Glyoximato complexes

The preparation of some solvent complexes [Pd(dien)S](C104)2 (S = DMF, DMSO, MeCN, or HjO) [equation (10)] has been described. Attempts to prepare similar Me2CO or THF complexes gave only the aquo species [Pd(dien)(H20)], which reacts further with NaBPh to yield [Pd(dien)Ph]BPh4 and BPha. Different patterns have been observed in the mass spectra of a variety of substituted glyoximato complexes of Ni and Pd depending on the nature of the substituent. ... 

Mixed valence glyoximato-complexes of Pd and Pt have been obtained as diamagnetic black crystals with a metallic lustre by treatment of the glyoximato-metal complex with iodine in dichlorobenzene. The A -ray structure shows that on forming the mixed valence compound, [(C2H3N202)2PdI], the Pd—Pd distance is shortened from 3.558 to 3.244 A. It has also been shown that the metal complexes of Pd, Pt, with... 

Bis(glyoximato)cobalt(II) complexes of the types Co(DH)2B2 and Co(DH)2B2 (DH = disubstituted glyoxime, B = base, e.g. pyridine or triphenylphosphine) reduce benzyl bromide in benzene and acetone solutions ... 

The reactions of several Co(ii) complexes have been examined (Halpern, 1974), namely, pentacyanocobaltate(n) (Chock and Halpern, 1969 Halpern and Maher, 1964, 1965 Kwiatek and Seyler, 1965,1968 Kwiatek, 1967), bis-(glyoximato)cobalt(il) (Schneider et al., 1969), cobalt(li) Schiff s base (Marzilli et al., 1970, 1971) and bis(dioximato)cobalt(ii) (Halpern and Phelan, 1972) complexes. A halogen-atom-transfer mechanism has been proposed for most halides (158, 159), with the exception of the reaction of cobalt(ii) Schiflf s... 

The term cobaloximes refers to that class of cobalt complexes in which two dimethylglyoximato or other glyoximato monoanions occupy four coordination positions about cobalt and in which the four N donors are in essentially the same plane. A neutral octahedral low-spin d6 Co(III) cobaloxime is shown in Figure 1. Cobaloximes with this oxidation state have been studied most extensively since these are more stable than the oxidation state I, II, and IV compounds. The chemistry of these latter oxidation state compounds will be reviewed... 

By using benzylbis(dimethy glyoximato)Co(III) and poly(4-vinylpyridine-co-styrene) in THF it was found that the higher complex formation constant is due to lower complex dissoziation rate constants comparing with low molecular pyridine63. ... 

Allen, F. H., Kennard, 0., and Taylor, R., Systematic analysis of structural data as a research technique in organic chemistry, Acc. Chem. Res., 16, 146-153 (1983). Vranka, R. G., and Amma, E. L., Metal ion-aromatic complexes. II. The crystal structure of the 1 1 silver nitrate-pyrazine complex, Inorg. Chem., 5, 1020-1025 (1966). Kubel, F, and Strahle, J., Crystal structure of polymeric bis(dismethyl-glyoximato)pyrazine iron (II), Z Naturforsch. B, 38, 258-259 (1983). 

The cobalt(ll) species most widely used as catalysts in oxidations by O2 are complexes with salen, porphyrin, phthalocyanine, acac, dimethyl-glyoximato, amine, pyridine, cycKdene and carboxylato Kgands. 

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