Mercury oxychloride

A. J. Balard found mercury immediately decomposes hypochlorous acid without the disengagement of any gas, but mercury oxychloride is formed. P. Grouvelle reported previously that when chlorine acts on mercuric oxide suspended in water, mercury oxychloride, very slightly soluble in cold water, is formed. L. J. Thenard found that the liquid contained both chloride and chlorate of mercury, also in soln. A. J. Balard, however, believed that these bodies are formed consecutively, and that their existence was preceded by that of a mercuric hypochlorite, as takes place with the salts of silver, and, as previously indicated, he prepared hypochlorous acid by the action of chlorine on mercuric oxide suspended in water. No mercury hypobromite has yet been isolated. There is a possible formation of mercury hypoiodite, or more probably of hypoiodous acid, when iodine is shaken up with... 

Mercuric Orthoarsenate, Hg8(As04)2, is obtained by precipitating a solution of mercuric nitrate with a solution of sodium mono- or dihydrogen arsenate, or by dropping aqueous arsenic acid into excess of mercuric nitrate solution.4 It is a heavy citron-yellow powder. Hot water dissolves it slightly without decomposition, and shining crystals may separate from the cooled solution. Hydrochloric acid dissolves it freely, nitric acid less readily, and arsenic acid not at all. Brine solution converts it into red-brown mercury oxychloride. Potassium bromide solution colours it brown, and a yellow residue is ultimately left. Potassium iodide forms mercuric iodide. 

When acetylene is absorbed, again under pressure and in the presence of aluminum chloride or mercury oxychloride as catalyst, the... 

In a 2-1. three-necked flask fitted with a mercury-sealed stirrer (Note 1), a reflux condenser connected to a calcium chloride tube, and a thermometer is placed 360 g. (406 ml., 5 moles) of dry tetrahydrofuran (Note 2). The flask is surrounded by an ice bath, stirring is started, and 256 g. (153 ml., 1.67 moles) of phosphorus oxychloride is added rapidly. The mixture is cooled to 10" 15°, and 50 ml. of concentrated sulfuric acid (sp. gr. 1.84) is added during the comse of 3-10 minutes at a rate that does not cause the temperature to rise above 40°. The ice bath is then removed and the mixture is heated cautiously over a low luminous flame until an exothermic reaction becomes evident at about 88-90° (Note 3). By moderate cooling or warming as may be required the temperature is maintained at 90-100° until the exo-thermic reaction ceases, as indicated by the increased rate of licating required to maintain the reaction temperature, and thereafter for an additional 10 minutes (Note 4). Six hundred milliliters of water is added, the mixture is heated under reflux for 30 minutes and then distilled through a downward condenser until the vapor temperature reaches 99 100° (Note 5). 

In a 5-L, three-necked, round-bottomed flask equipped with a rubber- or mercury-sealed mechanical stirrer and a reflux condenser carrying a drying tube are placed 340 g. (4 moles) of cyanoacetic acid (Note 1) and 2 1. of anhydrous ether. To the stirred solution, 834 g. (4 moles) of phosphorus pentachloride is added in portions through the third neck of the flask, which is sealed between additions. The mixture is cooled occasionally with an ice bath to prevent excessive refluxing, and, after the addition is complete, stirring is continued for 0.5 hour or until the phosphorus pentachloride dissolves completely. The reflux condenser is removed and replaced with apparatus for downward distillation (Note 2), and the ether is distilled from a water bath at 50-60° (Note 3), after which most of the phosphorus oxychloride is removed at reduced pressure (20-25 mm. with a bath temperature of 55-65°) (Note 4), the receiver being cooled in an ice-salt bath. The red, oily residue is dissolved in 200 ml. of benzene and the benzene and residual phosphorus oxychloride distilled under reduced pressure. This operation is repeated with 200 ml. of fresh benzene to ensure complete removal of phosphorus oxychloride (Note 5). The residue is then cooled to room temperature (Note 6) and is transferred to a 500-ml. pressure-... 

Phosphorus oxychloride [ 10025-87-3] M 153.3, b 105.5°, n 1.461, d 1.675. Distilled under reduced pressure to separate from the bulk of the HCl and the phosphoric acid, the middle fraction being distilled into ampoules containing a little purified mercury. These ampoules are sealed and stored in the dark for a 4-6 weeks with occasional shaking to facilitate reaction of any free chloride with the mercury. The POCI3 is then again fractionally distilled and stored in sealed ampoules in the dark until used [Herber JACS 82 792 7960]. Lewis and Sowerby [JCS 336 1957 refluxed their distilled POCI3 with Na wire for 4h, then removed the Na and again distilled. 

Like sulphuryl chloride, pyrosulphuryl chloride can convert many elements, e.g. sulphur, phosphorus, antimony and mercury, into the corresponding chlorides, with simultaneous formation of sulphur dioxide and trioxide.2 In the reaction between pyrosulphuryl chloride and phosphorus pentachloride or trichloride, there are obtained phosphorus oxychloride, sulphur dioxide and chlorine. 

Thenaldehyde (thiophene-2-carbaldehyde) is readily available via the Vilsmeier-Haack reaction of DMF with thiophene catalyzed by phosphorus oxychloride. The Sommelet reaction with 2-chloromethylthiophene also gives reasonable yields (63AHC(l)l). Likewise, thiophene is readily acylated with acyl anhydrides or acid chlorides (equation 14), using mild Friedel-Crafts catalysts, such as tin(IV) chloride, zinc chloride, boron trifluoride, titanium tetrachloride, mercury(II) chloride, iodine and even silica-alumina gels or low-calcium-content montmorillonite clays (52HC(3)l). 

It is best prepared by the action of silver, zinc or lead fluoride on P0C13.2 3 The oxychloride is allowed to drop gradually on to anhydrous zinc fluoride in a brass tube at 40° to 50° C. The gas passes out through a lead tube, then through a condenser at - 20° C. to retain POClg, through a tube of zinc chloride to absorb the last traces of oxychloride, and finally is collected over mercury. 

IV.14 CHLORIDES, Cl- Solubility Most chlorides are soluble in water. Mercury(I) chloride, Hg2Cl2, silver chloride, AgCl, lead chloride, PbCl2 (this is sparingly soluble in cold but readily soluble in boiling water), copper(I) chloride, CuCl, bismuth oxychloride, BiOCl, antimony oxychloride, SbOCl, and mercury(II) oxychloride, Hg2OCl2, are insoluble in water. 

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