Diethyl -phosphonate

NH4OH, MeOH. These conditions result in cleavage of only one ethyl group of a diethyl phosphonate. Selective monodeprotection of a number of alkyl-protected phosphates is fairly general for cases where cleavage occurs by the release of phosphate or phosphonate anions. 

Scheme 5.1-43 Three-component reaction of benzaldehyde, aniline, and diethyl phosphonate in ionic liquids, catalyzed by lanthanide triflates and indium(lll) chloride.

The rigid, planar pyridine analog 111 was isolated in low yield by first hydrolyzing the known (67) pyridine diethyl phosphonate 109 to the corresponding free acid 110 followed by permanganate oxidation (2). An alternative synthesis of 111 has recently been reported (68). Alkylation of pyridine-2-carboxylate -oxide with dimethylsulfate and subsequent reaction with the sodium salt of diethyl phosphite gave the triester 112, which was readily converted to 111. 

The heats of ionisation and neutralisation of amino and hydroxylic bis and tris phosphonic acids have been investigated.253 Calorimetry in combination with u.v. and n.m.r. spectroscopy uas used to study the adducts of fluoroalkyl carboxylic acids with diethyl phosphonate.254 The heats of formation of the t-butoxytriphenylphosphoranyl radical uas consistent with the phosphonium structure (92).255 There has been a thermal analysis of the adducts of phosphonic and phosphoric acids with... 

Diethyl arylphosphonates were synthesized by reactions of diethyl phosphonate with aryl iodides or bromides containing electron-donor or electron-acceptor substituents in the aromatic ring in aqueous MeCN or neat H2O in the presence of Pd complexes with water-soluble ligands.34 For example, MeCN/H20 (1 mL), PhBr (8.2 mmol), and Ph2P(C6H4S03Na-m) (approximately 0.4 mmol) were successively... 

The presence of trialkyl phosphite 198 in the above mentioned reduction of the gem-dibromocyclopropanes 150 with dialkyl phosphonate and triethylamine alters the reaction course. Dialkyl cyclopropanephosphonates 199 are produced via reductive phosphonation [104]. Trialkyl phosphite participates in the carbon-phosphorous bond formation. It is supported by the exclusive formation of diisopropyl cyclopropylphosphonate in the phosphonation reaction with diethyl phosphonate and triisopropyl phosphite. (Scheme 74)... 

Vanadium compounds in a low oxidation state are known to be effective for inducing one-electron reduction. The highly stereoselective monodebromination of gem-dibromocyclopropanes proceeds with the help of a low-valent vanadium species generated from vanadium(III) chloride and zinc in dimethoxyethane in cooperation with diethyl phosphonate or triethyl phosphite... 

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... 

Walsh, E.N., Conversion of tertiary phosphites to secondary phosphonates. Diethyl phosphonate, /. Am. Chem. Soc., 81, 3023, 1959. 

Scheme 2 shows preparation of the biftinctional fiber. PPPE-c and PPPE-f grafted with CMS and ST were functionalized by the reported method.6 Here, an example of functionalization procedures is described. The precursory fibers (PPPE-f grafted with CMS and ST, 2 g) and triethyl phosphite (60 ml) were taken into a three-necked flask (200 ml) equipped with a Liebig condenser. After the mixture in the flask was heated for 48 h at 100 °C, the resulting phosphorylated PPPE-f was washed with acetone, aceton-water mixture and water, and dried in vacuum oven at 40 °C. In order to introduce sulfonic acid groups, the phosphorylated PPPE-f was treated with a 30 mL of 1,2-dichloroethane solution of chlorosulfonic acid (10 wt %) for 2 h at room temperature. Finally, diethyl phosphonate groups on the fibers were hydrolyzed with 12 M hydrochloric acid under refluxed... 

We found that diethyl hydrogen phosphite (almost certainly as the tautomeric diethyl phosphonate (IV)), reacted very nadily with chlorine to give the required diethyl phosphoro-chloridate (V) in 87 per cent yield ... 

The hydrophosphorylation of internal alkynes is somewhat slow. For instance, the reaction of 4-octyne with diethyl phosphonate resulted in 82% yield only after heating for 65 h. Only c/s-isomer was observed in NMR spectroscopy. 

More than two decades age, Hirao and coworkers briefly described a rather unsuccessful attempt of hydrophosphorylation of a diene isoprene underwent Pd-catalyzed addition of diethyl phosphonate forming diethyl 3-methyl-2-buten-l-ylphosphonate in only 10% yield even under forcing conditions (150 °C, 20 h) [29]. By using the exceptionally reactive five-mem-... 

