Macrocycles hole size

Factors influencing the macrocyclic hole size. The hole size of a macrocyclic ligand is a fundamental structural parameter which will usually influence, to a large degree, the properties of resultant metal complexes relative to those of the corresponding non-cyclic ligands. The large number of X-ray diffraction studies now complete for macrocyclic systems makes it possible to define many of the parameters which affect hole size... 

Figure 9.4 Geometrical determination of the macrocycle hole size[263].

A major focus in the study of mixed metal ion systems has been to examine metal ion discrimination. In particular, two specific mechanisms can be attributed to metal ion discrimination macrocyclic hole size and what Lindoy has termed as a dislocation mechaiusm. The key to this... 

In fact, even in his earliest works Pedersen found that primary ammonium compounds do form complexes with crowns whereas secondary, tertiary, and quaternary ammonium ions do not [45,46]. For the first time, it was ascribed to the mismatch of macrocyclic hole size and groups other than NH.f. 

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