Potassium phosphides

The phosphides are usually made by direct combination of the elements at elevated temperature. The reactive phosphoms is typically red phosphoms, white phosphoms, or phosphoms vapor. Lithium phosphide [12057-29-3] sodium phosphide [12058-85-4] Na P and potassium phosphide [12260-14-9] iron(III) phosphide [26508-33-8] EeP, and diiron phosphide [1310-43-6] Fe2P, are made in this manner. 

Write the complete Lewis structure for each of the following compounds (a) ammonium chloride (b) potassium phosphide (c) sodium hypochlorite. 

Sodium phosphide (or potassium phosphide) is decomposed by moist air or water, evolving phosphine, which often ignites. 

Phosphine is generated when phosphide salts (i.e., Aluminum phosphide Calcium phosphide Magnesium phosphide Magnesium aluminum phosphide Potassium phosphide Sodium phosphide Stannic phosphide Strontium phosphide Zinc phosphide) come into contact with water. 

Organosilylphosphines are conveniently prepared by cleavage of alkyldiaryl-phosphines with lithium in THF, followed by treatment with chlorotrimethyl-silane,15 and tris(trimethylsilyl)phosphine has been prepared from the reaction of chlorotrimethylsilane with a mixture of sodium and potassium phosphides.16... 

A yellow solid is formed during the decomposition of potassium phosphide by water,2 and this solid is formed in many other reactions which yield the other hydrides, possibly as a secondary product resulting from the decomposition of the hcmiphosphide by water (see p. 80). It is also formed by the exposure of phosphine to light,3 and is one of the products of the action of chlorine upon phosphine. 

Potassium phosphides.-—Phosphine reacts with a solution of potassium in liquefied ammonia to form potassium dihydrophosphide, KH2P, white crystals decomposed by moist air with evolution of phosphine.1 On heating, it is converted into tripotassium phosphide, K3P. A solution of potassium in liquefied ammonia reacts with red phosphorus to form potassium pentaphosphide, KPfi.2 The black product formed from potassium and phosphorus loses its excess of metal in vacuum at 400° to 450° C., yielding dipotassium pentaphosphide, K2P5. It is a lemon-yellow substance with a density of about 2, is unstable in air, and is decomposed by water with formation of solid phosphorus hydride.3... 

One method for the synthesis of cyclic silicon-phosphorus compounds is the reaction of alkaliphosphides with dichlorosilanes [1]. Using sodium/potassium phosphide, -arsenide, -antimonide and -bismutide Na3E/K3E (E = P, As, Sb and Bi) [2] with various di-, tri-, and tetrachloroorganosilanes, cages of the following types (Fig 1.) have been synthesized so far. 

The reactions of chlorooligosilanes with sodium potassium phosphide or arsenide are known to yield cage-like structures composed of SiSi and SiE bonds (E=P, As, Sb, Bi), as shown in Fig. 1 [1]. 

A suspension of sodium potassium phosphide in DME (50% excess) is added to a refluxing solution of 5 in DME. After refluxing for 24 h no reaction occurs and the solid is removed by filtration. The yellow filtrate is again refluxed and a freshly prepared pho hide suspension is added in a molar ratio of 1.5 once more. As can be easily followed by Si NMR spectroscopy the reaction immediately proceeds. From the resulting yellowish grey suspension the salts were removed by filtration. After removal of the solvent in vacuo 3 was crystallized from heptane/DME. 

Fig. 2. Apparatus for preparing sodium-potassium phosphide and reacting it with chlorotrimethylsilane.

The reactions of a series of methylphenylchlorosilanes with a mixed sodium-potassium phosphide reagent have given the related (methylphenylsilyl)phosphines (32). A more detailed study of the products of the reaction of potassium phenylphosphide with dichloromethane has enabled the isolation of the cyclic polyphosphines (33) and (34). The secondary phosphine (35) has... 

Compounds consisting of two elements, or of an element and a radical only, binary compounds, are designated by compound names made up of the name of the more electro-positive, followed by that of the more electro-negative, in which the termination ide has been substituted for tbe terminations ine. on, ogen, ygm, orus, turn, and ur. For example the compound of potassium and chlorine is called potassium chloride, that of potassium and oxygen, potassium oxide, that of potassium and phosphorus, potassium phosphide. 

Ans. ia) K3N, potassium nitride (6) K3P, potassium phosphide (c) KsAs, potassium arsenide. 

The five diastereoisomers are separable by chromatography. Table I. The ether may be rej)laced with the corresponding thio compound, producing five isomers of [18]aneP4S2 in ca. 14% yield. The nitrogen-containing analogue necessitated the use of the potassium phosphide. ... 

This was accomplished by coupling either an amine or a phosphide with a silyl halide, followed by metalation. In the case of the obtained aminosilane, the subsequent metalation proceeded smoothly resulting in a stable aminosilylanion. In the case of phosphorus, we observed the formation of the phosphinosilyl anion by NMR, but the compound was not stable under the reaction conditions and rearranged to give the potassium phosphide. 

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