Butene complexes with silver

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],... 

The development of methods to effect nucleophilic addition to carbon-carbon double bonds by prior activation with metal cations has been applied, at least in a preliminary way, as a method of pyrrole ring closure. The conversion of butadienes to N-substituted pyrroles can be accomplished in two stages. In acetic add, 1,4-dienes react with PdnCl2 to give tr-allyl complexes with introduction of acetate at C-4. The ir-allyl complexes then react with amines to give a l-amino-4-acetoxy-2-butene (equation 70). When the addition of the amine is carried out in the presence of a silver salt and triphenylphosphine, a pyrrole is isolated, probably by cyclization of the amino-substituted allyl-Pd complex (equation 71) (81CC59). Although this procedure is attractive in terms of the simplicity of the... 

It is interesting to compare the -AH values for the formation of [Ag(l-butene).N03] (-42.4 kJ mol-1) obtained by Francis S2> with that obtained by Quinn et al. for the corresponding bis-complex, [Ag( l-butene)2.BF4] (-50.2 k.T mol-1), i.e. somewhat lower than half. The decomposition pressure of the solid formed from the interaction of butadiene with silver nitrate indicated the presence of two complexes S3> [Ag(C4H6)N03] I and [Ag(C4H6)0 sN03] II. Their enthalpies of formation were found to be -45.2 kJ mol-1 respectively and the proposed structures are as shown below. The more likely structure for II is the polymeric structure (a)... 

Copper, silver, and gold form complexes with olefins of the following composition [CuX(olefin)] (X = C1, Br olefin = ethylene, propylene, butenes, COT, NBD, etc. dienes in these complexes are monodentate ligands), [Cu2X2(COD)2],... 

In copper and silver olefin compounds, alkenes readily undergo exchange. Gold compounds are more stable, and their olefins react with nucleophiles. The compound Au2Cl2(cw-2-butene) reacts with D2O to give 2-butanone. The following d and d electron complexes readily react with nucleophiles Pd(II), Pt(II), Fe(II), etc. 

Methyl vinyl ketone is synthesized industrially by the hydration of vinylacetylene. The reaction is catalyzed by acetates, formates, or sulfates of mercury, silver, cadmium, copper, or zinc in the presence of acids [329,330]. The oxidation of 1-butene to methyl vinyl ketone in 72% yield by the formation of olefin mercuric salt complexes followed by the decomposition of these complexes with acid may become commercially feasible [331]. 

Adsorbed amount of 1 -butene at 80°C is four times larger than n-butane on modified clay by silver impregnation (Figure 3-(c)). Such a high selectivity of 1-butene over n-butane is mainly due to the presence of Ag ions for 7 complexation. Adsorption amounts of other C4 paraffins and olefins are inferred to be almost the same with that of n-butane and 1-butene, respectively. Uptakes of n-butane and 1-butene on modified clay are surely faster than the corresponding components on CMS. But isobutane component can be considerably adsorbed on modified clay. 

Reviews.—Recent reviews involving olefin chemistry include olefin reactions catalysed by transition-metal compounds, transition-metal complexes of olefins and acetylenes, transition-metal-catalysed homogeneous olefin disproportionation, rhodium(i)-catalysed isomerization of linear butenes, catalytic olefin disproportionation, the syn and anti steric course in bi-molecular olefin-forming eliminations, isotope-elfect studies of elimination reactions, chloro-olefinannelation, Friedel-Crafts acylation of alkenes, diene synthesis by boronate fragmentation, reaction of electron-rich olefins with proton-active compounds, stereoselectivity of carbene intermediates in cycloaddition to olefins, hydrocarbon separations using silver(i) systems, oxidation of olefins with mercuric salts, olefin oxidation and related reactions with Group VIII noble-metal compounds, epoxidation of olefins... 

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