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Phosphinates, hydrolysis

Many of these reactions are reversible, and for the stronger nucleophiles they usually proceed the fastest. Typical examples are the addition of ammonia, amines, phosphines, and bisulfite. Alkaline conditions permit the addition of mercaptans, sulfides, ketones, nitroalkanes, and alcohols to acrylamide. Good examples of alcohol reactions are those involving polymeric alcohols such as poly(vinyl alcohol), cellulose, and starch. The alkaline conditions employed with these reactions result in partial hydrolysis of the amide, yielding mixed carbamojdethyl and carboxyethyl products. [Pg.133]

The reaction with sodium sulfite or bisulfite (5,11) to yield sodium-P-sulfopropionamide [19298-89-6] (C3H7N04S-Na) is very useful since it can be used as a scavenger for acrylamide monomer. The reaction proceeds very rapidly even at room temperature, and the product has low toxicity. Reactions with phosphines and phosphine oxides have been studied (12), and the products are potentially useful because of thek fire retardant properties. Reactions with sulfide and dithiocarbamates proceed readily but have no appHcations (5). However, the reaction with mercaptide ions has been used for analytical purposes (13)). Water reacts with the amide group (5) to form hydrolysis products, and other hydroxy compounds, such as alcohols and phenols, react readily to form ether compounds. Primary aUphatic alcohols are the most reactive and the reactions are compHcated by partial hydrolysis of the amide groups by any water present. [Pg.133]

Thiols and phosphines add to maleic anhydride to give a-thiosuccinic anhydrides (82) and phosphoranylidene—maleic anhydride adducts (83). Triethyl phosphite [122-52-1] reacts with maleic anhydride to give the yhde stmcture (23) (84). Hydrolysis of this adduct (23) leads to succinic acid... [Pg.452]

Hydroxyall l Hydroperoxyall l Peroxides. There is evidence that hydroxyalkyl hydroperoxyalkyl peroxides (2, X = OH, Y = OOH) exist in equihbrium with their corresponding carbonyl compounds and other a-oxygen-substituted peroxides. For example, reaction with acyl haUdes yields diperoxyesters. Dilute acid hydrolysis yields the corresponding ketone (44). Reduction with phosphines yields di(hydroxyalkyl) peroxides and dehydration results in formation of cycHc diperoxides (4). [Pg.116]

Ai lepiesents an aiyl group. Diaiyl products are obtained after long reaction times. Other Friedel-Crafts catalysts, eg, ZnCl2, FeCl2, FIF, and BF, can also be used. In most cases, stoichiometric amounts of the catalyst ate requited. Flowever, strong complexation of the phosphine by the catalyst necessitates separation by vacuum distillation, hydrolysis, or addition of reagents such as POCl to form more stable aluminum chloride complexes. Whereas yields up to 70—80% are possible for some aryl derivatives, yields of aliphatic derivatives are generally much less (19). [Pg.361]

All phosphoms oxides are obtained by direct oxidation of phosphoms, but only phosphoms(V) oxide is produced commercially. This is in part because of the stabiUty of phosphoms pentoxide and the tendency for the intermediate oxidation states to undergo disproportionation to mixtures. Besides the oxides mentioned above, other lower oxides of phosphoms can be formed but which are poorly understood. These are commonly termed lower oxides of phosphoms (LOOPs) and are mixtures of usually water-insoluble, yeUow-to-orange, and poorly characteri2ed polymers (58). LOOPs are often formed as a disproportionation by-product in a number of reactions, eg, in combustion of phosphoms with an inadequate air supply, in hydrolysis of a phosphoms trihahde with less than a stoichiometric amount of water, and in various reactions of phosphoms haUdes or phosphonic acid. LOOPs appear to have a backbone of phosphoms atoms having —OH, =0, and —H pendent groups and is often represented by an approximate formula, (P OH). LOOPs may either hydroly2e slowly, be pyrophoric, or pyroly2e rapidly and yield diphosphine-contaminated phosphine. LOOP can also decompose explosively in the presence of moisture and air near 150° C. [Pg.371]

Phosphine generated by the above procedures is usually contaminated to varying degrees with diphosphine, which renders it spontaneously flammable. Pure phosphine can be produced by hydrolysis of phosphonium iodide [12125-09-6] PH I, which can be made by the action of water on a mixture of phosphoms and diphosphoms tetraiodide [13455-00-0] (71). [Pg.377]

Pentavalent phosphorus derivatives can be converted to phosphonyl halides or phosphine oxides by partial hydrolysis or by other oxygen donors. [Pg.381]

Phosphonic (phosphorous) acid, produced by hydrolysis of PCl, is for the most part consumed captively. It has also been offered as a flaked product and a 70 wt % solution by Rhc ne-Poulenc. Phosphonic acid is a by-product from manufacturing carboxyHc acid chlorides and alkaH peroxides. Additional by-product phosphonic acid is recovered in the manufacture of phosphinic acid. [Pg.383]

Conversion o( organic azides with phosphines or phosphites to Immophosphoranes (phosphazo compounds) and their hydrolysis to amines. [Pg.359]

Phosphinamides are stable to catalytic hydrogenation, used to cleave benzyl-derived protective groups, and to hydrazine. The rate of hydrolysis of phosphin-... [Pg.375]

