Phosphorus III Chloride

The synthesis of phosphorus (III) chloride sometimes offers experimental difficulty. The following synthesis proceeds smoothly, gives good yields, and is entirely satisfactory for the preparation of this compound. The apparatus is simple and easy to assemble. 

The chlorine tank is placed on a platform scales and connected to the apparatus. The tank is balanced by the 

Two hundred grams of dry red phosphorus is placed in the flask, t Excess phosphorus must be present to inhibit 

A 1-lb. weight is now placed on the platform of the scales. The chlorine is added as rapidly as possible until the lever arm returns to its zero point at this point 453 g. (1 lb.) of chlorine wiU have been added. After the addition of the chlorine, the flask is disconnected and the necks are closed with rubber stoppers. The phosphorus (III) chloride is then distilled by using a water bath and an ordinary condenser. It fumes in moist air and should be stored in a glass-stoppered or sealed bottle. The excess phosphorus may be recovered for future use. The yield, based on the amount of chlorine added, is about 94 per cent of the theoretical. 

Phosphoi us(III) chloride is a clear colorless liquid having a boiling point of 75.9° and a specific gravity of 1.574 (21°). 

Cleavage of Ethers. PBrs has been used to cleave diisopropyl ether to isopropyl bromide.  

Reaction with Ketones. A regioselective dibromination of a diketone has been reported (eq 4).  

Related Reagents. Many related reagents are available for the conversion of alcohols to bromides (see Phosphorus(ni) Bromide and related reagents cited therein). 

Solubility sol benzene, CHCI3, CH2CI2 ether, CS2 dec in water or alcohols. 

Form Supplied in water-white liquid widely available. 

---

Here again the simple formulation [Sb ] is used to represent all the cationic species present.) The hydrolysis is reversible and the precipitate dissolves in hydrochloric acid and the trichloride is reformed. This reaction is in sharp contrast to the reactions of phosphorus(III) chloride. 

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. 

Martynov, I.V., A.N. Ivanov, T.A. Epishina, and V.B. Sokolov. "Reaction of 1,1-Dichloro-l-nitrosoalkanes with Phosphorus (III) Chlorides." Seriya Khimicheskaya 9 (1988) 2128-2132 (In Russian). 

The basic method used to prepare 1, 2, and 3 was the known reaction (6,7) of phosphorus (III) chlorides with acetals. This was first applied to the preparation of the a-methoxyallylphos-phine oxide 1, as shown in equation (a), and subsequently extended (8) to a wide range of aryl and alkyl derivatives of 1. ... 

Hz). Several pieces of spectroscopic evidence lead to the conclusion the Me5C5 ring of V is not bonded in the monohapto manner. First, the 1h and 13c spectra of V indicate that the ring and Me carbons of the Me5C5 moiety are equivalent moreover, the equivalence of the methyl groups persists to -100°C and -80°C in lH and 13c NMR experiments, respectively. Second, the 31p chemical shift of V (111.0 ppm) is 33.8 ppm upfield (i.e. shielded) compared to that of the phosphorus(III) chloride precursor, 2Z 1° aH cases reported to date, phosphenium ion for-... 

III) cyanide in 1863.2 A second article3 by these authors discussed in some detail the chemical reactions of this substance. No further comment has appeared in the literature on the preparation or the properties of this compound until recently.4 Synthesis was accomplished by mixing phosphorus (III) chloride and silver cyanide (in chloroform) and heating in a sealed tube for several hours at 120 to 140°. After cooling, the tube was opened and the chloroform and unreacted phosphorus (III) chloride removed by evaporation. The phosphorus (III) cyanide was then obtained from the residue by sublimation. The yield was reported to be about 85% by this method. 

The resulting solution of n-butylmagnesium bromide is cooled to 0° with an ice-salt bath, and a solution of 8.7 ml. (13.7 g. 0.10 mol) of redistilled phosphorus (III) chloride (density, 1.57) in 50 ml. of anhydrous ethyl ether is added dropwise with stirring over a period of about an hour. The mixture is then refluxed by warming for % hour, cooled below 0° in an ice-salt bath (ca. hour minimum) and treated with 250 ml. of an ice-cold aqueous solution containing 50 g. of ammonium chloride. ... 

Tetrakis[phosphorus(III) chloride] nickel has been prepared by the reaction of nickel carbonyl with phosphorus-(III) chloride at room temperature.1 The synthesis of this compound as described below is based on this method. 

Tetrakis[phosphorus(III) chloride] nickel is a pale yellow crystalline solid at room temperature and becomes colorless on cooling to about — 30°. This compound is stable in air when dry and unreactive with water at room temperature for a period of several days. It reacts slowly in the cold with dilute acids and with concentrated sulfuric or hydrochloric acid, but reacts rapidly in hot acid solutions. The compound reacts rapidly with ammonium hydroxide but more slowly with sodium hydroxide.1 It is reported that no decomposition occurs below 120° when the solid is heated, but that at higher temperatures the solid is decomposed and phosphorus (III) chloride is liberated 1 however, decomposition at 80° has been observed. Tetrakis[phos-phorus(III) chloride] nickel appears to be nonvolatile. 

Nickel (0) complex compounds, non-electrolytes, with phosphorus-(III) chloride, Ni(PCI3)4, 6 201 Nickel(I) complex compounds,... 

Phosphorus, mixture of, with diphosphorus tetraiodide, 2 143 Phosphorus (III) bromide, 2 147 Phosphorus(III) chloride, 2 145 Phosphorus (V) chloride, 1 99 Phosphorus (III) S-chloroethoxydi-chloride, 4 66... 

