Metal acetylides silver acetylide

Acetylene can form metal acetylides, e.g. copper or silver acetylide, which on drying become highly explosive service materials require careful selection. 

Propargyl bromide forms explosive metal acetylides when copper or its alloys, silver or mercury are present. 

See related HALOACETYLENE DERIVATIVES, METAL ACETYLIDES See other silver compounds... 

See Silver nitrate Acetylene See other METAL ACETYLIDES... 

There is a danger of explosion in contact with copper, high-copper alloys, mercury or silver (arising from metal acetylide formation). 

Very sensitive to impact or friction, and explodes when moistened with sulfuric acid. See other metal acetylides, silver compounds... 

Acetylenic compounds with replaceable acetylenically bound hydrogen atoms must be kept out of contact with copper, silver, magnesium, mercury or alloys containing them, to avoid formation of explosive metal acetylides. 

Kabanov, A. A. etal., Russ. Chem. Rev., 1975, 44, 538-551 Application of electric fields to various explosive heavy metal derivatives (silver oxalate, barium, copper, lead, silver or thallium azides, or silver acetylide) accelerates the rate of thermal decomposition. Possible mechanisms are discussed. 

Catalytic forms of copper, mercury and silver acetylides, supported on alumina, carbon or silica and used for polymerisation of alkanes, are relatively stable [3], In contact with acetylene, silver and mercury salts will also give explosive acetylides, the mercury derivatives being complex [4], Many of the metal acetylides react violently with oxidants. Impact sensitivities of the dry copper derivatives of acetylene, buten-3-yne and l,3-hexadien-5-yne were determined as 2.4, 2.4 and 4.0 kg m, respectively. The copper derivative of a polyacetylene mixture generated by low-temperature polymerisation of acetylene detonated under 1.2 kg m impact. Sensitivities were much lower for the moist compounds [5], Explosive copper and silver derivatives give non-explosive complexes with trimethyl-, tributyl- or triphenyl-phosphine [6], Formation of silver acetylide on silver-containing solders needs higher acetylene and ammonia concentrations than for formation of copper acetylide. Acetylides are always formed on brass and copper or on silver-containing solders in an atmosphere of acetylene derived from calcium carbide (and which contains traces of phosphine). Silver acetylide is a more efficient explosion initiator than copper acetylide [7],... 

This class of compounds showing explosive instability deals with heavy metals bonded to elements other than nitrogen and contains the separately treated groups GOLD COMPOUNDS LEAD SALTS OF NITRO COMPOUNDS LITHIUM PERALKYLURANATES MERCURY COMPOUNDS METAL ACETYLIDES METAL FULMINATES METAL OXALATES PLATINUM COMPOUNDS PRECIOUS METAL DERIVATIVES SILVER COMPOUNDS... 

Silver is a white, ductile metal occurring naturally in its pure form and in ores (USEPA 1980). Silver has the highest electrical and thermal conductivity of all metals. Some silver compounds are extremely photosensitive and are stable in air and water, except for tarnishing readily when exposed to sulfur compounds (Heyl et al. 1973). Metallic silver is insoluble in water, but many silver salts, such as silver nitrate, are soluble in water to more than 1220 g/L (Table 7.3). In natural environments, silver occurs primarily in the form of the sulfide or is intimately associated with other metal sulfides, especially fhose of lead, copper, iron, and gold, which are all essentially insoluble (USEPA 1980 USPHS 1990). Silver readily forms compounds with antimony, arsenic, selenium, and tellurium (Smith and Carson 1977). Silver has two stable isotopes ( ° Ag and ° Ag) and 20 radioisotopes none of the radioisotopes of silver occurs naturally, and the radioisotope with the longest physical half-life (253 days) is "° Ag. Several compounds of silver are potential explosion hazards silver oxalate decomposes explosively when heated silver acetylide (Ag2C2) is sensitive to detonation on contact and silver azide (AgN3) detonates spontaneously under certain conditions (Smith and Carson 1977). 

The use of silver acetylides to effect useful synthetic transformations has been perhaps more widely reported than the use of any other organosilver compound, as previously reviewed by Pale et al.81 and Sladkov et al.82 Their use, however, in comparison to that of other metal acetylides (Na, Cu, Li), has perhaps been limited by their relatively low reactivity and/or solubility. The silver acetylides are, however, generally comparatively more stable than the more commonly used metal acetylides, as they can be... 

More recently, reactions of alkali metal acetylides, HC2M (M = Li-Cs), with Aul in liquid NH3 and subsequent heating of the solid product in pyridine (Li-K) or in vacuum (Rb, Cs) gave pale yellow M2AuC2.184,185 They contain [Au C C chains, which interact with the alkali metal cations via the C2 units, and are generally similar to the analogous silver compounds.204... 

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