Surface Modification of High-Nuclearity Lanthanide Clusters: Two Tetramers Constructed by Cage-Shaped {Dy₂₆} Clusters and Isonicotinate Linkers

By incorporation of NO3- ligands with trigonal planar geometry as surface modifiers into the lanthanide cluster core backbone to remarkably improve the dimension of cluster cores, two novel lanthanide cluster compounds, Dy30I(μ3-OH)24(μ3-O)6(NO3)9(IN)41(OH)3(H2O)38 (1) and Dy104I4(μ3-OH)80(μ3-O)24(NO3)36(IN)125(OH)19(H2O)167 (2) (HIN = isonicotinic acid), have been obtained under hydrothermal conditions. Single-crystal X-ray diffraction shows that in both cluster compounds, the block blocks of [Dy26(μ3-OH)20(μ3-O)6(NO3)9I]36+, {Dy26}, are the largest cage-shaped lanthanide cluster cores known. Compound 1 is the first tetramer based on the linkage of two different types of high-nuclearity lanthanide clusters and IN ligands, while compound 2 represents the first tetramer constructed by {Dy26} clusters and IN linkers.