Deprotonation reactions of the aminocarbyne complex trans-[ReCl(CNH2)(dppe)2][BF4](dppe = Ph2PCH2CH2PPh2). Synthesis and properties of the cyano-complexes trans-[Re(CN)L(dppe)2](L = NCR, N2, CO or CCHPh) and crystal structure of trans-[Re(CN)(NCMe)(dppe)2]PriOH

The reaction of the aminocarbyne complex trans-[ReCl(CNH2)(dppe)2][BF4] with NBu4OH, under N2 or CO, afforded the cyano-dinitrogen or -carbonyl compound trans-[Re(CN)L(dppe)2](L = N2 or CO), respectively, whereas in the presence of an organonitrile or of phenylacetylene (under argon) the nitrile or the vinylidene complexes trans-[Re(CN)L(dppe)2](L = NCMe, NCPh, NCC6H4Me-4 or CCHPh, respectively) were obtained. Spectroscopic, FAB mass spectrometric and electrochemical data are reported and discussed in terms of the structural and electronic properties of these complexes. Electrochemical parameters which measure the electron richness and the polarizability of the trans-{Re(CN)(dppe)2} centre have been estimated and the cyanide ligand shown to present a very low capacity to buffer changes in the electron density at the metal upon changing the trans ligand. The crystal structure of trans-[Re(CN)(NCMe)(dppe)2]·PriOH has been determined.

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