Hydroxylamido complexes

The chemical and structural relationships between hydrazine and hydrazido complexes and between hydroxylamine and hydroxylamido complexes have been recently reviewed.510... 

Some simple oximes have been shown to act as N—O bidentates by side-on coordination of the oxime groups alone. The reaction of acetone with a hydroxylamido complex of molybdenum results in this bonding form for 2-propanone oxime.64,243 The N—O and C—N bond lengths indicate single and double bond character respectively. The reaction was related to the prebiotic formation of HCN from formaldehyde and hydroxylamido-Mo chelates. A similar form of bonding for this ligand was concluded with some fluorotungstate(IV) complexes.65... 

Hydroxylamido complexes, 101 Hydroxylamine, N.N-di-f-butyl-metal complexes, 798 Hydroxylamine, N,N-diethyl-metal complexes, 798 Hydroxylamine, N-methyl-metal complexes, 798... 

Hydroxygermanes, deprotonation, 3, 713—714 r -Hydroxylamido complexes, with mono-Cp Ti(IV),... 

Reaction of the hydroxylamido complexes [M0O2 (ONR2)2] (R = Et, Bz) with B(C6p5)3 gave the pseudo-octahedral species [MoO OB(C6F5)3 (ONR2)2]. 

Hydroxylamido complexes, MoOS(R2NO)2, were first reported in 1981 by Wieghardt and co-workers (176,177). Since then a number of reports describing alternative syntheses, and chemical, spectroscopic, electrochemical, and structural properties have appeared (178-181). 

An unusual 18e seven-coordinate Mo(II) hydroxylamido complex [Mo(K -N,0-H2NO)(Tp )I(NO)] has a distorted pentagonal bipyramid structure with equatorial K -NH20 ligand. In the solid state, it exists as a dimer due to the formation of two NH--0 hydrogen bonds between the adjacent NH20 ligands (Scheme 18). ... 

Table 5. Selected bond length and angles for [VO(dipic)(Me2NO)(H2O)].0.5H2O and other known seven-coordinate dipicolinato-vanadium(V) complexes with ternary peroxo or hydroxylamido ligands.

The reaction of Mo02(MeNHOi2 in the presence of the hydroxylamine ligand and CS2 proceeds according to Scheme 4. 4 The resultant formally seven-coordinate complex has a distorted pentagonal bipyramidal structure with the lone oxo group in the apical position. The five equatorial positions are occupied by two formally bidentate 0,N hydroxylamido ligands of... 

Fiala (45) and Fiala and Burk (46) early postulated, by analogy from the visible absorption spectra of iron transferrin and the iron complex of aspergillic acid, that iron was bound in transferrins through a hydroxamic acid-CC>2 complex. This formulation is shown in Fig. 15. Fraenkel-Conrat (48), however, could find no evidence for hydroxylamido groups in chicken ovotransferrin. He also prepared and studied the properties of several hydroxylamido proteins by the chemical introduction of the hydroxylamido groups, and found that their properties were quite different from those of the transferrins. 

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