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Diethyl- -phosphate

Table 4. Relative Toxicity of Substituted Phenyl Diethyl Phosphates... Table 4. Relative Toxicity of Substituted Phenyl Diethyl Phosphates...
Hydroxy groups on benzene rings can be replaced by NH2 groups if they are first converted to aryl diethyl phosphates. Treatment of these with KNH2 and potassium... [Pg.866]

Reductive removal of oxygen from aromatic rings can also be achieved by reductive cleavage of aryl diethyl phosphate esters. [Pg.440]

A mechanism proposed 87) for the alkaline hydrolysis of tetraethyl pyrophosphate, which is markedly accelerated by HPO e ions, has been substantiated by isotopic labeling 88). The nucleophilic attack by HPOJp on the symmetrical pyrophosphate 131 is considered to lead initially to the unsymmetrical P P1-diethyl pyrophosphate dianion 132 which decomposes spontaneously under the conditions of reaction to give the diethyl phosphate anion and POf 102. The latter reacts with water to form inorganic phosphate and with alcohols suclj as methanol and ethylene glycol to produce alkyl phosphates. [Pg.102]

Presence of hydrogen chloride as impurity causes an uncontrollable exothermic reaction dining preparation of diethyl phosphate from the title compound. [Pg.559]

Diethanol Sulfide Diethanolamine Diethanolethylamine Diethanolmethylamine Diethoxyethylphosphine Oxide Diethoxymethylphosphine Oxide Diethoxyphosphine Oxide Diethyene Disulfide Diethyl Acid Phosphate Diethyl Ethanephosphonate Diethyl Ethylphosphonate Diethyl Hydrogen Phosphate Diethyl Hydrogen Phosphite Diethyl Hydrogen Phosphonate Diethyl Isopropylphosphonate Diethyl Methanephosphonate Diethyl Methylphosphonate Diethyl Phosphate Diethyl Phosphite Diethyl Phosphonate Diethyl Phosphoric Acid Diethyl(2-hydroxyethyl)amine Diethyl(/S-hydroxyethyl)amine Diethylaminoethanol Diethylethanolamine Diethylfosfit... [Pg.650]

In a rare example of the use of phenylselenides as radical precursors in the generation of alkene radical cations by the fragmentation approach, Giese and coworkers generated a thymidine C3/,C4/ radical cation by expulsion of diethyl phosphate. Trapping experiments were conducted with methanol and with allyl alcohol (Scheme 16), when nucleophilic attack was followed by radical cyclization [66]. [Pg.32]

The contrast between the lack of enantioselectivity in Scheme 39 and the moderate to excellent diastereoselectivity seen with alcohol nucleophiles in Schemes 19 and 33 can be attributed to the difference in leaving groups (diphenyl phosphate vs diethyl phosphate) and to the differences in the radical cations themselves, all of which impinge on the rate of equilibration of the contact alkene radical cation/anion pair. [Pg.45]

Cyanohydrin diethyl phosphates 87, easily accessible from propargyl aldehydes or ketones of type 86, reacted with lithium dialkylcuprates or similar reagents via an Sn2 process to give cyanoallenes in moderate to good yields [135]. The transformations 80 —> 81 and 84 —> 85 are only formally also SN2 reactions. Thus, plausible catalytic cycles, which include different short-lived palladium intermediates, have been postulated to explain these nucleophilic substitution reactions [127, 134],... [Pg.370]

Kosolapoff2 has prepared T.E.P.P. by the action of chlorine on a mixture of sodium diethyl phosphate and diethyl phosphorochloridate followed by the addition of an excess of alcohol. [Pg.117]

S Kim, A Chang, YK Ko. Benzotriazol-l-yl diethyl phosphate. A new convenient coupling reagent for the synthesis of amides and peptides. Tetrahedron Lett 26, 1341, 1985. [Pg.231]

The DD-CSA cross-correlated relaxation, namely that between 13C-1H dipole and 31P-CSA, can also be used to determine backbone a and C angles in RNA [65]. The experiment requires oligonucleotides that are 13C-labeled in the sugar moiety. First, 1H-coupled, / - DQ//Q-II CP spectra are measured. DQ and ZQ spectra are obtained by linear combinations of four subspectra recorded for each q-increment. Then, the cross-relaxation rates are calculated from the peak intensity ratios of the doublets in the DQ and ZQ spectra. The observed cross-correlation rates depend on the relative orientations of CH dipoles with respect to the components of the 31P chemical shift tensor. As the components of the 31P chemical shift tensor in RNA are not known, the barium salt of diethyl phosphate was used as a model compound with the principal components values of -76 ppm, -16 ppm and 103 ppm, respectively [106]. Since the measured cross-correlation rates are a function of the angles / and e as well, these angles need to be determined independently using 3/(H, P) and 3/(C, P) coupling constants. [Pg.142]

Certain organophosphorus compounds can be used to melt-stabilize PET. Stabilizers such as 3,5-di-t-butyl-4-hydroxybenzyl diethyl phosphate (Irganox 1222) and triphenylphosphate lead to a reduction in the concentration of terminal carboxyl groups of PET, thus giving improved hydrolytic stability. [Pg.531]

The e.s.r. spectra of y-irradiated diethyl phosphate and its salts have been studied111 and the structures of the phosphonates(89)112 and some nucleoside phosphates113 have been studied from the e.s.r. spectra of the nitroxide spin-labelled compounds. An e.s.r. study of electron transfer in dinucleoside phosphate anions indicates preferen-... [Pg.261]

