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Phosphorus chlorides esters

Phosphor-athcr, m. phosphoric ether (ester of phosphoric acid, specif, ethyl phosphate), -basis, phosphorus base, -bestimmung, /. determination of phosphorus, -blei, n. lead phosphide Min.) pyromorphite. -bombe, f. phosphorus bomb. -brandgranate, /. phosphorus incendiary shell, -brei, m. phosphorus paste, -bromid, n. phosphorus bromide, specif, phosphorus pentabromide, phos-phorus(V) bromide, -bromijr, n. phosphorus tribromide, phosphorus(III) bromide, -bronze, /. phosphor bronze, -calcium, n. calcium phosphide, -chlorid, n. phosphorus chloride, specif, phosphorus pcntachloride, phosphorus(V) chloride, -chloriir, n. phosphorous chloride (phosphorus trichloride, phosphorus(III) chloride), -dampf, tn. phosphorus vapor or fume, -eisen, n. ferrophos-phorus iron phosphide, -eisensinter, m. diadochite. [Pg.339]

Plasticizers include the esters of a few aliphatic and aromatic mono and dicarboxylic acids, aliphatic and aromatic phosphorus acid esters, ethers, alcohols, ketones, amines, amides, and non-polar and chlorinated hydrocarbons. These additives are used in various mixtures. For their separation and qualitative detection, thin-layer chromatography (TLC) is preferred. Usually Kieselgur plates, 0.25 mm thick, activated at 110°C for 30 min, in the saturated vapor are used. Methylene chloride and mixtures of diisopropyl ether/petether at temperatures between 40 to 60°C have been successfully used as the mobile phase. Refer to Table 1. [Pg.98]

The next area which we investigated involves a reaction that is really a variation of the condensation reaction of tris (2-chloroethyl) phosphate. If the chlorine-containing group is on one molecule, and the second molecule is a chlorine-free phosphorus ester, the condensation reaction can be conducted to release and alkyl chloride and to form a new phosphorus-containing ester. This... [Pg.262]

Dietsche, W., Reaction of trivalent phosphorus chlorides with ortho esters and their thio analogs. Preparation of C-phosphorylated formaldehyde acetals, Liebigs Ann. Chem., 712, 21, 1968. [Pg.244]

Optically active phosphorus(iii) acid esters PhR P (OR ) have recently been prepared for the first time by the reaction of a chiral phosphorus chloride and an alcohol or thiol in the presence of an optically active amine, in this case (-)-NN-dimethyl-(l-phenylethyl)amine. (See also Refs. 449 and 450). A kinetic investigation shows that phosphorous acid and chloral react to give 2,2,2-trichloro-l-hydroxyethyl phosphonate at a much lower rate than the corresponding reaction with dimethyl hydrogen phosphite. Phosphorus trichloride and dialkyl phosphites (R0)2P(0)H have been shown to react at low temperature in the presence of pyridine, producing tris(dialkoxyphosphoryl)phosphines [(RO)2P(0)]3P. ... [Pg.310]

Hydroxy-l,2,4-thiadiazoles readily form esters with phosphoric acid and its various analogs. Because of the pesticidal properties of these organo-phosphorus compounds, and their reported relatively low toxicity to warmblooded animals, a large volume of preparative work has been undertaken. The patent literature exemplifies almost the full range of possible phosphoric and phosphonic acid derivatives, and their thio analogs. For their production, a hydroxy-1,2,4-thiadiazole is condensed with the phosphoro- or phosphono-chloridic ester (426 or 429), in the presence of a base.332-336 Alternatively, a halogeno-1,2,4-thiadiazole is allowed to react with the appropriate free acid (424 or 427).337-341 The use of mercapto-l,2,4-thiadiazoles, or of the... [Pg.370]

Mixtures of isomeric 2- or 3-chloroalkyl phosphorus(III) esters (54, major isomer) 55, (minor isomer) are obtained when the cyclic phosphorus(III) chlorides 52 (X, Y = O, S or N-alkyl) react with oxiranes or oxetanes 53. The isomers 55 do not isomerize when heated. [Pg.155]

In outline, the reaction between a phosphorus(III) chloride 462 and an a,)5-unsaturated carboxylic acid 463 might be formulated in a way (Scheme 44) similar to that between the same acids and a phosphorus(III) ester (Scheme 41) a linear dipolar intermediate adduct 464a leads to, or is in equilibrium with, a cyclic chlorophosphonium salt 464b, which, in turn, might be in equilibrium with a pentacoordinate (phosphorane) structure in its tau-... [Pg.235]

Very few reports have been concerned with phosphorus chlorides of the types (RO)2PCl or ROPCI2. For the former (R = Et), the product from propenoic acid consists of the linear ester 465 (R = OR, R = Et R = R" = although readily transformed, when heated comparatively gently, into the corresponding 2-ethoxy-2-oxo-l,2-oxaphospholan-5-one (466), and that from 2-methylpropenoic acid consisted of the corresponding 4-methyl derivative 466 (R" = However, a detailed study of the reaction between (EtO)2PCl... [Pg.236]

The reaction between tris(trimethylsilyl) phosphite and a perfluoroacyl chloride proceeds without any apparent difficulty to give the predicted phosphonate diester 489 [R = Me3Si, R = CF3 or (CF3)2CH] but the use of longer chain polyfluorinated acyl halides or other heavily halogenated acyl chlorides leads to complications with such substrates, the initially formed acylphosphonate reacts with more phosphorus(III) ester to give the (Z)-enol phosphate 490 (Scheme 47). The halides, XCH2COX (X = Cl or Br) afford only the esters 491 (X = H). ... [Pg.241]

