Bidentate Schiff base ligand

The electrochemistry of Tc complexes containing either two variously substituted bidentate 8-ox type ligands [TcOCl(Lb)2], one 8-ox ligand, and one bidentate Schiff-base ligand [TcOCl(Lb)(La)], or one 8-ox ligand and one tridentate dianionic Schiff-base ligand such as... 

Macrocyclic ligands of biological importance as thiophenolate-containing Schiff-base macrocycles and their amine analogs (see review [138]) and new helical complexes with bis(bidentate) SchifF-base ligand [139] were also described. 

Ruthenium complexes bearing bidentate Schiff base ligands as efficient catalysts for organic and polymer syntheses 05CCR(249)3055. 

First-Generation Ruthenium Indenylidene Catalysts Bearing a Bidentate Schiff Base Ligand... 

Scheme 14.14 Preparation of ruthenium indenylidene catalysts bearing a bidentate Schiff base ligand.

Figure 12.4 Ruthenium catalysts coordinated with N,0-bidentate Schiff-base ligands.

Incorporation of a bidentate Schiff base ligand into Ru-benzylidene complexes has been initially performed by Grubbs et al. flic resulting complexes showed high thermal stability and high tolerance towards polar solvents, yet seemed to be poor initiators in metathesis reactions, although some activity in metathesis at higher temperatures was observed. 

Structures of these complexes have been unambiguously determined by means of infrared (IR), Raman, H NMR, and C NMR spectroscopy, and corroborated with data from elemental analyses. An important feature of these complexes is that the labile 77-cymene group is present along with the better ligated bidentate Schiff base ligand. Having optimized the reaction conditions for this procedure, two new arene-Ru complexes, 68 and 69 (Rj = t-Bu, R2 = /-Pr), could be prepared in the same way (Scheme 38). ... 

Scheme 5. Synthesis of a homobimetallic ruthenium-(cyclodiene) complex bearing bidentate Schiff base ligands.

In this contribution, we wish to highlight our introduction of bidentate Schiff base ligands with formation of 4, which is an extremely stable catalyst type. We will show that this extreme stability is concomitant with lower activity. On the other hand, it will also be demonstrated that bypassing this lack of reactivity by simple heating and the introduction of acid additives is simple and provides a catalyst system with extra features such as storage of the catalyst in the monomer without undesired reaction. 

Nickel. The self-assembly of NP complexes of new bis-bidentate Schiff base ligands has been investigated.NMR spectroscopy has been used to study adduct formation of bis(A/ -diisopropoxythiophosphorylthioben-zamido)Ni(II) with pyridine. ... 

Latency effects due to the N,0-bidentate Schiff base ligands in benzylidene complexes 36 were also reported by Verpoort and co-workers. For these systems, addition of a controlled amount of hydrochloric acid or trichlorosilane... 

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