Phosphonium Phosphides

The crystalline phosphonium phosphide salt [Ph3PMe]+[ C6H2(CF3)3 2P] is reported to have dimensions (6.461a) [3]. The anion can be compared with metal phosphide (6.461b), the phosphonium salt (6.461c) and the phosphonium phosphoride salt in (6.480). While structures (c) and (d) should allow approximate tetrahedral and pyramidal coordination of the F atoms, the fourfold pyramidal arrangement in (f) is quite different. 

The existence of ylidic compounds like (6.462a,b) has been reported [2,33-35], as well as similar type azaphosphorus compounds (7.133). Compounds of type (c) are not yet known although some of type (d) have been reported in recent years. 

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Equivalent P-P and equivalent P-C bond lengths observed in the tetraphosphinine (6.895b) is in accord with either a ylid or phosphonium phosphide formulation [76,77] (Figure 6.24). 

The interesting phosphonium phosphide (7.133) with equivalent P-P bond lengths was reported in 1996. This compound is believed to be formed via an unstable phosphyne [21],... 

What compounds of phosphorus with hydrogen are known Compare the properties of phosphine (hydrogen phosphide) and ammonia. Write the coordination formulas of the phosphonium ion and hypo-phosphorous acid. 

The method of greatest applicability is the reaction of alkali metal phosphides with dihalo-alkanes, -alkenes, etc. (equation 4). Generally this reaction proceeds well and in high yield excess dihaloalkane should be avoided as this leads to the production of phosphonium salts which can contaminate the product. 

With phosphonium halides such as PH4I, the phosphide Si6P2 is obtained ... 

Palladium, hydride, 158 Para anc n, 151 Paraffine, 175 Paratoluidine, 175 Perchloric acid hydrates, 253 Perlite, 310 Phenanthiene, 289 Phenylammonium, phenolate of, 318 Phenylglycolic acid, 294 Phenol, 314, 318, 319 Phosphide of hvdro n, 398 Phosphonium, bromide of, 340 Phosphorus, 184, 284, 334, 396, 410 perchloride, 346 Picric acid. 105, 227 Pinonic acid, 292 Platinum, chlorides, 400 Potash, 393... 

For the above reasons nitrogen forms many compounds of types not formed by other elements of this group, and for this reason we deal separately with the stereochemistry of this element. For example, the only compounds of N and P which are structurally similar are the molecules in which the elements are 3-covalent and the phosphonium and ammonium ions. There are no nitrogen analogues of the phosphorus pentahalides, and there is little resemblance between the oxygen compounds of the two elements. Monatomic ions of nitrogen and phosphorus are known only in the solid state, in the salt-like nitrides and phosphides of the more electropositive elements. The multiple-bonded azide ion, N3, is peculiar to nitrogen. 

The tris(tert-butylsulfanyl)cyclopropenylium ion 11 readily reacted with trialkyl phosphites to give the (cycloprop-2-enyl)phosphonate derivatives 12 but not with triphenyl phosphite, even under more forcing conditions. The reaction with hexamethylphosphorous triamide gave the (cycloprop-2-enyl)phosphonium salt 13. Similarly, the tri-tert-butylcyclopropenylium ion 14 reacted with lithium bis(trimethylsilyl)phosphide affording the 3-phosphanylcyclopropene derivative 15 in high yield. 

CHEMICAL PROPERTIES flammable gas extremely weak base bums with a luminous flame forms the phosphide and liberates hydrogen when passed over heated metal forms phosphonium salts when brought in contact with the halogen acids reacts with air and halogens FP (NA) LFL/UFL (1.6%, 98%) AT (lOO C, 212 = F) HC (NA) HF (5.4 kJ/mol gas at 25°C). 

Triethylphosphine, ( 2115)3 , is prepared in a variety of ways (1) By the action of phosphorus-sodium alloy on ethyl iodide. (2) A double compound of the phosphine with zinc chloride is produced when zinc diethyl reacts with phosphorus trichloride. (3) The phosphine IS formed together with its oxide when zinc diethyl reacts with phosphorus oxychloride. (4) By heating 1 molecular equivalent of phosphonium iodide with 3 molecular equivalents of ethyl alcohol for 6 to 8 hours at 160° to 180° C., tetraethylphosphonium iodide occurring as a by-product. This process yields the hydriodide of the phosphine. (5) By decomposition wdth potassium hydroxide of the base formed when a zinc phosphide, PHZn (prepared by the action of phosphine on zinc diethyl at a temperature not exceeding —4° C.), is heated with ethyl iodide in a sealed tube for 1 hours at 150° (6) By heating... 

The different cations and anions of each molecule are covered in separate chapters. Most of the information on these ionic species results from gas-phase studies or quantum-chemical calculations. Only PHg and PHJ have been obtained to date as ions of salt-like compounds, either in solution or in the solid state PHg, e.g., in the alkali metal phosphides MPHg, where M = Li to Cs and PHJ, e.g., in the phosphonium halides PH4X, where X = Cl, Br, I. 

Sodium phosphate dibasic dihydrate phosphate substitute, detergents Gluconocitrate polyamino EDTA, sodium salt phosphating agent, steel Cobalt phosphate (ous) phosphatizing, metal Sodium acid pyrophosphate phosphatizing, metals Sodium acid pyrophosphate phosphide mfg., metallic Phosphorus, red phosphonium salts... 

Phosphine can be made by the action of water or dilute acids on certain metal phosphides (4.130). Industrially, it is usually made by the action of steam on the element (red) at 280°C (the acid process) (4.131) or by the alternative alkaline process that involves the hydrolysis of white phosphorus (4.131a) but is not favoured since unwanted hydrogen is obtained. Both processes involve competing side reactions and there is some disagreement in the literature. The gas may also be made by the action of caustic potash on phosphonium iodide (4.132), or by heating dry phosphorous acid (4.133) or phosphites (5.214). 

Some phosphines can be obtained from phosphonium halides by the action of metals or metal phosphides (6.401,6.402). 

Alkyl halides react with acyl phosphides to give phosphonium salts (6.371). Some unsaturated salts can be made by thermal dehydrochlorination of suitable phosphonium salts (6.372). 

Phosphinidene Phosphide Phosphinyl Phosphine Phosphinium Phosphonium Phosphonium Phosphoranyl ... 

Extremely toxic at 10 ppm and can be rapidly fatal at 2000 ppm. Some compounds such as phosphonium salts emit phosphine on heating, and some metal phosphides do likewise when in contact with moisture. 

The formation of achiral phosphonium salts (14) or phosphide anions (15) explains the easy racemisation of 13 in the presence of traces of acids or bases. It has been found that 13 can be stabilised by the presence of a mild base, capable of neutralising any trace of protons but unable to form 15. A different way to stabilise secondary phosphines is the quenching of the electron pair by the formation of phosphine boranes (see Section 1.3). 

PH3) A very poisonous colorless gas that is slightly soluble in water. It has a characteristic fishy smell. It can be made by reacting water and calcium phosphide or by the action of yellow phosphorus on a concentrated alkali. Phosphine usually ignites spontaneously in air because of contamination with diphosphane. It decomposes into its elements if heated to 450°C in the absence of oxygen and it burns in oxygen or air to yield phosphorus oxides. It reacts with solutions of metal salts to precipitate phosphides. Like its nitrogen analog ammonia it forms salts, called phosphonium salts. It also forms complex addition compounds with metal ions. 

P-0-, P-Hal-, and P-S-compounds, as well as quaternary phosphonium salts can be reduced with finely divided Na to Na-phosphides, which give phosphines or, with alkyl halides, phosphonium salts.— E ... 

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