Macrobicycles axial

Although two cations are often observed to complex in a dinuclear fashion in the axial macrobicycles, as noted in the previous paragraphs, lateral macrobicycles (Figure 1) are clearly designed for incorporation of two metal ions.9,171,172 These two metal ions are by construction necessarily in chemically different environments, which can greatly affect both chemical and physical properties. For example, in the bis-copper(II) complex of (49b) the two copper ions exhibit greatly different redox potentials (+ 550 and + 70 mV vs. NHE in propylene carbonate).9... 

Figure 8. Templating anions used in the synthesis of macrobicyclic receptor 83. Receptor yields are quoted, as are shifts of the NMR peaks for the included anion. Receptor yield quoted under conditions of more concentrated guest. ea = axial proton, e = equatorial proton. AS could not be analyzed due to signal overlap. Not complexed (no upheld shift of guest protons). [Reprinted with permission from M. Fujita, S. Nagas, and K. Ogura, J. Am. Chem. Soc., 117, 1649 (1995). Copyright 1995 American Chemical Society.]...

Figure L Dijferent types of binucleating macrocycles a) large rings, b) bis-macrocycles, c) axial macrobicycles, d) lateral macrobicycles, and e) cylindrical macrobicycles.

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