Metal halides: metathesis

See Sodium azide See METAL NON-METALLIDES METAL HALIDES METATHESIS REACTIONS... 

Basic Alcoholysis of Metal Halides Metathesis Reaction... 

Other RhX(CO)(PPh3)2 compounds can be made as shown in Figure 2.23 metathesis with an alkali metal halide or pseudohalide is often convenient, but the most versatile route, as with the iridium analogues, is a two-stage process in which the fluoro complex is first prepared, the fluorine then being readily displaced. 

Group 14 metal halides also undergo metathesis reactions. For instance, organotin compounds are prepared on an industrial scale using organoaluminum reagents. These reactions take place because tin is a softer Lewis acid than aluminum, and carbon (in an alkyl group, represented by R) is a softer Lewis base than chlorine ... 

Phosphides and amides are closely related, as a synthetic route is based on metathesis of metal amides, especially the respective trimethylsilyl amides, with the appropriate free acidic phosphine or an anion derived therefrom. Reaction of metal halides and trisilylphosphines is an alternative for preparing metal phosphides. 

Titanium and vanadium nitrides may be prepared by a metathesis reaction of their tetrachlorides with the nitride, initiated by heat or friction. The reaction is potentially explosive. Other transition metal halides may cause ampules to explode after thermal initiation when anhydrous and were invariably found to do so when the hydrates were used. 

The ionic P-P bond polarization renders P-phosphino-NHPs highly active reactants for various metathesis and addition reactions at exceedingly mild conditions. Metathesis is observed in reactions with alcohols, chloroalkanes, and complex transition metal halides (Schemes 11 and 12) [39, 73], Of particular interest are the reactions with chlorotrimethylstannane which yield equilibria that are driven by a subtle balance of P-X bond strengths to yield either diphosphines or P-chloro-NHPs as preferred product (Scheme 11). Chlorotrimethylsilane does not react with... 

Dithiophosphato metal complexes are usually prepared by metathesis of metal halides with alkali metal or ammonium salts. A convenient method uses the redox reaction of his th iophosphory 1 )d is ulfanes (RO)2(S)PSSP(S)(OR)2, with metal species in low oxidation states resulting in the insertion of the metal into the sulfur-sulfur bond.24 Recently it was used for the synthesis of long alkyl chain, liquid platinum(II) dithiophosphates25 and for the synthesis of Ru (CO)2[S2P(OPr%]2 from Ru3(CO)i2 with (Pr 0)2(S)PSSP(S)(0Pr,)2.26... 

Metal dithiophosphinato complexes are usually prepared by metathesis of metal halides with alkali metal or ammonium dithiophoshinates, but can also be conveniently prepared by reactions of /i .v(thiophosphinyl)disul fanes, R2(S)PSSP(S)R2, with metal species.87 The electrochemical oxidation of metals in acetonitrile solution, in the presence of diphenylphosphine and sulfur affords M(S2PPh2)2 (M = Co, Zn, Cd),88 but this is not a preparative method. 

Solid-state metathesis reactions. For a number of compounds, solid-state metathesis (exchange) reactions have the advantages of a rapid high-yield method that starts from room-temperature solids and needs little equipment. The principle behind these reactions is to use the exothermicity of formation of a salt to rapidly produce a compound. We may say that for instance a metal halide is combined with an alkali (or alkaline earth) compound of a /7-block element to produce the wanted product together with a salt which is then washed away with water or alcohol. Metathesis reactions have been used successfully in the preparation of several crystalline refractory materials such as borides, chalcogenides, nitrides. 

These are usually reactions of anhydrous transition and B metal halides with dry alkali metal salts such as the sulphides, nitrides, phosphides, arsenides etc. to give exchange of anions. They tend to be very exothermic with higher valence halides and are frequently initiated by mild warming or grinding. Metathesis is... 

Living polymerization by metal halide-based metathesis catalysts... 

Metal cyanides(and cyano complexes), 216 Metal derivatives of organofluorine compounds, 217 IV-Metal derivatives, 218 Metal dusts, 220 Metal fires, 222 Metal fulminates, 222 Metal halides, 222 Metal—halocarbon incidents, 225 Metal halogenates, 226 Metal hydrazides, 226 Metal hydrides, 226 Metal hypochlorites, 228 Metallurgical sample preparation, 228 Metal nitrates, 229 Metal nitrites, 231 Metal nitrophenoxides, 232 Metal non-metallides, 232 Metal oxalates, 233 Metal oxides, 234 Metal oxohalogenates, 236 Metal oxometallates, 236 Metal oxonon-metallates, 237 Metal perchlorates, 238 Metal peroxides, 239 Metal peroxomolybdates, 240 Metal phosphinates, 240 Metal phosphorus trisulfides, 240 Metal picramates, 241 Metal pnictides, 241 Metal polyhalohalogenates, 241 Metal pyruvate nitrophenylhydrazones, 241 Metals, 242 Metal salicylates, 243 Metal salts, 243 Metal sulfates, 244 Metal sulfides, 244 Metal thiocyanates, 246 Metathesis reactions, 246 Microwave oven heating, 246 Mild steel, 247 Milk powder, 248... 

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