The first neutral homoleptic lanthanoid pyrazolates, including the mixed oxidation state species [Yb2(But2pz)5] (But2pz = 3,5-di-tert-butylpyrazolate), from a simple new synthesis of pyrazolate complexes

Abstract

Reaction of 3,5-di-tert-butylpyrazole (Bu^t₂pzH) with lanthanoid metals and mercury at 220 °C in the absence of an added solvent yields [Ln(Bu^t₂pz)₃] (Ln = Nd, Sm), [Eu(Bu^t₂pz)₂] and [Yb₂(Bu^t₂pz)₅], which is a mixed oxidation state complex with the structural arrangement [(η²-Bu^t₂- pz)Yb^II(µ-η²∶η²-Bu^t₂pz)₂Yb^III(η²-Bu^t₂pz)₂].