Nitroxyl ligand

This is one of the purity assays to which it must be submitted. It is interesting to note that in this particular case, it is not Legal s reaction that occurs. It is rather an exchange reaction of nitroxyl ligand with the p-aminophenol rest ... 

Later even more complexity was demonstrated (Makino et al., 1992) in the reaction between DMPO and Fe111 in water. The HO-DMPO" formed was transformed into a hydroxamic acid [24] which is a tautomer of 2-hydroxy-DMPO [25] in a Fenton system transfer of a hydroxyl (cf. p. 133) from the ligand-FeOOH complex to either of these species leads to additional epr-active nitroxyls [26] and [27] in reaction (72). 

In addition, such chelators, based on the hydroxamic acid bidentate ligand, may diminish the toxic effect of Reactive Oxygen Species (ROS), such as hydroxyl and superoxide radicals, by generating relatively stable nitroxyl radicals. ... 

A Cu(II) complex containing two spin-labelled ligands was prepared with a rigid linkage between the terpyridine chelator and a nitroxyl ring.26 Due to the large anisotropy of the Cu(II) spectrum only a small fraction of the Cu(II) spins are excited by the pulses of a DEER experiment. Analysis of the echo modulation... 

Amongst other N,0-donor ligand systems are worth noting 8-oxyquinoline, 2-hydroxyphenylbenzazoles, and nitroxyl radicals. The first of them, together with its substituted derivatives, forms the well-known ICC 45 [1,8,13,775-778], The ICC of type 446 are characteristic for all 2-hydroxyphenylbenzazole ligands [8,779] ... 

At present, many coordination compounds, which contain ligands capable of participating in easy and reversible one-electron redox processes, are known. Nitroxyl radicals, spatially hindered o-quinones, quinoneimines, and phenoxazinone systems are examples of such ligands. 

X-ray data for coordination compounds of metals with anion ligands based on nitroxyl radicals, derivatives of imidazoline, piperidine, pyrrolidine, and pyrroline 93ZSK119. 

Paramagnetic metal complexes with heterocyclic nitroxyl radicals as ligands 89MI2. 

The [M (por)(aIkyl)] species reveal a very remarkable reactivity toward (TEMPO) and related nitroxyl radicals (M = Rh, Ir, por = TTP, TMP and some less common OMP, BTPP, and BOCP porphyrinato ligands shown in Fig. 53). 

---