Pentane-2,4 dionato

Af-methylsalicylaldiminato, 4,908 pentane-2,4-dionato, 4,908 trifluoroacetato, 4,908 bridged, 4,908-911 cupferron, 2, 512 dinitrogen, 4, 919 binuclear, 4,920 four-coordinate... 

All complexes containing the W02 structural unit have cis configuration and exhibit two strong IR absorption bands around 950 and 900 cm"1. The structure of dichloro-dioxo-pentane-2,4-dionato WV1 has been determined and it contains the expected cis arrangement of the oxygen atoms with a W—O, distance of 1.730 A.61 Table 3 lists well-characterized compounds containing the W02 structural unit. 

The complex bis(pentane-2,4-dionato)-jLi,/i. -dimethoxy-dicopper(II) has been found to be a very effective and selective catalyst for ester exchange of both 2-ethoxycarbonylpyridine and ethyl 2-pyridylacetate to give the corresponding methyl esters.491... 

More sophisticated mass spectrometric methods have been found in the electrospray (ES-MS) and plasma desorption (PD-MS) techniques which have successfully been applied directly to nonvolatile pteridines. A small peak can be detected with folic acid at m/z = 441 together with the mono-, di-, and trisodium species. The dihydro- and tetrahydro derivatives also give the expected results <83Mi 718-05). Fast atom bombardment (FAB) works also with folic acid in special matrices and is another tool for structural studies <83MI 718-08). Even in a molar mixture of 5-methyl-5,6,7,8-tetrahydropterin and tris(pentane-2,4-dionato)iron(III), the metal-pterin complex could be detected by ES-MS <92HCA1955>. 

The pentan-2,4-dionato (acac) complexes may be prepared either by cleaving dinuclear pentan-2,4-dionato complexes with tertiary phosphines,60,61 or by displacing the halo ligands in bridged,... 

Rhodium(III) complexes typically contain anunine, halo, or aqua ligands, or the important bidentate ligands 1,2-diaminoethane (en), oxalato, or pentane-2,4-dionato (acac) and are invariably octahedral. Their wide variety is in part a reflection of the slow reactions, which take place at the low-spin d centers, which allow many intermediates, and geometrical or chiral isomers, to be isolated. It is fairly difficult to oxidize rhodium(III) complexes, but they may be reduced to rhodium(l) species in the presence of suitable ligands. However, there is little current work being carried out on the classical rhodium(III) complexes and even less on the higher oxidation states. 

Aniline and the fluoroanilines exhibit, 4N contact shifts in the presence of (pentane-2,4-dionato) nickel(II). By comparing the shifts with spin densities calculated by the INDO molecular orbital procedure a structure is proposed for the complexes formed in solution. (137) Contact shifts have also been reported from the 14N spectra of some cobalt(II) nitrate complexes. (138) In the case of [Co(H20)5N03] the chemical shift of the nitrate ligand is reported to be 2360 100 ppm to high frequency of the free nitrate ion. (222)... 

Synonyms Cr(acac)3 Tris(pentane-2,4-dionato)chromium... 

Synonyms Bis(1,1,1,6,6,6-hexafluoro pentane-2,4-dionato)copper hydrate Cu(hfa)2H20... 

Reduction of bis(pentane-2,4-dionato)ethylenediaminecobalt(iii) by chromium(ii) occurs by an inner-sphere path involving both singly bridged and doubly bridged transition states, in addition to the expected outer-sphere path. From the crystal structure of (-I- )5g9-oxalatobis(ethylenediamine)cobalt(iii) hydrogen-d-tartrate monohydrate it was found that the optically active complex is locked by the (H-d-tartrate) units of the right-handed spiral chain structure along the b-axis. ... 

In contrast, when pentan-2,4-dione was allowed to react with 3a under similar conditions, chelated pentan-2,4-dionato complex 9 was obtained in which one of four phosphorus atoms of the framework is dissociated. This result of the unique reaction was confirmed by the X-ray structure analysis of the complex 9. Although the explanation of these results obtained for two types of )9-dicarbonyl compounds, malonate and pentan-2,4-dione, is not straightforward at present, the difference in the steric congestion between two dicarbonyl compounds seems to be responsible. 

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