A (l-oxoalkyl)phosphonic diester (9 R = R O), generally available through a Michaelis-Arbuzov reaction using the acyl chloride R COCl and the phosphorus(III) ester (R 0)3P, is converted into its / -toluenesulphonylhydrazone (Scheme 2), and the latter is then decomposed by the action of a base, very often simply aqueous KOH or Na2C03. The method was originally applied to esters from acetyl- and benzoyl-phosphonic acids and has since been applied to a wide range of dimethyl (l-oxoalkyl)phosphonates and also to analogous phosphinic esters (10 R = Ph or substituted phenyl)to (l-oxoalk-2-enyl) phosphonic diesters and to (3-oxoalk-l-enyl)phosphonic diesters An exception... [Pg.296]

Occasionally, reactions with 25 show some loss of chemoselectivity and small amounts of phosphorus chloridates are observed thionyl fluoride has been examined with a view to eliminating unwanted reactions. Although trialkyl phosphorus(III) esters give some of the... [Pg.790]

The procedure by which phosphorus chlorides react with acetic acid or anhydride was explored by Van Druten and the existence at room temperature of a number of complex esters established. Presumably these are Cl ... [Pg.257]

Tervalent phosphorus acid esters, and triphenylphosphine, attack 2-bromothiazole (34) at bromine in alcoholic solvents to give thiazole and the oxidised phosphorus compounds. A similar attack of tris(diethylamino)phosphine on the bromine atom of bromopentafluorobenzene was used to prepare a series of main-group-four pentafluorophenyl derivatives, e.g. (35). A full paper has appeared on the fluoridation of trimethylsilyl phosphites, or phosphoramidites, with sulphury chloride fluoride. The mild conditions allowed the preparation of sensitive nucleoside derivatives, e.g. (36) and (37). [Pg.87]

The melting points of these esters are usually much lower than those of the corresponding 3 5 dinitrobenzoates their preparation, therefore, offers no advantages over the latter except for alcohols of high molecular weight and for polyhydroxy compounds. The reagent is, however, cheaper than 3 5 dinitrobenzoyl chloride it hydrolyses in the air so that it should either be stored under light petroleum or be prepared from the acid, when required, by the thionyl chloride or phosphorus pentachloride method. [Pg.263]

Treat the distillate with 2 drops of glacial acetic acid (to destroy the phosphorus esters present) and redistil using the same apparatus as before except that the separatory funnel is replaced by a thermometer. Collect the liquid which passes over at 50-56°. Transfer the acetyl chloride to a weighed glass-stoppered bottle (since cork and rubber stoppers are attacked) and determine the weight. The yield is 22 g. [Pg.368]

Ethyl a-bromopropionate. This preparation illustrates the facile bromination of an acid chloride (propionyl chloride) in the presence of red phosphorus, and the subsequent conversion of the bromoacid chloride into the ethyl ester by direct interaction with ethanol. [Pg.430]

The preparation of 4-methylcoumarin is an example of the Pechmann reaction, which consists in the interaction of a phenol with a 3-ketonic ester In the presence of a condensing agent (sulphuric acid, aluminium chloride, phosphorus oxychloride or pho.sphoric oxide) ... [Pg.853]

Hydroxyalkylthiazoles are also obtained by cyclization or from alkoxyalkyl-thiazoles by hydrolysis (36, 44, 45, 52, 55-57) and by lithium aluminium hydride reduction of the esters of thiazolecarboxylic acids (58-60) or of the thiazoleacetic adds. The Cannizzaro reaction of 4-thiazolealdehyde gives 4-(hydroxymethyl)-thiazole (53). The main reactions of hydroxyalkyl thiazoles are the synthesis of halogenated derivatives by the action of hydrobroraic acid (55, 61-63), thionyl chloride (44, 45, 63-66), phosphoryl chloride (52, 62, 67), phosphorus penta-chloride (58), tribromide (38, 68), esterification (58, 68-71), and elimination that leads to the alkenylthiazoles (49, 72). [Pg.341]

Nitrates Aluminum, BP, cyanides, esters, phosphorus, tin(II) chloride, sodium hypophos-phite, thiocyanates... [Pg.1210]

Pyridazinecarboxamides are prepared from the corresponding esters or acid chlorides with ammonia or amines or by partial hydrolysis of cyanopyridazines. Pyridazinecarboxamides with a variety of substituents are easily dehydrated to nitriles with phosphorus oxychloride and are converted into the corresponding acids by acid or alkaline hydrolysis. They undergo Hofmann degradation to give the corresponding amines, while in the case of two ortho carboxamide groups pyrimidopyridazines are formed. [Pg.33]


See other pages where Phosphorus chlorides esters is mentioned: [Pg.588]    [Pg.991]    [Pg.140]    [Pg.183]    [Pg.208]    [Pg.1435]    [Pg.143]    [Pg.495]    [Pg.495]    [Pg.32]    [Pg.49]    [Pg.83]    [Pg.167]    [Pg.241]    [Pg.413]    [Pg.434]    [Pg.442]    [Pg.22]    [Pg.134]    [Pg.151]    [Pg.431]    [Pg.312]    [Pg.33]    [Pg.127]    [Pg.128]    [Pg.123]   


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