Phosphides are binary compounds containing anionic phosphorus (P ). Heavy metal, alkali, and alkaline earth metal phosphides exist but few of them are commercially important. Phosphides hydrolyze to the flammable and toxic gas phosphine (PH3). The hydrolysis reaction of aluminum phosphide is given below ... [Pg.175]

Alkaline hydrolysis of PH4I (for very pure phosphine) ... [Pg.493]

A remarkable transformation of [(> -Ph2BpZ2)Mo(CO)2(i -pentadienyl)] (90OM1862) is the transformation with phosphines or phosphites of this 16-valence-electron species into 18-electron complexes hydrolysis leads to profound changes in the coordination sphere yielding 60. [Pg.194]

The Mitsunobu reaction was applied to the synthesis of pyrrolo[l,2-d [, 2,4]triazines from pyrrole derivative 71. Thus reduction of 71 gave alcohol 72, which on treatment with diethylazodicarboxylate and triphenyl phosphine gave 74 via the open chain intermediate 73. Hydrolysis of 74 gave 75 (84AG517) (Scheme 18). [Pg.49]

Starting from (OC)5MnSiR2H (R = Me, Ph, Cl), the p-silylene complex 70 is accessible via the oxidative addition of the Si —H bond to Pt(C2H4.)(PPh3)2 and Pt(PPh3)4, respectively. Structure 70 can be functionalized by displacement of the phosphine ligands alcoholysis and hydrolysis of the compound 70 leads to silicon-free complexes [175]. [Pg.34]

P-coupling occurs in the formation of azophosphonic esters [ArN2PO(OCH3)2] from diazonium salts and dimethyl phosphite [HPO(OCH3)2] (Suckfull and Hau-brich, 1958). P-coupled intermediates are formed in the reaction between diazonium salts and tertiary phosphines, studied by Horner and Stohr (1953), and by Horner and Hoffmann (1956). The P-azo compound is hydrolyzed to triphenylphosphine oxide, but if a second equivalent of the tertiary phosphine is available, phenyl-hydrazine is finally obtained along with the phosphine oxide (Scheme 6-26 Horner and Hoffmann, 1958). It is likely that an aryldiazene (ArN = NH) is an intermediate in the hydrolysis step of the P-azo compounds. [Pg.126]

Rhodium, iodotetrakis(difluoro(diethylamino)-phosphine)-, 4, 924 Rhodium, pentaamminethiocyanato-base hydrolysis, 1, 504 Rhodium, pentaammincurea-linkage isomerism, 4, 961 Rhodium, pentaammine(urea)-decomposition, 1,186... [Pg.211]

The product is relatively sensitive to basic conditions, showing both polymerization and addition of water. Therefore alkaline conditions must be avoided. Neutralization serves to convert monophenylphosphinic acid (formed by hydrolysis of unreacted, unextracted dichlorophenylphosphine) to the monosodium salt, thereby preventing its subsequent extraction from water along with the phosphine oxide. [Pg.75]

There are many parallels between phosphates and sulfates of aliphatic alcohols. Both types of surfactants contain ester bonds undergoing hydrolysis in acid solutions. In that case the starting materials are received once more. By dry heating of the salts above a temperature of 140°C destruction will occur forming the corresponding alkenes and an inorganic acid salt. In the same way as sulfonic and sulfinic acids are formed by C-S bonds, C-P bonds lead to phosphonic and phosphinic acids. [Pg.552]

Aliphatic hydrocarbons such as hexane also have been reported to react with PCI3 and AICI3. Surface-active esters of phosphinic acids are obtained in good yields by treatment of the intermediate addition compound with an alcohol or phenol followed by hydrolysis [172] see Eqs. (103) to (105) ... [Pg.587]

The stability of phosphinous amides depends, to a large extent, on the substituents at phosphorus and nitrogen. Normally, tetrasubstituted and N,P,P-trisubstituted phosphinous amides are stable and well-known compounds. The parent compound H2PNH2 is a volatile compound that is formed on hydrolysis of a solid state solution mixture of magnesium phosphide and magnesium... [Pg.79]

The hydrolysis of phosphinous amides leading to their constituents, amine and phosphinous acid, is an easy process that is usually followed by the selfcondensation of the acid to yield the diphosphane monoxides 21 [117, 118] (Scheme 21). [Pg.89]

We have investigated the reaction of NH phosphinous amides with diphenyl-cyclopropanone. The products were unequivocally identified as the corresponding p-phosphinyl carboxamides 27 resulting from the hydrolysis of a presumed heterocyclic intermediate (Scheme 28) These results await publication. [Pg.92]


See other pages where Phosphinates, hydrolysis is mentioned: [Pg.456]    [Pg.377]    [Pg.377]    [Pg.377]    [Pg.179]    [Pg.49]    [Pg.378]    [Pg.498]    [Pg.75]    [Pg.267]    [Pg.562]    [Pg.345]    [Pg.110]    [Pg.146]    [Pg.193]    [Pg.213]    [Pg.74]    [Pg.9]    [Pg.81]   
See also in sourсe #XX -- [ Pg.598 , Pg.606 , Pg.607 ]




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Ethylene phosphinate, hydrolysis

Phosphine oxides hydrolysis

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