Bathophenanthroline ligand

In the mechanism of an interfacial catalysis, the structure and reactivity of the interfacial complex is very important, as well as those of the ligand itself. Recently, a powerful technique to measure the dynamic property of the interfacial complex was developed time resolved total reflection fluorometry. This technique was applied for the detection of the interfacial complex of Eu(lII), which was formed at the evanescent region of the interface when bathophenanthroline sulfate (bps) was added to the Eu(lII) with 2-thenoyl-trifuluoroacetone (Htta) extraction system [11]. The experimental observation of the double component luminescence decay profile showed the presence of dinuclear complex at the interface as illustrated in Scheme 5. The lifetime (31 /as) of the dinuclear complex was much shorter than the lifetime (98 /as) for an aqua-Eu(III) ion which has nine co-ordinating water molecules, because of a charge transfer deactivation. 

A broad range of metal centers have been used for the complexation of functional ligands, including beryllium [37], zinc, transition metals such as iridium [38], and the lanthanide metals introduced by Kido [39], especially europium and terbium. Common ligands are phenanthroline (phen), bathophenanthrolin (bath), 2-phenylpyridine (ppy), acetylacetonate (acac), dibenzoylmethanate (dbm), and 11 thenoyltrifluoroacetonate (TTFA). A frequently used complex is the volatile Eu(TTFA)3(phen), 66 [40]. 

Scheme 10.3 CuAAC-accelerating ligands of choice tris(l,2,3-triazolyl)methyl amine (TBTA), water-soluble analogues 11, sulfonated bathophenanthroline 12, tris(benzimidazole)methyl amine (TBiA) 13, and hybrid ligand 14.

Recently, bipyridines and amino alcohols, which were rather unique ligands for conventional nickel-catalyzed cross-coupling reactions, have been shown to be eflective for nickel-catalyzed arylations of secondary alkyl halides. Fu reported that a combination of [Ni(cod)2] and bathophenanthroline 13 catalyzed the cross-... 

Cyanide ions react in an aqueous medium with [Fe(bathophenanthroline)3] to form the mixed-ligand complex [Fe(bathophenanthroline)2(CN)2], which is strongly colored and extractable into chloroform [73]. This reaction can be used for the determination of cyanide with good sensitivity and precision. 

We subsequently found " that the palladium(II) complex of sulfonated bathophenanthroline and related water-soluble diamine ligands are stable, recyclable catalysts for the aerobic oxidation of alcohols in a two-phase aqueous-organic medium whereby the organic phase consists of the alcohol substrate and the carbonyl product (Fig. 7.14). Reactions were generally complete in 5 h at 100°C/30 bar air with as little as 0.25 mol% catalyst. No organic solvent is required (unless the substrate is a solid) and the product is easily recovered by phase separation. The catalyst is stable and remains in the aqueous phase, facilitating recychng to the next batch. 

Suzuki Cross-coupling Reactions. The formation of sp -sp carbon-carbon bonds is possible through the coupling of primary and secondary alkyl iodides and bromides with unsaturated boronic acids, under nickel catalysis using bathophenanthroline as ligand. As a result, an important variety of compounds bearing different functionalities can be coupled under mild conditions with good yields (eq 6). ... 

Applications. Bathophenanthroline and transition metal complexes with bathophenanthroline as ligand are compounds that exhibit interesting photophysical and photochemical properties for the application in dye-sensitized solar cells or OLEDs. Further, metal-bathophenanthroline complexes can be used for the quantitative determination of nucleic acids. 

Some of the most representative ligands are the commercially available sul-fonated bathophenanthroline BPDS, the tris(benzimidazole) (BimC Ajg, and the tris-(triazole) TBTA ligands. 

Recently, nickel-catalyzed cross-couplings of organosUicon reagents with unactivated secondary alkyl bromides have been disclosed. Functional groups such as fluoride, chloride, ether, lactones, ketones, acetals, and cyanides are stable under the reaction conditions. Bathophenanthroline appears to be the best ligand for these transformations [96]. 

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