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As a consequence of our recent success in isolating and characterizing the first crystalline cryptatium species, the redox properties of a series of cryptates have been analyzed in DMF using cyclic voltammetry. A total of eight cryptates, derived from six cryptands, were studied (see structures in the text). These were the Na+, Ca2+, and La3+ cryptates of tris(bipyridyl) (1-Na+, 1-Ca2+, 1-La3+) and the Na+ complexes of the other five ligands, 2-6. Except for 6-Na+, which exhibited irreversible behavior, and for 2-Na+, which, as expected, had only one redox couple, all of the cryptates showed at least three quasi-reversible redox couples. For 1-La3+ a total of six cathodic waves were observed. A pronounced effect was observed for the reduction potentials when the central metal cation of the cryptate was changed. Thus for 1-Na+ the first reduction potential occurs at -2.40 V (vs ferrocene/ferrocenium, Fc/Fc+), while the corresponding value for I-La3+ is -1.76 V. On the other hand, for all of the Na+ cryptates, the redox potential of each of the individual substituent groups (bipyridyl, bithiazole, dimethylbipyrimidine) was approximately independent of the other substituents present in the molecule, although the reduction state of the complex affected these potentials. For example, the reduction potential for the bithiazole group was the same for the sodium complexes of 2 and 3 and almost the same for the first reduction of 4-Na+. Similarly, the reduction of the two bipyridyls of 3 and 5 occurred at the same potentials as those observed for the second and third reductions of I-Na+. All of the reported redox processes correspond to ligand-centered orbitals, not to those of the metals, a result consistent with the spatially-isolated orbital theory which is accepted for bipyridyl complexes of Ru2+.