Silicon oxide phosgene

Liquid perchloryl fluoride is a typical nonpolar solvent. Most inorganic and organic salts are insoluble in it. Conversely, most covalent, essentially nonpolar substances, boiling within about 50°G of perchloryl fluoride, are completely miscible, e.g., chlorine, boron trifluoride, sulfur hexafluoride, silicon tetrafluoride, phosgene, nitrous oxide, chlorine trifluoride, chlorofluorocarbons, silicon tetrachloride, sulfuryl chloride, dinitrogen tetroxide, and thionyl chloride 106). 

As silicon(IV) oxide is the only common oxide which is not chlorinated by phosgene (see Section 9.4.4) [360], the reaction between phosgene and silicon(IV) chloride was examined both experimentally and theoretically [654] ... 

Silicon(IV) oxide is, uniquely amongst the common oxides, not chlorinated by phosgene below 650 C [360]. Indeed, metal silicates at temperatures up to 1500 C appear to react according to the following simplified equation [120] ... 

Although bulk silicon(IV) oxide is not chlorinated by phosgene, it does slowly chlorinate the surface [866]. This phenomenon has been used to chlorinate the surfaces of chrysotile asbestos and nonexpanded vermiculite for grafting to polystyrene for use as a filler for polymers and elastomers [1383,1384]. Moreover, in the presence of aluminium(III) chloride, phosgene will convert silica gel into silicon(IV) chloride at between 400 and 700 C [208a,208b]. 

The reaction of phosgene with spent platinum-containing or palladium-containing catalysts on aluminium(IIl) oxide, silicon(IV) oxide, or carbon supports at 140-450 C has been used as part of a recovery process [20,231,1864a,1864c], and car exhaust oxidation catalysts can be reactivated by heating in phosgene at 260 "C [1251],... 

PHOSGEN (German) (75-44-5) Poisonous gas. Decomposes slowly with water, producing hydrochloric acid and carbon monoxide. Reacts violently with strong oxidizers, anhydrous ammonia, isopropanol, chemically active metals, silicon tetrahydride, sodium. Forms shock-sensitive material with potassium. Incompatible with /ert-butylazidoformate, sodium azide. Attacks most metals in moist conditions however, it may not affect monel, tantalum, or glass-lined equipment. Note Sodium hydroxide or anhydrous ammonia has been used to neutralize this gas. 

One of the serious drawbacks of the Wittig reaction is the unavoidable production of triphenylphosphane oxide in stoichiometric quantities. Whilst its direct reduction with boron, aluminium or silicon hydrides would be possible, these reagents are too expensive for a viable process. In fact, distilled triphenylphosphane oxide is reacted with phosgene, generated in situ, to give the corresponding dichloride, which is then reduced with metals, like aluminium. [55]... 

Carbonothioic acid, 0-(6-chloro-3-phenyl-4-pyridazinyl) S-octyl ester. See Pyridate, Carbonothioic dichloride. See Thiophosgene Carbon oxide. See Carbon monoxide Carbon oxide sulfide. See Carbonyl sulfide Carbon oxychloride. See Phosgene Carbon oxysulfide. See Carbonyl sulfide Carbon silicide. See Silicon carbide Carbon sulfide. See Carbon disulfide Carbon tet. See Carbon tetrachloride Carbon tetraboride. See Boron carbide Carbon tetrabromide CAS 558-13-4 EINECS/ELINCS 209-189-6 UN 2516... 

---