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Reactions of bis-1,3-dicarbonyl compounds H 2 L (1) with metal dichlorides of cadmium, manganese and calcium in the presence of aqueous ammonia affords octanuclear supramolecular coordination complexes [M 8 L 8 ]´4 Y (2 ± 5), whereas reaction with magnesium dichloride yields an adamantanoid tetranuclear cluster [(4 NH 4 ) (Mg 4 L a 6 )] (6). Treatment of copper dichloride with diethyl ketipinate 1 a and sodium hydroxide furnishes the double-/triple-decker metallacoronates [{[Na & (Cu 3 L a 3 )BF 4 ]´THFH 2 O} 2 ] (7) and [{Na & (Cu 3 L a 3 )BF 4 } 3´2THF] (8) with an encapsulated sodium ion. Since the 1 H and 13 C NMR spectra of diamagnetic 2 and 5 and paramagnetic 4, 7 and 8 do not unambiguously establish the exact structure of these compounds, exemplary X-ray diffraction analyses of 4, 7 and 8 were carried out.

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For some time we have been working in the field of cage compounds such as [NH,c Fe,Li] (l), originating by the spontaneous self-assembly of preprogrammed bis(bidentate) bridging ligands and suitable metal ions.1'B21 A notable feature of these tetranuclear adamantanoid endoreceptor complexes is their topological equivalence to cryptates (2) .Iz1 [~I We were convinced that the analogy perceived between 1 and 2 is not a special case, but that the use of properly tailored ligands should give access to other metallatopomers. In order to test this hypothesis we treated dialkyl ketipinates 4a,bf5] or tetraketone 4d6' with copper(r1) chloride and aqueous ammonia or potassium hydroxide in methanol, obtaining dark green crystals in each case. The microanalytical data and FAB-MS spectra (FAB = fast atom bombardment) gave initial indications that the products were hexanuclear copper chelate compounds (5) of the general composition [MOH(Cu,L:),].6HOR2, constituting host guest systems topologically equivalent to well-known organocrown ether sandwich complexes 3 [for example, KI(benzo[l5]crown-5),] .I7] In principle, the composition of a coronate is dependent on the cavity diameter of the host. Correspondence between the size of host and guest leads to complexes with 1 : 1 stoichiometry, whereas "oversize" cations result in sandwich complexes with 2: 1 stoichiometry.

Almost the same ligands—completely different metal chelates! Compound 1, R = CO2Me, yields the Mg complex 2 (○ = Mg2+, • = NH 4+) with exohedrally bound ammonium ions by self‐organization; however, 1, R = H, affords the octanuclear Cd complex 3 (○, • = Cd2+). The ammonium ions in 2 can be fully exchanged for primary amines.