Crystal structures of three anionic lanthanide–aluminium [3.3.1] metallacryptate complexes

The three isomorphous [3.3.1] metallacryptate complexes bis­(pyridinium) di­aqua­dipyridine­hexa­kis­[μ3-salicyl­hydroximato(3−)]bis­[μ2-salicyl­hydroxim­ato(1−)]hexa­aluminiumgadolinium–pyridine–water (1/7.396/1), (C5H6N)2[GdAl6(C7H6NO3)2(C7H4NO3)7(C5H5N)1.855(H2O)2]·7.396C5H5N·H2O or [Hpy]2[GdAl6(H2shi)2(shi)7(py)1.855(H2O)2]·7.396py·H2O, 1, bis­(pyridinium) di­aqua­dipyridine­hexa­kis­[μ3-salicyl­hydroximato(3−)]bis­[μ2-salicyl­hydroxim­ato(1−)]hexa­aluminiumdysprosium–pyridine–water (1/7.429/1), (C5H6N)2[DyAl6(C7H6NO3)2(C7H4NO3)7(C5H5N)1.855(H2O)2]·7.429C5H5N·H2O or [Hpy]2[DyAl6(H2shi)2(shi)7(py)1.891(H2O)2]·7.429py·H2O, 2, and bis­(pyrid­in­ium) di­aqua­dipyridine­hexa­kis­[μ3-salicyl­hydroximato(3−)]bis­[μ2-salicyl­hydrox­imato(1−)]hexa­aluminiumytterbium–pyridine–water (1/7.386/1), (C5H6N)2[YbAl6(C7H6NO3)2(C7H4NO3)7(C5H5N)1.855(H2O)2]·7.429C5H5N·H2O or [Hpy]2[YbAl6(H2shi)2(shi)7(py)1.818(H2O)2]·7.386py·H2O, 3, where Hpy+ is pyridinium, shi3− is salicyl­hydroximate, and py is pyridine, consist of an aluminium-based metallacryptand that captures an LnIII ion in the central cavity. The metallacryptand portions are comprised of an Al—N—O repeat unit; thus, they can be considered three-dimensional metallacrowns. The encapsulated LnIII ions are nine-coordinate with a spherical capped-square-anti­prism geometry, while the six AlIII ions are all octa­hedral. Four of the AlIII ions are chiral centers with 2 Δ and 2 Λ stereoconfigurations. The remaining two AlIII ions have trans chelate rings from two different shi3− ligands. For 1–3, a section of the main mol­ecule is disordered induced by the presence or absence of a pyridine ligand coordinated to one of the AlIII ions. In the absence of the pyridine moiety, an H2shi− ligand moves into the space otherwise occupied by the pyridine and the phenol oxygen atom coordinates to the AlIII ion. The movement of the H2shi− ligand induces movement for the LnIII ion, for another AlIII ion that also binds the same H2shi− ligand, and for one of the shi3− ligands coordinated to the latter AlIII ion. For 1–3 the occupancy ratio of the metallacryptand portions refined to 0.8550 (13):0.1450 (13), to 0.8909 (13):0.1091 (13), and to 0.8181 (14):0.1819 (14), respectively.