Nickel Complexes with N-Hetaryl 1,2-Diimine Ligands

3 Nickel Complexes with N-Hetaryl 1,2-Diimine Ligands 

Reaction of hgands 20-28 with one equivalent of (chmethoxyethane)NiBr2 under inert conditions affords the corresponding (diimine)NiBr2 complexes 29-37 in good yield (Chart 3.3). 

They are air-stable as sohds, but shghdy air-sensitive in solution and thermally very stable (without a detectable melting point up to 200 C). The highly colored (dark brown) and paramagnetic compounds are fairly polar and therefore only slightly soluble in common organic apolar solvents. Therefore, spectroscopic char- 

4 Diimine Nickel and Palladium Complexes with 2,6-Dibromo-4-methylphenyl Croups 

Another appealing steric congruence exists between 2,6-diisopropylphenyl and 2,6-dibromophenyl groups (Fig. 3.4). Note though fhat the isopropyl group has quite different dynamics. 

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