides contain phosphoric ester groups. There is a limited number of examples of monoesters. More common are phosphoric diesters, connecting an amino alcohol or an alditol to the polysaccharide chain. Another possibility is that oligosaccharide or oligosaccharide-alditol repeating units are connected to a polymer by phosphoric diester linkages. In addition to the intracellular teichoic acids, several bacteria, for example, different types of Streptococcus pneumoniae, elaborate extracellular polymers of this type. These polymers are generally discussed in connection with the bacterial polysaccharides. 

Acid-Catalyzed Synthesis. - 3.2.1 The Fundamentals. Homogeneous acid catalysts, such as sulfuric acid, phosphoric acid, hydrochloridric acid, organo sulfonic acids and others, can be used to catalyze the transesterification of TGs and the esterification of FFAs to produce biodiesel type monoesters. Nevertheless, because the acid-catalyzed transesterification is about 3 orders of magnitude slower than the alkali-catalyzed reaction for comparable amounts of catalyst, base catalysts have received the most attention in both the academic and industrial sectors. In addition, the corrosiveness of strong liquid acids and... 

In addition to the hydrolysis of monoesters of phosphoric acid, the hydrolysis of diesters of phosphoric acid is also susceptible to metal ion catalysis, in particular by multivalent cations such as barium, stannous, and cupric ions. The diesters which undergo metal ion-catalyzed hydrolyses include open-chain diesters and cyclic diesters containing both five- and six-membered rings (54). 

Monoalkyl phosphate and phosphate esters are special types of phosphoms-contain-ing anionic surfactants that are of great industrial importance. They are used for flameproofing, as antistatic for textiles, for foam inhibition, as an extreme pressure (EP) lubricant additive, as a surfactant component for alkaline, and as acid cleaners and for special cosmetic preparations (5). The commercially available phosphate ester products are complex mixtures of monoester and diester, free phosphoric acid, and free nonionic. 

Alkyl phosphates, also coco based, are formed by the reaction of fatty alcohol with phosphorous pentoxide. The product is a mixture of monoesters and diesters. Its sodium salt (MAP) is reportedly mild and is used in facial wash, such as Kao s Biore. Other uses are as antistatics in textile auxiliaries, corrosion inhibitors, surfactant additives for extreme pressure (EP) lubricants, and surfactant components in alkali and acid cleaners. Coco-based alkyl polyglycosides (APG) have been successfully produced and marketed by Henkel in the United States. The alkyl polyglycoside fuUy satisfies the demand for a mild surfactant and is completely biodegradable. 

Compounds with phosphorus as the key element that have been investigated for extreme-pressure additive activity add up to an impressively long list. But only a few of them have turned out to be of practical utility and these are predominantly esters of phosphoric acid or derivatives of thiophosphoric acid. In this section we shall be concerned only with those compounds in which phosphorus in combination with oxygen constitutes the key structure dithiophosphates and related derivatives are discussed in Section 11.2.6. The four main types of phosphorus oxyacid esters treated in the present section are shown in Table 11-12. Phosphoric and phosphorous acids are trifunctional hence there are three or-ganophosphorus structures to be considered the neutral triester, the monoacidic diester and the diacidic monoester. 

Addition of hypophosphorous acid, PH(OH)2 to Schiff bases, yielding (l-aminoalkyl)phosphorous acids, can also be effected by mixing the three reactants.129 Further, Schiff bases have also been added to dialkyl thiophos-phites,130 phosphonous monoesters,130 secondary phosphine oxides,117 and metal derivatives of secondary phosphines 131 these phosphides, however, give well-defined products only after hydrolytic working up to phosphine oxides. 

Monoester of sulfuric acid and 3-chloro-1,2-propanediol (as a result of NaHS04 addition to epichlorohydrin) can also be used for the preparation of sulphatobetaine through the reaction with tertiary amines. The same reaction of the monoester of phosphoric acid gives rise to... 

TOBACCO [NicoTiANA TABACUM L.) Fractions M-Ia and M-Ib from acid phosphatase of tobacco cells did not hydrolyse phosphate monoesters except para-nitrophenyl phosphate, but hydrolysed phosphoric anhydrides (inorganic pyrophosphate, thiamine pyrophosphate, nucleoside di- and triphosphates). In addition, both fractions hydrolysed bis-para-nitrophenyl phosphate. Fraction M-II, a non-specific acid phosphatase, had broad substrate specificity it hydrolysed pyrophosphate, thiamine pyrophosphate, uridine diphosphate, adenosine triphosphate, uridine triphosphate, and cytidine triphosphate, at rates similar to para-nitrophenyl phosphate (Ninomiya et al., 1977). 

Without additional reagents Phosphorous and phosphinic acid monoesters... 

There are at least three possible biochemical mechanisms for the activation of carboxyl groups a phosphoric acid anhydride, an adenylate, or a thiolester may be formed. Since radioactivity was not incorporated from either ATP or [2- H adenin]-ATP, into the activated intermediate, a coenz3nne A ester was likely to be present.. Indeed, the activated intermediate was shown to contain coenzyme A and OSB (II) in the ratio 1 1. Thus, hydrolysis of the activated intermediate and quantitative determination of OSB (II) and coenz3 e A by HPLC showed that the activated OSB (II) was a monoester of coenzyme A. In addition, quantitative determination of OSB (II) by its known specific radioactivity and of coenzyme A by means of a coupled enzyme assay gave an identical result. Finally, when the -succinylbenzoate coenzyme A ligase preparation was incubated with C-OSB and H-coenzyme A, the ratio of... 

DNA is not easily hydrolyzed to nucleotides by acid or base. This can now be explained as due to the impossibility of forming cyclic triesters before hydrolysis, since there is no hydroxyl group on C2. Likewise C2 is not available for internucleoside links in DNA. The results of titrating DNA can be explained by the dissociation of 1 secondary phosphoryl group for every 10 to 20 nucleotides in addition to the amino and — NH—CO— dissociations of the purines and pyrimidines. Thus there is 1 triester and 1 monoester of phosphoric acid in 10 to 20 diesters. Branching is at a minimum. Enzymatic hydrolysis results in nucleoside-5 -phosphates. Supported by physical data, the concept of the DNA molecule is that of a long, slightly branched chain structure of C3 nucleotides linked to each other by a phosphoester bond at Cb. ... 

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