Tridentate nitrogen ligands

Scheme 4.15 Preparation of catalyst precursors containing tridentate nitrogen ligands and abilities in catalytic reactions according to Chirik and coworkers.

Guillaumont, D. 2004. Quantum chemistry study of actinide(III) and lanthanide(III) complexes with tridentate nitrogen ligands. Journal of Physical Chemistry 108(33) 6893-6900. 

Figure 4.21 The structure of [Lu(19)2](CH30H)(H20)] + [37]. (Reproduced with permission from C. Piguet, A.R Williams, C. Bemardine and J.C.G. Btinzli, Structural and photophysical properties of lanthanide complexes with planar aromatic tridentate nitrogen ligands as luminescent building blocks for triple-helical structures, Inorganic Chemistry, 32, 4139, 1993. 1993 American Chemical Society.)...

Tridentate nitrogen ligand is one of the useful ligands capping coordination sites of metal ions. Hydrotris(pyrazolyl)borate derivatives have been used for this purpose. The starting material, [LW02(0H)] (L = hydrotris(3,5-dimethylpyrazol-l-yl)borate) was prepared from [LWI(CO)3] via transfer of two oxygen atoms from dimethyl sulfoxide. This reaction required water as the source... 

Tridentate nitrogen ligands form 1 1 uncharged complexes with copper, in contrast to bidentate ligands that form tetrahedral ionic complexes.81 Well-controlled polymers of styrene and MA are obtained with a substituted terpyridine (L-18), whereas the unsubstituted derivative induced a heterogeneous and uncontrolled polymerization.111 A similar controlled polymerization of styrene was reported for a substituted terpyridine-based complex of Cu(II) (Cu-5) coupled with Al(O i-Pr)3.112 A tridentate ligand with two pyridines and one amine (L-19) gave narrow MWDs for styrene, MA, and MMA (MJMn = 1.1 —... 

Tridentate nitrogen ligands have also been used, and an exceptional T -allyl palladium complex containing terpy (2,2 6, 2"-terpyridine) has been obtained as a result of the strong tendency of terpy to maintain tridentate coordination.t " ... 

Scheme 4.95 Ni-catalyzed cross-coupling of alkylzinc halides with alkyl halides in the presence of tridentate nitrogen ligands [292, 293].

Palladium(iv) Complexes with Tridentate Nitrogen Ligands 301... 

Scheme 23.12. Asymmetric epoxidation of vinyl arenes with H2O2 mediated by Ru(II) catalysts bearing Pyboxazine (a) and Pybims (b) as chiral tridentate nitrogen ligands.

In 2011, Xi et al. achieved the complete intermolecular [2 -f 2 -f 2] cycloaddition of terminal alkynes 102 using an in situ-generated low-valent iron complex bearing a tridentate nitrogen ligand (Scheme 6.29) [43]. 

Although [2-f2] cycloaddition reactions such as (7.5.1.2) are rare, an iron complex with a neutral tridentate nitrogen ligand has been shown to catalyze it. Here, as shown by reaction 7.5.1.3, structure 7.67 is involved as an intermediate. 

Kguet C., A. F. Williams, G. Bemardinelli, J.-C. G. Biinzli. Structural and Photophysical Properties of Lanthanide Complexes with Planar Aromatic Tridentate Nitrogen Ligands as Luminescent Building Blocks for Triple-Helical Structures, Inorg. Chem., 32,4139-4149 (1993). 

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