TAP ligands

The trends in the properties described for this series of HAT complexes, are similar for the corresponding series based on the TAP ligand [92], although HAT complexes are more oxidising than TAP complexes. As will be illustrated further, the modulation of the oxidation power will be reflected in the photoreactivity of the Ru(II) complexes versus the various DNA bases. 

In order to confirm the nickel oxidation state in the active entity and to study the influence of the composition of its coordination sphere [coordination number, nature of the trialkylphosphine (TAP) ligands] on the catalytic performances, we have used a set of silica-supported unsaturated Ni complexes [58] with a given number of TAP ligands of different electronic and steric properties [59,60],... 

In 2003, Verkade disclosed details of the arylation of nitriles using his TAP ligands and NaHMDS as base in toluene, and also observed diarylations when using acetonitrile [235]. 

It is also noteworthy that complexes containing ligands such as TAP, HAT, bpz (2,2 -bipyrazine) or bipym (2,2 -bipyrimidine) (Fig. 2), have free non-chelated nitrogen atoms. It has been shown that all these compounds are all more basic in the excited state than the ground state [75,93,94], so that the excited states are already protonated at pH 5-6 on the non-chelated nitrogen atoms. 

Interestingly, the correlation of the luminescence quenching by the mononucleotides and polynucleotides with the occurrence of a photoelectron transfer process examined by flash photolysis, has been found [73,95] for the whole series of Ru(II) complexes with TAP and HAT ligands discussed in Sect. 4.1. As will be developed in Sect. 5., this photoelectron transfer with polynucleotides is also connected to enhanced yield of strand breaks and the appearence of adducts on DNA. 

An anion exchange resin (e.g. Amberlite R-120) was treated with protonated dithiooxamine, H2NC(S)C(S)NH2 Using the supported ligand, quantitative removal of copper, cadmium, and lead ion solutions at neutral or slightly alkaline solutions of deionized or tap water, but poor results were obtained with sea water [22]. 

In this section we will consider several complexes. The particular systems that were investigated are composed of a central metal ion M (M=Zn2+, Mg2+, or Ni2+) with porphyrin (P), tetra-phenylporphyrin (TPP), tetraazoporphyrin (TAP), or phthalocya-nine (Pc) as the ligand. The absorption and MCD spectra of the porphyrin and TPP complexes are sufficiently similar to each other that they can be discussed together. The review of the TAP and Pc results will be presented later. 

Meek and co-workers reported nickel complexes with the ligands qas (LII), tap (im) and tasb (LIV) where the terminal AsMe2 groups are joined to the apical donor (As, P, Sb) by trimethylene chains.1412-1414 1415 Most of the complexes have the usual formula [NiXLJY, and... 

Martell and Calvin588 have summarized the pioneering studies of Mann and Pope, using tap (36) as a stereochemical probe in Pt11 chemistry and ML3+ (M = Co, Rh L = tap) have been prepared.583,584 The other tripodal ligands have been used more frequently in stability constant studies and the results have been reviewed.589,590... 

The Ru11 complexes that contain polyaza-aromatic ligands, such as TAP (1,4,5,8-tetra-azaphenanthrene) and HAT (1,4,5,8,9,12-hexa-azatriphenylene) manifest the very high oxidation potential of their 3MLCT states. Therefore, under illumination, they are able to abstract an electron even from rather poor electron donors, eg biopolymers such as DNA, oligonucleotides, and oligopeptides. Other effects of the photoinduced electron transfer may be photoadduct formation and photocrosslinking via metal complexes [102],... 

Blasius R, Moucheron C, Kirsch-De Mesmaeker A. Photoadducts of metallic compounds with nucleic acids - role played by the photoelectron transfer process and by the TAP and HAT ligands in the Ru11 complexes. Eur J Inorg Chem 2004 3971-9. 

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