Among the early attempts of amination of lithium and copper enolates were those which involved formation of a-A-(Boc)- or A-(Alloc)amino-substituted carboxylic esters, A-acyloxazolidinones and diethyl phosphonates (Scheme 33) ° . a-Lithum or a-copper derivatives of these enolates were aminated using A-lithium derivatives of A-Alloc O-(mesitylenesulfonyl)hydroxylamine 3j, NHBocOTos 31 and NHAllocOTos 3m. 

Sugars containing a carbon-phosphorus bond have been prepared by application of the Michaelis-Arbuzov reaction to bromodeoxy sugars. Thus, the reaction of 5-bromo-5-deoxy-l,2-0-isopropylidene-3-O-methyl-a-D-xylofuranose (131) with triethyl phosphite yields the corresponding diethyl phosphonate (132) compound 132 was employed for the synthesis of a sugar derivative having phosphorus as... 

Commercial diethyl phosphonate, (C2H50)2P(0)H, formerly known as diethyl phosphite, from Aldrich Chemical Co., Inc., was used without further purification. 

Some white foam forms as the diethyl phosphonate is added. Because water in the ammonia consumes some of the sodium, not quite all the diethyl phosphonate is required to reach the endpoint. Excess diethyl phosphonate is deleterious. 

Diethyl phosphonate Phosphonic acid, diethyl ester (8,9) (762-04-9)... 

Diethyl phosphonate, 58, 134, 135, 138 Diethyl propionylsuccinate, 58, 80 82, 85 Diethyl succinate, 57, 1 Diethyl succinates, acylated, 58, 81 Diethyl sulfate, 56, 48 DIETHYL fnzHS-4-TRIMETHYLSILYL-OXY-4-CYCLOHEXENE-1,2-DICAR-BOXYLATE, 58, 163, 164, 167... 

Statine was identified as a starting material that contains predetermined stereochemistry at the C4 and C5 atoms. Nakano and co-workers155 56 degraded statine to an aldehyde, (45,5R)-4-alkyl-3-benzyloxycarbonyl-5-formyl-2,2-dimethyloxazolidine, which is an intermediate of the method described in Scheme 17. Then, the elongation of this aldehyde was carried out by the Wadsworth-Emmons reaction with diethyl phosphonate. 

The aldehydes 3 were synthesized either by Vilsmeyer formyladon of 2 or by reaction of 4-fluorobenzaldehyde with a secondary amine (20). The stilbenes 4 were formed from the corresponding 4-dialkylamino-benzaldehydes either by the Homer-Emmons reaction with 4-nitrobenzyl-(diethyl)phosphonate (prepared by the Arbuzov reaction of a-bromo-4-nitrotoluene) or with 4-methylsulfonylbenzyl(diethyl)phosphonate (prepared in three steps from 4-methylthiobenzylaicohol) (21). A few nitrostilbene compounds were synthesized by heating aldehyde 3 with 4-nitrophenylacetic acid in the presence of piperidine. 

In a study by Hansch, five mete-substituted diethyl phosphonate esters (12.14) showed cholinesterase inhibition in fruit flies. Correlations between cr-values, ),-values, and both parameters together were explored. The relevant data are included in Table 12.5. 

The bromide 3 was prepared by Stuhr-Hansen et al. [10] from the thiol 20 upon treatment with 2-chloro-2-methylpropane in the presence of catalytic amount of aluminum chloride (Scheme 10.6). Lithiation followed by reaction with DMF afforded the aldehyde 7. This aldehyde can be converted to the diethyl phosphonate 8 in three high-yielding steps, via alcohol (21) and bromide (22) intermediates. 

Finally, ortho- 2,2-dibromovinyl)-aniline or -acetanilide can successfully be applied in a sequential cyclizing amination-cross coupling reaction with diethyl phosphonate to furnish the indolyl phosphonic ester 136 or the N-acetyl 2-aryl indole 137 as recently shown by Bisseret and coworkers [ 105] (Scheme 50). This sequence can be also performed with corresponding phenol derivatives furnishing benzofurans. For the N-acetyl 2-aryl indole 137 it can be shown that the Suzuki coupling occurs prior to the intramolecular animation as a consequence of the gradual difference in reactivity between trans-and czs-carbon-bromine bonds. 

Isatin-3-A/TV-di methylhydrazone when reacted with diethyl phosphonate, furnishes i sati n-A -ethyl-N,N-d methyl hydrazonium ethyl phosphonate374. 

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