Diethyl phosphate esters of the sterically congested phenols of calixarenes have been prepared in acceptable yields (>55%) and used in the preparation of meta-cyclophanes [8]. The corresponding reaction using diethyl phosphite, with triethylamine in place of the quaternary ammonium catalyst, results in only partial phosphorylation of the hydroxyl groups. [Pg.110]

The reaction of but-l-en-3-yl diethyl phosphate with diethylamine produces N,N-diethylpent-3-enamide (86%), indicating that a Ji-allyl complex is involved in the carbonylation reaction. No isomerism to the a,p-unsaturated amides was observed. [Pg.379]

N. Nikolaides, 1. Schipor, and B. Ganem 246 CONVERSION OF AMINES TO PHOSPHO ESTERS DECYL DIETHYL PHOSPHATE... [Pg.1]

Decyl diethyl phosphate Phosphoric acid, decyl diethyl ester (9) (20195-16-8)... [Pg.278]

K. Yoshida, Y. Kurono, Y. Mori, K. Ikeda, Esterase-Like Activity of Human Serum Albumin. V. Reaction with 2,4-Dinitrophenyl Diethyl Phosphate , Chem. Pharm. Bull. 1985, 33, 4995-5001. [Pg.96]

Two types of amphiphilic quaternary 3-pyridinium ketoximes (253a, b) with different positioning of the hydrophobic alkyl chain have been synthesized and tested as hydrolytic micellar catalysts. A considerable positive deviation from the expected first-order curve was observed in the absorbance vs time plot when p-nitrophenyl diphenyl phosphate (252 R = Ph) and p-nitrophenyl diethyl phosphate... [Pg.80]

Soil. Cleavage of the molecule yields diethyl phosphate, monoethyl phosphate, and phosphoric acid (Hartley and Kidd, 1987). [Pg.1010]

Diethyl phosphate, see Sulfotepp Diethyl phosphoric acid, see Diazinon. Parathion Diethyl phosphorothioate, see Diazinon 0,0-Diethyl phosphorothioic acid, see Chlorpyrifos, Diazinon. Malathion, Parathion Diethyl sulfide, see Chlorpyrifos Diethyl thiomalate, see Malathion Diethylthiomaleate, see Malathion Diethylthiophosphoric acid, see Diazinon. Parathion Diethyl-0-thiophosphoric acid, see Parathion... [Pg.1526]

A regio-, diastereo- and enantioselective synthesis of amino acids was reported by Takemoto and coworkers. The glycine equivalent ethyl diphenylimino glycinate was used as pronucleophile (Scheme 9.14), while the Hgand was a bidentate chiral phosphite, and 3-arylaUyl diethyl phosphates were employed as allylic substrates [39, 46]. [Pg.225]

A few other hydroxylamine derivatives were tested with cinnamyl diethyl phosphate as substrate (Scheme 9.30, Ar= Ph) and Cs(OH)-H20 as base [39]. The addition of a base was necessary in the case of N,0-dibenzoylhydroxylainine, whereas the reaction with N, O-dibenzylhydroxylamine proceeded without base. The corresponding amide N-benzoylbenzylamine did not undergo the reaction. [Pg.239]

Sodium telluride and sodinm 0,0-diethyl phosphorotellurolate, prepared respectively by the Te/NaBH4DMF method and by the reaction of elemental tellurium with NaH and 0,0-diethyl phosphate in ethanol, react with arenediazonium fluoroborates, giving good yields of diaryl tellurides. ... [Pg.20]

In the initial screening of various Cinchona alkaloids, the addition of diethyl phosphate 41 to IV-Boc imine 40 in toluene revealed the key role of the free hydroxyl group of the catalyst. Replacing the C(9)-OH group with esters or amides only results in poor selectivity. Quinine (Q) was identified as an ideal catalyst. A mechanistic proposal for the role of quinine is presented. Hydrogen-bonding by the free C(9)-hydroxyl group and quinuclidine base activation of the phosphonate into a nucleophilic phosphite species are key to the reactivity of this transformation (Scheme 9). [Pg.154]

In the electrochemical reduction of aryl diethyl phosphates, the initial one-electron addition is to the aryl ring and this is concerted with expulsion of the diethyl phosphate anion leaving an aryl radical. Further electron addition and protonation leads to the reaction product in 43-73 % yields. Examples of this electro-... [Pg.163]

Enehydroxylamine 0-derivatives 149 and 151, prepared from the reactions of A-alkyl-3-(hydroxyamino)cyclohex-2-enone (148, R = H) and iV-alkyl-3-(hydroxyamino)-5,5-dimethylcyclohex-2-enone (148, R = Me) with MsCl (equation 41) and Mc2NC(S)Cl (equation 42), respectively, in the presence of base rearrange spontaneously providing the corresponding [3,3]-sigmatropic rearranged products 150 and 152 in moderate to excellent yield . However, the diethyl phosphate 153 (equation 43) and the O-benzoyl hydroxylamine 154 rearrange under reflux in toluene (equation 44). [Pg.374]


See other pages where Diethyl- -phosphate is mentioned: [Pg.330]    [Pg.772]    [Pg.670]    [Pg.296]    [Pg.36]    [Pg.100]    [Pg.104]    [Pg.250]    [Pg.130]    [Pg.24]    [Pg.36]    [Pg.373]    [Pg.93]    [Pg.276]    [Pg.580]    [Pg.87]    [Pg.334]    [Pg.163]   
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See also in sourсe #XX -- [ Pg.428 ]

See also in sourсe #XX -- [ Pg.428 ]

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See also in sourсe #XX -- [ Pg.377 ]

See also in sourсe #XX -- [ Pg.272 ]




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