Beta-diketones

Champmartin D and Rubini P 1996 Determination of the 0-17 quadrupolar coupling constant and of the C-13 chemical shielding tensor anisotropy of the CO groups of pentane-2,4-dione and beta-diketonate complexes in solution. NMR relaxation study/norg. Chem. 35 179-83... 

Carbon is alkylated ia the form of enolates or as carbanions. The enolates are ambident ia activity and can react at an oxygen or a carbon. For example, refluxing equimolar amounts of dimethyl sulfate and ethyl acetoacetate with potassium carbonate gives a 36% yield of the 0-methylation product, ie, ethyl 3-methoxy-2-butenoate, and 30% of the C-methylation product, ie, ethyl 2-methyl-3-oxobutanoate (26). Generally, only one alkyl group of the sulfate reacts with beta-diketones, beta-ketoesters, or malonates (27). Factors affecting the 0 C alkylation ratio have been extensively studied (28). Reaction ia the presence of soHd Al O results mosdy ia C-alkylation of ethyl acetoacetate (29). 

GUARESKY - THORPE Pyridone Synthesis Synthesis of pyndones from beta diketones and activated amides... 

Diels-Alder reaction of, 575 electrostatic potential map of, 576 evidence for, 575 structure of, 576 Bergman, Torbern, 2 Bergstrom, Sune K., 1068 Beta anomer, 984 Beta-carotene, structure of, 172 industrial synthesis of, 722 UV spectrum of, 504 Beta-diketone, 851... 

Strontium titanate (SrXi03) by reacting titanium isopropoxide and a strontium beta-diketonate complex at 600-850°C and 5 Xorr. 

Strontium titanate (SrTi03) has a large dielectric constant of 12, and a high refractive index with potential opto-electronic applications. It is deposited by MOCVD from titanium isopropoxide and a strontium beta-diketonate complex at 600-850°C and 5 Torr.t" " ... 

Triphenylformazan behaves as a bidentate ligand forming 2 1 complexes (217) with divalent copper, nickel, and cobalt.377 Formazan metal complexes can be compared to complexes of azo dyes or beta diketones due to structural similarity.301,302 In general, formazan metal complexes have low stability toward acids. However, when electron-donating substituents are added to the aromatic ring, a considerable enhancement in stability is observed. Cationic complexes of type 218 are also known. The complexation of formazan with metal cation can be accompanied by oxidation to the tetrazolium salt and the formation of a complex... 

Kordosky, G. A. Virnig, M. J. Mattison, P. Beta-diketone copper extractants structure and stability. International Solvent Extraction Conference, Cape Town, South Africa, Mar. 17-21, 2002, 360-365. 

For polymeric CSD processes, three classes of metal organic (metallo-organic) compounds are used most often as starting reagents metal alkoxides, metal carboxylates, and metal beta-diketonates. These species differ in their solubility and reactivity, as well as their tendency to react with one another, all of which are factors that may influence starting reagent selection. Representative structures of these classes of precursors are illustrated in Fig. 2.2.8... 

M. Okumura, K. Tanaka, A. Ueda, and M. Haruta, The reactivities of dimethylgold(lll)beta-diketone on the surface of Ti02—A novel preparation method for Au catalysts. Solid State Ionics 95(1-2), 143-149 (1997). 

Kadutskii AP, Kozlov NG (2006) A novel three-component reaction of anilines, formaldehyde and beta-diketones simple synthesis of 3-spirosubstituted 1,2,3,4-tetrahydroqumo-lines. Synlett 3349-3351... 

Beta-diketone hydrolase Oxidised poly(vinyl alcohol) hydrolase, oxiPVA hydrolase, OPH, OPH hydrolase, BDH pvaB, bdh, oph... 

Grogan G (2005) Emergent mechanistic diversity of enzyme- catalyzed beta-diketone cleavage. Biochem J 388 721-730... 

NT522 Matsuzaki, T. and A. Koiwai. Antioxi-dative beta-diketones in stigma lipids of tobacco. Agr Biol Chem 1988 52(9) 2341-2342. 

Otway DJ, Rees WS (2000) Group 2 element beta-diketonate complexes, synthetic and structural investigations. Coordination Chemistry Reviews 210, 279-328... 

Tiitta M, Niinisto L (1997) Volatile metal beta-diketonates, ALE and CVD precursors for electrolimiinescent device thin films. Chemical Vapor Deposition 3(4), 167-182... 

Sato, S. Wada, M. Relations between intramolecular energy transfer efliciences and triplet energies in rare earth beta-diketone chelates. Bull. Chem. Soc. Japan 1970, 43,1955. 

Chelating extractants such as beta-diketones, tropolones, hydroxyoximes, and 8-hydroxyquinolines (Figure 2.1), have been used extensively for the extraction of actinide ions from moderate to weakly acidic solutions (15-17). Beta-diketones such as acetylacetone (acac), HTTA, benzoyl trifluoroacetone (BTFA), and dibenzoyl-methane (HDBM) have been commonly used for the separation of actinide ions. The extraction mechanism involved formation of the enol form of the beta-diketone prior to complexation and extraction of the metal ion (Figure 2.2). 

FIGURE 2.3 Structures of some beta-diketones used for the extraction of actinides. 

Two-phase Extraction Constants for Actinides with Several Beta-Diketones... 

Ternary Adduct Formation Constants of Early Actinide Ions with some Beta-Diketones... 

Bhattacharyya, A. Banerjee, S. Mohapatra, P.K. Basu, S. Manchanda, V.K. Extraction of ternary beta-diketonates of uranyl ion using some substituted monoamides, Solvent Extr. Ion Exch. 21 (2003) 687-705. 

Manchanda, V.K. Subramanian, M.S. Infrared and P.M.R. investigations of some complexes of uranyl beta diketonates with methyl substituted pyridine N-oxides, Aust. J. Chem. 27 (1974) 1573-1577. 

Robards, K., Patsalides, E., and Dilli, S., Review gas chromatography of metal beta-diketonates and their analogues, J. Chromatogr., 41, 1, 1987. 

Koen Birmemans, Rare-earth beta-diketonates 107... 

Swarts JC, Vosloo TG, Cronje SJ, Du Plessis WC, Van Rensburg CEJ, Kreft E, Van Lier JE (2008) Cytotoxicity of a series of ferrocene-containing beta.-diketones. Anticancer Res 28 2781-2784... 

Complex compounds Beta diketones, CO, A1C13 Fused silica, glass... 

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