Tetrachloroethylene carbonate

Physical properties of hexachloroethane are Hsted in Table 11. Hexachloroethane is thermally cracked in the gaseous phase at 400—500°C to give tetrachloroethylene, carbon tetrachloride, and chlorine (140). The thermal decomposition may occur by means of radical-chain mechanism involving -C,C1 -C1, or CCl radicals. The decomposition is inhibited by traces of nitric oxide. Powdered 2inc reacts violentiy with hexachloroethane in alcohoHc solutions to give the metal chloride and tetrachloroethylene aluminum gives a less violent reaction (141). Hexachloroethane is unreactive with aqueous alkali and acid at moderate temperatures. However, when heated with soHd caustic above 200°C or with alcohoHc alkaHs at 100°C, decomposition to oxaHc acid takes place. 

Carbona, see Carbon tetrachloride Carbon bichloride, see Tetrachloroethylene Carbon bisulfide, see Carbon disulfide Carbon bisulphide, see Carbon disulfide Carbon chloride, see Carbon tetrachloride Carbon dichloride, see Tetrachloroethylene Carbon disulphide, see Carbon disulfide Carbon hexachloride, see Hexachloroethane Carbon monobrotnide trifluoride, see Bromotrifluoromethane... 

Compound Name Hexachlorocyclopentadiene Tetrachloroethylene Carbon Tetrachloride Perchloromethyl Mercaptan T etrachloroethylene Urea Peroxide Decahydronaphthalene Tetrachloroethylene Hydrogen Peroxide Peracetic Acid... 

Scheme 178 Possible types of nucleophilic attacks to tetrachloroethylene carbonate by Ct.

Also, we discovered that tetrachloroethylene carbonate can be used as a highly effective chlorinating agent for acid chlorides preparation as depicted in scheme 179 (Ref. 231). 

Photochemical perchlorination of ethylene carbonate affords tetrachloroethylene carbonate (V) in high yield (Ref. 229). When (V) is treated with a trace of a nucleophile, it cleaves quantitatively to oxalyl chloride and phosgene [Scheme 177] (Ref. 230). 

Scheme 179 Preparation of acid chlorides using tetrachloroethylene carbonate.

Furthermore, we studied the described dechlorination of tetrachloroethylene carbonate (V) to dichlorovinylene carbonate (VI) with zinc (Ref. 229). (VI) is an interesting intermediate which as a cyclophile permits simultaneous introduction of masked a-hydroxy keto and a-diketo functions respectively into the cycloadducts (Ref. 232). One example is given in scheme 180. 

Trichloroethylene Tetrachloroethylene Carbon tetrachloride 1,1,1-Trlchloroethane 1,2-Dichloroethane Vinyl chloride Methylene chloride... 

Tetrachlorobenzene Sodium hydroxide, Solvent, 2079 Tetrachloroethylene carbonate, Tributylamine, 1042 Tetrachlorosilane, Ethanol, Water, 4173 Titanium, Water, 4919... 

Sulfuric acid and oleum are often used in excess, thereby advantageously functioning as cheap, low-viscosity solvents for the product sulfonic acids which are often quite viscous in pure form. They are always used in liquid form, while sulfur trioxide, on the other hand, is usually employed as a vapor since it is easily vaporized (bp, 44.8°C) and the vapor form is considerably milder than the liquid. Liquid sulfur dioxide is an excellent sulfonation solvent for use with sulfur trioxide and with oleums, and it has been used industrially. Halogenated organic solvents (tetrachloroethylene, carbon tetrachloride, trichlorofluoromethane, etc.) are miscible with sulfur trioxide in all proportions, but not with its hydrates. 

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