Ligand preorganization

Aliphatic amines, which are hard bases, are unfavorable for coordination to soft Ni°. If the principles of ligand preorganization and donor prepositioning are applied, however, (diamine)Ni° complexes are accessible, which has been demonstrated for complex (1020) with a rigid N,N -dimethyl-3,7-diazabicyclo[3.3.1 ]nonane ligand.2468... 

Using the preorganized bis(amidinate) ligands featuring 9,9-dimethyl-xanthene backbones, several new dizirconium complexes have been prepared. For example, hexa(amido) complexes were obtained by reaction of the ligands with 2 equivalents of Zr(NMe2)4 (Scheme 212). ... 

Layer-by-layer Ru3 cluster-based multilayers were fabricated onto preorganized self-assembled monolayer gold electrode surfaces by Abe et al. [15], in which [Ru3(q3-0)( i-0Ac)6(4,4/-bpy)2(C0)] was utilized as the synthetic precursor. The stepwise connection of oxo-centered triruthenium cluster units onto the gold electrode surface is a feasible approach for construction of Ru3 cluster-based oligomers on a solid surface, in which the bridging ligand 4,4 -bipyridine appears to mediate weak cluster-cluster electronic interaction between the Ru3 cluster centers. 

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