Abbau von Koordinationspolymeren bis zum Monomer und Konkurrenz von Polymerisation und Chemischer Schere an Carbazolaten von Yb und Eu mit N-Phenylpiperazin^†

Degradation of Coordination Polymers to the Monomer and Competition of Polymerization and Chemical Scissors on Carbazolates of Yb and Eu with N-Phenylpiperazine

The coordination polymers , Ln = Yb, Eu, Cbz⁻ = carbazolate anion, C₁₂H₈N⁻, can be degraded by the use of strong N-donor ligands like N-phenylpiperazine (Phpip = (C₆H₅)C₄H₈NNH) as chemical scissors. The degradation process for the ytterbium containing polymer ends in the monomeric compound [Yb(Cbz)₃(Phpip)₂]·1/2Phpip and includes an oxidation step Yb^II → Yb^III. Thus the circle of reactions of Yb metal with carbazole (CbzH) starting in liquid NH₃ to the coordination polymer and ending with its degradation by the use of chemical scissors is resolved. Transformation on europium has been started on the base of both metals leading to coordination polymers of the same chemical formula. However already the prelude of reactions differs for Eu as the electride induced reaction of Eu metal with CbzH in liquid ammonia followed by Phpip treatment gives single crystalline [Eu₂(Cbz)₄(NH₃)₂(Phpip)₄]·2Phpip. This dimeric molecule contains Eu^II and ligands of all reaction steps, NH₃, Cbz⁻, Phpip, and is thereby an interesting starting point for the resolution of polymer formation and degradation as well as a competition of these counter reactions.