Oxygen and other Donor Atoms

Complexes with Oxygen and Other Donor Atoms. The crystal structure of the 4-phenylpyridine adduct of [VO(acac)2] has shown that the molecule adopts an approximately cis-octahedral structure (37) with a V=0 bond length of 158(1) pm.  

Nitriloacetic acid reacts with vanadium-(m). -(iv), or -(v) oxides to form oxovanadatranetrionic acid (38). The crystal structure of [VO(CjQHgNO)2] (CjgHgNOH = 2-methyl-8-quinolinol) has shown that the vanadium atom has a five-co-ordinate trigonal-bipyramidal environment, with three oxygen atoms in the equatorial plane and the two nitrogen atoms of the bidentate ligand in the apical positions. The optimum conditions for the formation of a 1 2 2 vanadium(iv)-morin-4-aminoantipyrine system have been described as pH 5, a tenfold excess of morin (39), and a 3300-fold excess of 4-amino-antipyrine.  

Absorption and c.d. spectra of the complex formed between oxovanadium-(iv) and the Schiff base derived from (J )-l,2-propanediamine and two moles of acac indicate that the co-ordinated Schiff base moiety is close to planarity. The lack of spin-spin coupling between metal centres in iViV -propy-lenebis(salicyliminato)oxovanadium(iv) molecules (// = 1.78BM) has been discussed. Some seven new oxovanadium(iv) complexes with iV-(2-hydroxy- 

The new series of oxovanadium(iv) complexes with Schiff bases derived from 2-aminothiophenol and substituted salicylaldehyde (40) or 2-hydroxy-naphthaldehyde has been synthesized and characterized. The ligands (40a), 

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Complexes with Ligands containing Oxygen and other Donor Atoms. The e.s.r. spectra of liquid and frozen solutions of the oxovanadium(iv) monothio-P-diketonates [V0(CH(CSR )C0R2 ] (R R = Me, CF3, Ph, 2-thienyl, or p-naphthyl) have shown that they exist as simple monomers in solution. The formation constants of the 1 1 complex between and thiodiglycol-... 

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