Diimine solid state structures

It is noteworthy that this family of complexes had been known for decades, bnt what made the newly introduced derivatives excellent catalysts for polymerizing ethylene was the incorporation of very bulky aryl substituents (e.g. 2, 6-(i-Pr)2C6H3) on the diimine nitrogens. Solid-state structural and computational studies have indicated that the aryl... 

A series of five- and six-coordinate chiral [Mn (salen)] complexes known to be effective AE catalysts has been characterized by X-ray crystallography [56]. Comparison of some of these structures revealed that the ligand geometry around the metal center and the chiral diimine backbone remained remarkably constant, while the salicylidene regions of the complexes adopted a wide range of conformations. The conformational variations observed in the solid state likely reflect accessible solution conformations of the [Mn (salen)] complexes and possibly their oxo counterparts. 

---