Reactions of Phosphoric Acid Derivatives

HMPT to the phosphonic amide derivative (35). The blue colour produced on pulse radiolysis of HMPT, initially thought to be due to solvated electrons. 

Further studies on the behaviour of aliphatic amides in refluxing HMPT suggest that the initial intermediate is the nitrilium cation (36), whose sub- 

Of more practical interest is the observation that amides such as (39) are converted into alkylpyridines (40) under these conditions, since the generality 

The nature of the products of oxidation of cyclophosphamide with Fenton s reagent has been further investigated and it now appears that the crystalline isolable product is the dimer peroxide (41). Both (41) and the hydroperoxide 

Alkylation of thiophosphate dianion (43 R = HO) with diazomethane gives both S- and 0-methylation in the ratio of 4 1 the analogous phos-phonothioate (43 R = alkyl) gives a similar ratio. In its reaction with 

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Reactions of Phosphoric Acid Derivatives.— Interest in HMPT both as a solvent and as a reactant continues. In this solvent / -unsaturated carboxylic acids are reduced by lithium to mixtures of the saturated analogues and synunetrically substituted adipic acids addition of lithium acetate gives reasonable yields of substituted glutaric acids, probably by initial metallation by lithium diethylamide (Scheme 2). Butyl-lithium, however, cleaves... 

Reactions of Phosphoric Acid Derivatives.- Polar substituent effects in... 

REACTION OF PHOSPHORIC ACID DERIVATIVES WITH ELECTROPHILES... 

In this chapter, mainly the ROP of cyclic P-containing monomers is discussed. The synthesis of P-containing polymers by the polyaddition is discussed only for the reaction of phosphoric acid derivatives with diepoxides. 

Reactions of Phosphoric Acid and its Derivatives.—Theoretical studies on the conformational properties of cyclic and acyclic phosphate esters, including calculations of angle and torsional strain,66 and on the reactivity of monomeric metaphosphates,67 have appeared. 

Reactions of Phosphoric Acids and Their Derivatives. - Numerous investigations of phosphate ester hydrolysis continue to be reported. The hydrolysis between 1.5 < pH < 4 of five- and six-membered cyclic phosphoramides (71) has been followed by UV and NMR spectroscopy. Small differences in hydrolysis reactivity for n = 5 and n = 6 constitutes evidence for syn lone pair catalysis. The product ratios from the hydrolysis shows that in the five-membered rings the main product is the one produced by endocyclic cleavage meanwhile, in the six- membered cyclic phosphoramide the kinetic product is the one produced by exocyclic cleavage. The syn orientation of two electron pairs on nitrogen stabilizes the transition state of water approach to the phosphoramides by ca. 3 kcal/moN when compared to the orthogonal attack. (Scheme 12). ... 

Reactions of Phosphoric Acids and their Derivatives.- Addition of alcohols (ROH) to diethyl [2,2-difluoro-l-(trifluoromethyl)vinyl] phosphate yields the ether esters (64). Other fluorovinyl phosphates (65 R = F or CF, R = hexyl, cyclohexyl, or Ph) are cleaved by LiAlH /CuBr or by LiAlH /Br2 in THF at -78° to give the ketones (66) the same esters are also cleaved by... 

Reactions of Phosphoric Acids and their Derivatives. - The rearrangement of [(trimethylsilyl)methyl] phosphates to their ethyldimethylsilyl isomers is already known the mechanism of the process has now been examined in more detail and is thought to involve attack by phosphoryl oxygen at the silicon atom with migration of an alkyl group as indicated in Scheme 2. Diphenyl... 

The published experimental data until quite recently supported the belief that for reaction to occur, R could not be tertiary. Thus, Arbuzov and Azanovskaya (21) found that esters of phosphorous acid derived from tetramethylethylene glycol and a primary alcohol interact with an alkyl halide only at the less substituted carbon atom. 

The reactions of phosphorous acid are paralleled still further by the additions of hypophosphorus acid to azomethines in practice, mixtures of amines and carbonyl reactants may be employed ", but the drawbacks to the procedure found for the synthesis of aminoalkylphosphonic acids may well apply here also. In a valuable publication, Dingwall and coworkers described the syntheses of (aminoalkyl)phosphinic acid analogues of many of the naturally occurring aminocarboxylic acids by the simple treatment of the benzyhydrylimine derivatives of the necessary amines with hypophosphorous acid, formed in situ when diphenylmethylammonium hypophosphite is treated with an appropriate aldehyde this step is followed by removal of the A -protection with 48% aqueous HBr, with 18% aqueous HCl or with trifluoroacetic acid in boiling methoxybenzene any second amino group was protected as the phthalimido derivative. 

Nonspecific Phosphoesteroses. These enzymes cleave a variety of phosphoric acid derivatives, even synthetic substrates and lecithins (diesters of phosphoric acid with glycerol and choline). Such enzymes occur among other places in snake venom, and in the intestinal mucosa. Snake venom phosphatases specifically split 3 -phos-phate bonds, giving rise to 5 -monophosphates, whereas chemical hydrolysis yields a mixture of the 2 - and 3 -monophosphates. Free 3 -phosphate groups (the monoesters) are inhibitory in the enzymic reaction. 

In this year, a subsection concerning use of chiral phosphoric acids as catalysts in various chemical reactions, introduced in 2009 for the first time, has been maintained and expanded with new categories due to further, rapid progress in this area. In the subsection reactions of phosphoric acids and their derivatives, total syntheses of valuable, biologically active compounds have been presented in the literature of the review period, among these were... 

Reactions. Heating an aqueous solution of malonic acid above 70°C results in its decomposition to acetic acid and carbon dioxide. Malonic acid is a useful tool for synthesizing a-unsaturated carboxyUc acids because of its abiUty to undergo decarboxylation and condensation with aldehydes or ketones at the methylene group. Cinnamic acids are formed from the reaction of malonic acid and benzaldehyde derivatives (1). If aUphatic aldehydes are used acryhc acids result (2). Similarly this facile decarboxylation combined with the condensation with an activated double bond yields a-substituted acetic acid derivatives. For example, 4-thiazohdine acetic acids (2) are readily prepared from 2,5-dihydro-l,3-thiazoles (3). A further feature of malonic acid is that it does not form an anhydride when heated with phosphorous pentoxide [1314-56-3] but rather carbon suboxide [504-64-3] [0=C=C=0], a toxic gas that reacts with water to reform malonic acid. 

Condensed phosphates are indirectly manufactured derivatives of phosphorous acids, having less water than orthophosphoric acid (two molecules of phosphoric can be written P205 3H20, which indicates the source of the condensation reaction). Condensed phosphates are typically available in either crystalline or glassy forms. 

C. Reactions of Phosphoric and Phosphinic Acid Derivatives.—The optically active phosphinate ester (90) has been shown to react with benzyl Grignard reagents or lithium anilide with inversion of configuration. Oxidation of... 

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