Lanthanoid “Bottlebrush” Clusters: Remarkably Elongated Metal–Oxo Core Structures with Controllable Lengths

Large metal–oxo clusters consistently assume spherical or regular polyhedral morphologies rather than high-aspect-ratio structures. Access to elongated core structures has now been achieved by the reaction of lanthanoid salts with a tetrazole-functionalized calix­arene in the presence of a simple carboxylate co-ligand. The resulting Ln19 and Ln12 clusters are constructed from apex-fused Ln5O6 trigonal bipyramids and are formed consistently under a range of reaction conditions and reagent ratios. Altering the carboxylate co-ligand structure reliably controls the cluster length, giving access to a new class of rod-like clusters of variable length.

大型金属氧簇（metal–oxo clusters）通常呈现球形或正则多面体形貌，而非高长径比结构。如今，通过在简单羧酸共配体（carboxylate co-ligand）存在的条件下，使镧系金属盐与四唑功能化杯芳烃（calixarene）发生反应，我们已成功获得伸长型核结构产物。所得到的Ln₁₉与Ln₁₂团簇由顶点融合的Ln₅O₆三角双锥单元构筑而成，且在一系列反应条件与试剂配比下均可稳定生成。通过改变羧酸共配体的结构，可精准调控团簇的长度，从而得到一类长度可调的新型棒状团簇。