Ketiminate, tridentate

Structurally very close to the N,N,O-tridentate ketiminate systems, magnesium complexes bearing bis-amido-oxazolinate complexes 44a-e were used in the PLA preparation from L-lactide in the presence of benzyl alcohol. The low reactivity of 44d, e is due to the presence of a pendant functionality engaging the metal center, and the steric bulk of the phenyl group hindering the coordination of benzyl alcohol or of a monomer to the metal center, contributing to a diminution of the propagation [69]. 

More recently, we have developed aromatic heterocyclic pyrazol-5-one-based tridentate N,N,0-donor ketiminate-supported magnesium and zinc benzyl-alkoxide systems [L2M2(p-OBn)2] where M = Mg 45 or Zn 46, and L = 4-... 

Figure 12 Metal complexes bearing tridentate ketiminate ligands...

In 2007, Lin and coworkers reported the synthesis of dimeric complexes [ [NNO Mg(OBn)]2 bearing tridentate [NNO] amino-ketiminate ligands (66) (Fig. 21) [81]. They acted as potent initiators for the ROP of l-LA, converting 50-200 equiv within 8 min and affording polymers with fully predictable molecular weights... 

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