Polychelate effects

It should be noted that the entropy component of the polychelate effect is largely controlled by the same contributions as for LMWM, i.e., translation, rotation, symmetry, isomerism, oscillation, internal rotation and solvation contributions [41]. Besides both the chelate and polychelate effects depend greatly on the size of the chelate cycle. In this case the PCMU obey the known Chugaev rule by... 

Thus, at the local level the polychelate effect is close to the chelate one provided the model reaction components are selected correctly. However, in doing so one has to account for the polymeric nature of chelating ligand and the associated contributions to the chelation entropy. In the reaction... 

By analogy with the chelate effect [38] its polychelate variety can be defined [39] as a gain of free energy (5AGpcbel) in the addition of a CML to the metal ion... 

Thus, as compared with the chelate effect, its polychelate form will include two additional terms for the molecular and supramolecular levels of the spatial PCMU arrangement. 

---