Copper heterobimetallic complexes

A number of stable heterobimetallic copper alkyne complexes have been reported, based on the strategy of using another metal bis(alkynyl) complex as a chelating ligand for copper. The 1,4-diyne [(r -CsFGSiMe Ti-(C=GSiMe3)2]180 (or related complex) was found to stabilize the copper units GuX, with X = alkyl,180,181 vinyl,180... 

Fabbrizzi, L., Montagna, L., Poggi, A., Kaden, T.A. and Siegfried, L.C. 1986. Ditopic receptors for transition metal ions a heterobimetallic nickel(II)-copper(II) bis(macrocyclic) complex and its stepwise oxidation to the tervalent state. Inorg.Chem., 25,2671-2672. 

Other work has demonstrated that it is possible to switch ON and OFF luminescence by reduction/oxidation, and it has been demonstrated that such switching is possible inside an OTTLE cell. Many alkynyl complexes, especially those of rhenium, platinum,copper, silver or gold " are highly luminescent from their excited MLCT or metal perturbed 71 states. This opens up the possibility to significantly influence their emissive properties by redox processes. An interesting example is found in recent work of Wong et Unlike other rhenium(I)-alkynyl complexes, heterobimetallic... 

Free H2 is an extremely weak add with a pK >49 in THF,43 and heterolytic splitting of 2-H2 in relatively electron-rich neutral complexes is usually achieved only by strong bases. For example, copper alkoxides deprotonate W(CO)3(PR3)2(H2) and FeH HjXPRj to give heterobimetallic spedes with bridging hydrides. 

Lang, H., and del Villar, A. (2003). Heterobimetallic Platinum-Copper and Platinum-Silver Transition Metal Complexes Based on cA-[Pt](CsCPh)2 An Overview. J Organomet.Chem., 670,45-55. 

The same group also showed that tris(dithiocarbamate) complexes react with a range of copper(I) salts in acetonitrile giving 1 1, 2 1 and 3 1 heterobimetallic adducts together with polymeric species (Fig. 175), the latter being linked and cross-linked into a novel double-stranded polymer by centrosymmetric displaced step Culfi units (498,1400,1401). In contrast, reaction with [Cu(BF4)2] simply yields [Co2(S2CNR2)s][BF4] and [Cu(S2CNR2)2][BF4] (1118). 

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