Conformational structure macrocyclic ring inversion

Inversion at the N center is coupled to conformational changes in a chelate ring. The kinetics of inversion at asymmetric N centers in complexes of tetraaza linear or macrocyclic ligands have received scant attention. There are five configurational isomers of the planar complex Ni([14]aneN4) +, Sec. 3.1.1. The interconversions between such structures are base catalyzed with second-order rate constants covering a small range from 1.2 x 10 to 2.4 x 10 M- s- Refs. 108-110. 

---