Phosphorus(V) oxybromide, 2 151 Phosphorus(V) sulfobromide, 2 153 Phdsphorus(V) sulfobromodifluo-ride, formation of, from phosphorus (V) sulfobromide, 2 154 Phosphorus (V) sulfochloride, 4 71 from phosphorus (III) chloride, aluminum chloride, and sulfur, 4 71... 

The usual method of preparing phosphorous acid from phosphorus (III) chloride and water is complicated by the necessity of avoiding any rise in temperature which might lead to the formation of phosphoric acid by disproportionation. This tendency to disproportionate makes direct reaction between equivalent weights of pure phosphorus-(III) chloride and water, or concentration of dilute solutions of phosphorous acid by evaporation on a steam bath, impossible. 

Six hundred milliliters of carbon tetrachloride and 200 g. of freshly distilled phosphorus (III) chloride (1.46 mols) are placed in a 1.5-1., three-necked flask which is equipped with a 125-ml. dropping funnel, a mechanical stirrer, and a con-... 

Diethyl phosphite was probably first prepared in 1854 by the reaction between alcohol and phosphorus(III) chloride.1 It can also be prepared from phosphorus(III) oxide and alcohol,2 from phosphorous acid and diazoethane,3 or from lead phosphite and ethyl iodide.4... 

Diethyl phosphite is generally produced by the reaction of phosphorus (III) chloride with absolute alcohol. Good yields are difficult to obtain unless special precautions are taken. The by-product hydrogen chloride tends to react with the diethyl phosphite to form additional ethyl chloride and phosphorous acid ... 

Dioctyl phosphite can be produced by the usual method of preparing phosphite esters, i.e., by allowing octanol to react with phosphorus (III) chloride ... 

Ethyl dichlorophosphite and methyl dichlorophosphite have been prepared by the reaction of 1 mol of the appropriate alcohol with 1 mol of phosphorus(III) chloride.1 The ethyl compound has also been prepared from triethyl phosphite and phosphorus(III) chloride.2 The method outlined below is essentially the former however, several improvements have been incorporated. Among the difficulties encountered in the preparation of these compounds are the following Side reactions occur between the generated hydrogen chloride and the ester, giving an alkyl chloride and phosphorous acid disproportionation may occur in the case of the ethyl ester, the necessary vacuum distillation causes losses of the relatively low boiling product. 

Two hundred seventy-five grams of phosphorus(III) chloride (2 mols) is weighed into a 500-ml., round-bottomed, three-necked flask equipped with standard-taper ground-glass joints and cooled by means of an ice-salt or Dry Ice bath. The necks of the flask are fitted, respectively, with a dropping funnel, a mercury-sealed, motor-driven stirrer, ... 

Care must be exercised in disposing of the waste phos-phorus(III) chloride and the distillation residue. The waste phosphorus(III) chloride may be added in small increments to a large volume of cold water. Each portion is permitted to react and dissolve before the next portion is added. If phosphorus (III) chloride is added to warm water, the reaction is violent and flashes of flame may appear on the surface of the water. 

In this synthesis, the reaction is confined primarily to the first step by adding 1 mol of ethylene chlorohydrin to 1 mol of precooled phosphorus(III) chloride. 

Chloroethyl dichlorophosphite may also be prepared by allowing ethylene oxide to condense with phosphorus(III) chloride.1... 

The apparatus and procedure for the preparation of 2-chloroethyl dichlorophosphite are essentially the same as described for the analogous silicon and sulfuryl compounds (synthesis 30). One hundred thirty-seven and one-half grams of reagent-grade phosphorus (III) chloride (1.0 mol) is allowed to react with 80.5 g. of freshly distilled, anhydrous ethylene chlorohydrin (1.0 mol) in a 500-ml. flask under the conditions set forth in the cited synthesis. Approximately 1 hour is required for the introduction of the ethylene chlorohydrin. 

Several procedures have been reported for the synthesis of phosphorus (V) sulfochloride. These include the reaction of phosphorus(V) chloride with hydrogen sulfide,1,2 of phosphorus (III) chloride with sulfur,3 4 of carbon tetrachloride with phosphorus(V) sulfide,5 and of phosphorus(V) chloride with phosphorus(V) sulfide.5 The second and fourth methods form the bases for the two syntheses presented here. 

Preparation from Phosphorus (III) Chloride, Aluminum Trichloride, and Elemental Sulfur... 

This method of synthesis is essentially that of Knotz.4 Phosphorus(III) chloride and sulfur are caused to react in... 

The ratio IPCI3 1S 0.02A1C13 is critical. The quantities of reagents employed are optional provided that the ratio is maintained. Excess phosphorus (III) chloride renders separation of the final product difficult, whereas excess aluminum chloride causes the reaction to go too rapidly for adequate control. The aluminum chloride used should be white. The yellow form promotes a more rapid reaction however, the resulting yields are lower. 

Phosphorus(III) fluoride can be prepared by the reaction of antimony (III) fluoride with phosphorus (III) chloride, using antimony (V) chloride as a catalyst,1 or by heating copper phosphide with lead fluoride.2 The procedure described here involves the reaction of arsenic(III) fluoride with phosphorus (III) chloride, using antimony(Y) chloride as a catalyst.3,4... 

After the apparatus is assembled and thoroughly dried, 13.7 g. of freshly distilled phosphorus(III) chloride (0.10 mol) is introduced into the reaction flask, and 13.2 g. of arsenic (III) fluoride (0.10 mol) (synthesis 50) containing a few drops of antimony (V) chloride J is placed in the dropping funnel. The phosphorus (III) fluoride is readily generated by allowing the arsenic (III) fluoride to drop slowly into the phosphorus(III) chloride the reaction proceeds smoothly at room temperature and becomes more rapid with time. The gases formed by the reaction are led from the reaction flask through a trap cooled by an acetone-Dry Ice bath, to... 

---