Aryl diphenyl phosphates

A new one-pot method has been developed by Kraszewski for the synthesis of aryl nucleoside phosphate (3a-p) and phosphorothioate (4a-p) diesters. This method, based on H-phosphonate chemistry, employed diphenyl phosphoroch-loridate and a series of phenols. Depending on the substituents present on the phenols, oxidation conditions were optimized to avoid competing hydrolysis. A versatile procedure that permits easy access to H-phosphonoselenoate monoesters (5) has been developed by Stawinski. These monoesters, obtained by selenisation of a phosphinate using triphenylphosphine selenide in combination with trimethylsilyl chloride, reacted with a suitable nucleoside in pyridine/acetonitrile in the presence of diphenyl phosphorochloridate to yield... 

Pyrolysis of 1 mol of DOP yielded 0.97 mol of 2-ethylhexene-l and 0.78 mol of 2-ethylhexanol. Pyrolysis of 1 mol of DOS yielded two mols of 2-ethylhexene-l. This seems to suggest that alcohol is produced as a side effect of anhydride formation because no alcohol was formed from DOS which does not form anhydride. Triaiyl phosphates have high boihng temperatures and are thermally stable but aryl alkyl phosphates are not. The 2-ethylhexyl diphenyl phosphate undergoes decomposition at 170°C ... 

Isodecyl diphenyl phosphate Alkyl aryl phosphate... 

Mixed alkyl aryl esters may be obtained by reacting phosphorochloridates with sodium derivatives of phenols or alcohols (5.297, 5.298). Octyl diphenyl phosphate is obtained commercially by reaction (5.298), the starting material having been obtained from octyl alcohol and phosphoryl chloride by a reaction of type (5.295). 

Fyrolflex BDP from Akzo Nobel Chemicals has been shown to exhibit higher thermal properties and hydrolytic stability than other aryl phosphates, and to provide similar or better fire retardant performance than RDP. It is a bisphenol A bis(diphenyl phosphate) compound that provides good physical properties in formulations based on PC/ABS, HIPS and polyphenylene oxide/HIPS blends. Upon thermal decomposition of the flame-retarded polymers, phosphorus tends to accumulate in the solid residue, a result which indicates that the primary FR action of BDP is most likely to be in the condensed phase. 

The Friedel Crafts amidoalkylation of indoles (119) with N-Ts substituted aryl aldimines (120) has been developed by Shen et al. utilising diphenyl phosphates (121) as organocatalysts to provide the 3-substituted indoles (122) in high yields (Scheme 30). ... 

The superscripts in the methods column denote the following isotopicaUy labeled nucleotide was made by this procedure nucleotide isolated as the 5 -alkyl or 5 -aryl ester only nucleotide isolated as the 2, 3 -0-isopropylidene acetal only nucleotide isolated as the 2, 3 -0-isopropylidene, 5 -alkyl or 5 -aryl ester derivative only nucleotide isolated as the 2, 3 -di-0-benzoyl, 5 -aryl ester only method involves initial formation of a pyrophosphate derivative by reaction of diphenyl phosphorochloridate with hydrobenzoin cyclic phosphate. 

The addition of hydrogenphosphonates to chloroketones, and also to other mono halo-genated carbonyl compounds, is aided by the presence of AI2O3, yields of 78-96% being achievable. However, reactions between dialkyl or diphenyl hydrogenphosphonates and chloroacetone " ", 5 m-dichloroacetone or a ym-dichloroacetone " do occur in the absence of a catalyst when mixtures of reactants are heated to 100-120 °C the products are the phosphonates 173 (R = H or Cl). Aryl trichloromethyl ketones are mon-odechlorinated by the action of trialkyl phosphites or dialkyl hydrogenphosphonates and both further dechlorination and the formation of phosphate esters have been... 

The mode of addition of hydrogenphosphonates to fluorinated ketones can also be complex. The addition of dialkyl, diphenyl or bis(trimethylsilyl) hydrogenphosphonates to methyl trifluoromethyl ketones occurs in the expected manner, but this contrasts with the behaviour of aryl perfluoralkyl ketones in the presence of triethylamine at room temperature, when the products, obtained even under such mild conditions, are phosphate esters (reaction 6), a situation which represents lack of stability of the hydroxyphospho-nate rather than novelty of the reaction under identical conditions, the corresponding alkyl aryl ketones fail to react. The same reaction with mixed-halogen ketones is still more involved, and the nature of the products depends on the reaction conditions if these are of a mild nature, and with catalysis by triethylamine or pyridine (depending on the particular ketone), the product is the expected (hydroxyalkyl)phosphonate 177, whereas with... 

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