Metal bi-phenolates

Practically all the above considered reactions for the synthesis of bisfethernaphthalic anhydrides) were employed for preparing bis- thio-ethernaphthalic anhydrides) [92, 93, 107-110] bis-thiophenolates were used instead of alkali metals bis-phenolates ... 

Capacchione, C. Proto, A. Ebeling, H. Miilhaupt, R. MdUer, K. Spaniol, T. R Okuda, J. AnciUary ligand effect on single-site styrene polymerization Isospecificity of group 4 metal bis(phenolate) catalysts. J. Am. Chem. Soc. 2003,125, 4964-4965. 

In other methods of metallizing dyes in the receiver, metal chelates are used in a polymeric matrix. Examples of ligands for the metal ion include diazabicyclo[2.2.2]octane,128 the 2,2 -bis-phenol (60)129 and the iminodiacetic acid (61).,3°... 

Metal-based reagents are often used to promote one- and two-electron oxidations of arenols. Radical-mediated C-0 coupling reactions of aryloxy radicals can, of course, lead to ortho-quinol derivatives, but the preparative value of such an approach is poor and essentially limited to intramolecular cases. For example, certain bis-phenols such as 36a-c have been spiroannulated in good yields by diradical C-0 coupling under favorable one-electron oxidation regimes (Figure 12) [65-67]. 

It is only fair when reviewing syntheses to mention unsuccessful reactions so as to outline any shortcomings of a particular reagent, and this has been done throughout this review. Sah et al. have recently reported that reaction of the metallated lithium phenolate (31) with either nitrobenzene or bis(trimethyl-silyl) peroxide gave only starting material, while reaction with trimethyl borate followed by oxidation furnished a complex mixture. 

Bis 8-quinolmato metal complexes are representative examples of distorted octahedral structures of the type (87). It was noted that these systems bear a topological resemblance to the chiral, octahedral, active metal sites that have been proposed for supported Ziegler-Natta catalysts, and are interesting for modeling catalytic properties. Similar comportment has been observed with diamine bis (phenolate) ligands. ... 

Mononuclear [W(0)Cl(0Ar)(Tp )] and dinuclear [ W(0)C-(Tp ) 2 (pt-bis(phenolate))] complexes have been synthesized characterized by electrochemistry, EPR, magnetic susceptibility, UV/Vis/NIR spectroelectrochemistry, and X-ray with the aim to evaluate the electronic and magnetic interaction between the redox-active, paramagnetic metal centers.187... 

A classical oxidation reaction that involves radicals is the phenolic oxidative coupling, which is introduced in Section 10.5.A.i. In this reaction, electron transfer from a metal salt to a bis(phenol) leads to intramolecular coupling and a quinone product. The early yields were poor. For example, Barton reacted 219 with potassium ferricyanide [K3(Fe(CN)6l and the product was aryl radical 220. This radical reacted with the second phenolic ring in an intramolecular process that gave 221. Loss of a hydrogen led to the quinone narwedine (222) in a synthesis of galanthamine. 53 jjje yield of 222, however, was only 1.4% under optimal... 

Oiring with nucleophiles does not require any specific cure site. As it was shown in the case of bis-phenols, curing requires the additional presence of an accelerator and a metal oxide base. The results described in this paper support the following mechanisms ... 

St 1 - Reaction between bis-phenol, phosphoniim accelerator and metal oxide to give Ri,P QArCXI. 

Several years ago, Kol and coworkers began investigating the group 4 metal chemistry of amine bis(phenolate) ligands These ligands feature several useful properties, in particular (1) a broad... 

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