Zusammenfassung
Extended investigations of the reaction sequence [Cp' Nb-2(Te-2)H]/CH3Li/[Co-2(CO)(8)] (Cp' = tBUC(5)H(4)) led to the identification of Li-n[3] {3 = [Co9Te6(CO)(8)]; n = 1, 2} salts through their transformation with [PPN]Cl into [PPN](n)[3] (PPN = Ph3PNPPh,). These compounds form in the solid state columnar ([PPN][3]) or undulated 2D ([PPN](2)[3]) supramolecular networks. Electrochemical studies ...
Zusammenfassung
Extended investigations of the reaction sequence [Cp' Nb-2(Te-2)H]/CH3Li/[Co-2(CO)(8)] (Cp' = tBUC(5)H(4)) led to the identification of Li-n[3] {3 = [Co9Te6(CO)(8)]; n = 1, 2} salts through their transformation with [PPN]Cl into [PPN](n)[3] (PPN = Ph3PNPPh,). These compounds form in the solid state columnar ([PPN][3]) or undulated 2D ([PPN](2)[3]) supramolecular networks. Electrochemical studies of [Cp* Nb-2(CO)(2)][3] (Cp* = C5Me5) or [Na(THF)(6)][3] revealed the presence of the redox couples [3](-)/[3](2-)/[3](3-)/[3](4-)/[3](5-) regardless of the nature of the cation, whereas in the anodic part oxidative degradation of the cluster takes place. This behavior is in agreement with the observation that [3](-) containing salts form with PPh3AuCl or dppe decomposition products like [(PPh3)(2)Au][CoCl3PPh3] or [Co(CO)(2)dppe](2)(mu-Te). A neutral cluster comprising the CO@Co-8(mu(4)-Te)(6) core formed in the reaction of [CP* Nb-2(CO)(2)][Co11Te7(CO)(10)] with PPh3AuCl, which gave [Co9Te6(CO)(4)(PPh3)(4)] (4) after oxidative cluster degradation and CO substitution. 4 was characterized by Xray crystallography. DFT calculations carried out on all members of the [3](n) (n = +1 to -5) family and on related species indicate that there is no significant Jahn-Teller distortion (and therefore no connectivity change) for any of the considered electron counts. Magnetic investigations on [PPN][3] show that the ground state of [3](-) is a spin triplet with spins interacting antiferromagnetically in a 1D space. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008).