Rapid kinetics, complex and diverse reaction intermediates, and difficult screening make the study of assembly mechanisms of high-nuclearity lanthanide clusters challenging. Here, we synthesize a double-cage dysprosium cluster [Dy60(H2L1)24(OAc)71(O)5(OH)3(H2O)27]·6H2O·6CH3OH·7CH3CN (Dy60) by using a multidentate chelate-coordinated diacylhydrazone ligand. Two Dy30 cages are included in the Dy60 structure, which are connected via an OAc- moiety. The core of Dy60 is composed of 8 triangular Dy3 and 12-fold linear Dy3 units. We further change the alkali added in the reaction system and successfully obtain a single cage-shaped cluster [Dy30(H2L1)12(OAc)36(OH)4(H2O)12]·2OH·10H2O·12CH3OH·13CH3CN (Dy30) with a perfect spherical cavity, which could be considered an intermediate in Dy60 formation. Time-dependent, high-resolution electrospray ionization mass spectrometry (HRESI-MS) is used to track the formation of Dy60. A possible self-assembly mechanism is proposed. We track the formation of Dy30 and the six intermediate fragments are screened.
© 2020. The Author(s).