Solvent properties phosgene

These substances have excellent solvent properties for nonpolar and slightly polar substances. Chloroform once was used widely as an inhalation anesthetic. However, it has a deleterious effect on the heart and is oxidized slowly by atmospheric oxygen to highly toxic carbonyl dichloride (phosgene, COCl2)-Commercial chloroform contains about 1% ethanol, which destroys any COCl2 formed by oxidation. 

Chemical Properties. Phosgene is readily soluble in organic solvents and fatty oils. In water, phosgene is rapidly hydrolyzed with the formation of hydrochloric acid and carbon dioxide. 

Phosgene dissolves readily in many organic solvents, such as benzene, toluene, xylene, etc., as well as in fats and oils. From these solutions it can be easily removed by a current of dry air. Use is made of this property in marketing phosgene as a 30% solution in toluene. 

It is insoluble in water, though it easily dissolves in many organic solvents (alcohol, benzene, carbon disulphide, acetic acid, acetone, ether, chloroform, carbon tetrachloride, etc.). It is also soluble in several of the other war gases, such as phosgene, chloropicrin, etc. Because of this property, it may be used together with these war gases so as to attain a more complete range of effects. 

Owing to their low flammability and excellent degreasing properties, the chlorinated hydrocarbons are commonly used as solvents in the laboratory, office and industrial workplaces. These materials, however, are particularly susceptible to thermal or photochemical decomposition to phosgene in normal environments. 

Hg(CHjPh)Cl does not appear to react with phosgene at temperatures below which it decomposes to give PhCHjCHjPh [1020]. In contrast, treatment of Hg CH2C(0)H j with phosgene in thf yielded divinyl carbonate, CH j=C(H)0 2C=0 [1461a]. Similarly, treatment of either Hg CH jC(0)R Cl (R = H or Me) or Hg CHjC(0)R j with phosgene in a polar solvent (e.g. nitrobenzene, CHjClj or MeCN) at 20-60 C affords CHj=C(R)0C(0)Cl (i.e. vinyl or isopropenyl chloroformates for a review of their properties, see [61]) in excellent yields [1622]. The work was extended to include R = Ph, CMej or C3H3, and the synthesis of 1-cyclohexenyl chloroformate from mercury biscyclohexanone [1558]. 

CHEMICAL PROPERTIES stable under ordinary conditions of use and storage hazardous polymerization will not occur may form small amounts of phosgene due to unusual exposure to light in the presence of air degrades slowly when exposed to air reacts with chemically active metals, strong caustics, and fuming sulfuric acid attacks most plastics and rubber reaction with water can cause appreciable hydrolysis above 110°C (230°F), hydrolysis and oxidation become rapid not an inert solvent FP (NA) LFL/UFL (NA) AT (NA) HC (NA) HF (-195.0 kJ/mol liquid at 25°C). 

Heavy colorless liquid with a chlorotonn-llke odor that is a poor warning property. Vapor pressure Is 350 mm Hg at 20°C (68 F). Possible thennal-breakdown products include phosgene and hydrogen chloride. Methylene chloride is a solvent with many Industrial and commercial uses (eg, lumiture strippers, carburetor cleaners). 

Solvents vary widely in their toxicological properties. In common they cause dermatitis by removing the natural grease from the skin, and narcosis by acting on the central nervous system additionally some can damage the peripheral nerves, the liver and kidneys and interfere with blood formation and cardiac rhythm. Chlorinated solvents can decompose if exposed to a naked flame to produce acidic fumes (hydrochloric acid and small amounts of phosgene) which are harmful to the lungs. Any harmful effect is related to the amount of solvent absorbed. 

The industrially most relevant polycarbonate (PC) is formed by the reaction of the diol bisphenol A with diphenyl carbonate or phosgene. Formally, polycarbonates can be regarded as polyesters of the acid H2CO3. Polycarbonates are transparent and display good mecdianical and dielectric properties but are unstable against many organic solvents and strong bases. 

The concentrations of chioroform vapour permitted in the iaboratory atmosphere have steadily been reduced in recent years as regulations have been revised. Unfortunately, there appears to be no proven substitute in many of the problems that face lipid analysts. As supplied, chloroform usually contains 0.25 to 2% of added ethanol, which acts as a stabiliser, but also has a considerable effect on the chromatographic properties of the solvent. It can be removed, if there is a need, by a simple washing procedure [163], but photochemical formation of the highly poisonous substance, phosgene, can then occur and the destabilised solvent should not be stored for any length of time. Chloroform-methanol mixtures are powerful irritants when they come in contact with the skin. 

Germann, Cady and Elsey, Jander, Wickert, and Smith have extended the solvent system theory of acids and bases to include non-protonic systems. Germann showed that aluminum chloride in phosgene has typical acid properties. The solution dissolves metals with evolution of carbon monoxide gas and is neutralized... 

The typically acid properties of aluminum chloride in phosgene are due to this increased concentration of solvent cations. Ger-... 

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