| Abstract
| - New hexafluoroacetylacetonato and trifluoroacetato olefin complexes of copper(I) have been prepared, and the solid-state structures of some of them have been determined. The equilibrium constants for the carbonylation reactions of Cu(CF3COO)(olefin) (olefin = tbve, van) (2Cu(CF3COO)(olefin) + 2CO ⇄ [Cu(CF3COO)(CO)]2 + 2(olefin)) and of Cu(hfacac)(olefin) (Cu(hfacac)(olefin) + CO ⇆ Cu(hfacac)(CO) + olefin) have been measured at different temperatures.
- New hexafluoroacetylacetonate (hfacac) and trifluoroacetato olefin complexes of copper(I)of the general formulas Cu(hfacac)(olefin) and Cu(CF3COO)(olefin) have been prepared fromCu2O/hfacacH/olefin or Cu(CF3COO)(toluene)0.5/olefin systems. The structures of [Cu(hfacac)(coe)], [Cu(hfacac)(van)], [Cu(μ-CF3COO)(tbve)]n, and [Cu(μ-CF3COO)(van)]2·C7H8 have beendetermined by X-ray diffraction methods, where coe = cyclooctene, van = 4-vinylanisole,and tbve = tert-butyl vinyl ether. In the solid state, the 4-vinylanisole/trifluoroacetate complex[Cu(CF3COO)(van)]2 is dimeric with two carboxylato groups symmetrically bridging twocopper atoms, while the tert-butyl vinyl ether derivative [Cu(μ-CF3COO)(tbve)]n is polymericwith single [CF3COO]- bridges between adjacent copper atoms. Olefin hfacac complexes aremonomeric, and considering the two oxygen atoms and the midpoint of the double bond ofthe coordinated olefin, the copper atom lies in a nearly trigonal-planar environment. Thecarbonylation reactions of Cu(CF3COO)(olefin), (olefin = tbve, van; 2Cu(CF3COO)(olefin) +2CO ⇆ [Cu(CF3COO)(CO)]2 + 2(olefin)) and of Cu(hfacac)(olefin) (olefin = coe, 1,5-cyclooctadiene (cod), norbornene (nbe), van; Cu(hfacac)(olefin) + CO ⇆ Cu(hfacac)(CO) +olefin) have been studied gas volumetrically, and the equilibrium constants for thedisplacement of the coordinated olefin by carbon monoxide have been determined at differenttemperatures. Some hypotheses on the copper−olefin bond have been formulated on thebasis of structural, thermodynamic and spectroscopic (13C NMR) data.
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