The tetradentate imino-carboxylate ligand [L]
2- chelates the equatorial sites of Ni
II to give thecomplex [Ni(L)(MeOH)
2] in which a Ni
II center is bound in an octahedral coordination environment withMeOH ligands occupying the axial sites. Lanthanide (Ln) and Group II metal ions (M) template theaggregation of six [Ni(L)] fragments into the octahedral cage aggregates {M[Ni(L)]
6}
x+ (
1: M = Sr
II;
x = 2,
2: M = Ba
II;
x = 2,
3: M = La
III;
x = 3,
4: M = Ce
III;
x = 3,
5: M = Pr
III;
x = 3, and
6: M = Nd
III;
x = 3).In the presence of Group I cations, however, aggregates composed of the alkali metal-oxide cations templatevarious cage compounds. Thus, Na
+ forms the trigonal bipyramidal [Na
5O]
3+ core within a tricapped trigonalprismatic [Ni(L)]
9 aggregate to give {(Na
5O)
[Ni(L)]
9(MeOH)
3}(BF
4)
2·OH·CH
3OH,
7. Li
+ and Na
+ togetherform a mixed Li
+/Na
+ core comprising distorted trigonal bipyramidal [Na
3Li
2O]
3+ within an approximatelyanti-square prismatic [Ni(L)]
8 cage in {(Na
3Li
2O)
[Ni(L)]
8(CH
3OH)
1.3(BF
4)
0.7}(BF
4)
2.3·(CH
3OH)
2.75·(C
4H
10O)
0.5,
8, while in the presence of Li
+, a tetrahedral [Li
4O]
2+ core within a hexanuclear open cage [Ni(L)]
6 in{(Li
4O)
[Ni(L)]
6(CH
3OH)
3}2ClO
4·1.85CH
3OH,
9, is produced. In the presence of H
2O, the Cs
+ cation inducesthe aggregation of the [Ni(L)(H
2O)
2] monomer to give the cluster Cs
2[Ni(L)(H
2O)
2]
6·2I·4CH
3OH·5.25H
2O,
10. Analysis by electronic spectroscopy and mass spectrometry indicates that in solution the trend in stabilityfollows the order
1-
6 >
7 >
8 ~
9. Magnetic susceptibility data indicate that there is net antiferromagneticexchange between magnetic centers within the cages.