Copper acetylacetone

Decomposition of the diazoimide (551) by heating in the presence of copper acetylaceton-ate also generated a ketocarbene (552). This undergoes an intramolecular condensation to give the anhydro-4-hydroxy-3-methyl-4-p-nitrophenyl-2-phenyloxazolium hydroxide (553), which cannot be prepared by more classical means (75CL499). 

Deposition occurs at much lower temperature (260-340°C) by the decomposition of metallo-organic compounds such as copper acetylacetonate, Cu(C5H202)2 or by the hydrogen reduction of the copper chelate, Cu(C5HFg02)2 at and more recently of... 

We synthesized uniform CU2O coated Cu nanoparticles from the thermal decomposition of copper acetylacetonate, followed by air oxidation. We successfully used these nanoparticles for the catalysts for Ullmann type amination coupling reactions of aryl chlorides. We synthesized core/shell-like Ni/Pd bimetallic nanoparticles from the consecutive thermal decomposition of metal-surfactant complexes. The nanoparticle catalyst was atom-economically applied for various Sonogashira coupling reactions. 

Section B gives some examples of metal-catalyzed cyclopropanations. In Entries 7 and 8, Cu(I) salts are used as catalysts for intermolecular cyclopropanation by ethyl diazoacetate. The exo approach to norbornene is anticipated on steric grounds. In both cases, the Cu(I) salts were used at a rather high ratio to the reactants. Entry 9 illustrates use of Rh2(02CCH3)4 as the catalyst at a much lower ratio. Entry 10 involves ethyl diazopyruvate, with copper acetylacetonate as the catalyst. The stereoselectivity of this reaction was not determined. Entry 11 shows that Pd(02CCH3) is also an active catalyst for cyclopropanation by diazomethane. 

Yanez et al. reported the synthesis of miconazole and analogs through a carbenoid intermediate. The process involves the intermolecular insertion of carbe-noid species to imidazole from a-diazoketones with copper acetylacetonate as the key reaction of the synthetic route [11]. 

The reaction of olefin epoxidation by peracids was discovered by Prilezhaev [235]. The first observation concerning catalytic olefin epoxidation was made in 1950 by Hawkins [236]. He discovered oxide formation from cyclohexene and 1-octane during the decomposition of cumyl hydroperoxide in the medium of these hydrocarbons in the presence of vanadium pentaoxide. From 1963 to 1965, the Halcon Co. developed and patented the process of preparation of propylene oxide and styrene from propylene and ethylbenzene in which the key stage is the catalytic epoxidation of propylene by ethylbenzene hydroperoxide [237,238]. In 1965, Indictor and Brill [239] published studies on the epoxidation of several olefins by 1,1-dimethylethyl hydroperoxide catalyzed by acetylacetonates of several metals. They observed the high yield of oxide (close to 100% with respect to hydroperoxide) for catalysis by molybdenum, vanadium, and chromium acetylacetonates. The low yield of oxide (15-28%) was observed in the case of catalysis by manganese, cobalt, iron, and copper acetylacetonates. The further studies showed that molybdenum, vanadium, and... 

Similar to chemical vapor deposition, reactants or precursors for chemical vapor synthesis are volatile metal-organics, carbonyls, hydrides, chlorides, etc. delivered to the hot-wall reactor as a vapor. A typical laboratory reactor consists of a precursor delivery system, a reaction zone, a particle collector, and a pumping system. Modification of the precursor delivery system and the reaction zone allows synthesis of pure oxide, doped oxide, or multi-component nanoparticles. For example, copper nanoparticles can be prepared from copper acetylacetone complexes [70], while europium doped yttiria can be obtained from their organometallic precursors [71]. 

A report (18) by Djordjevis, Lewis, and Nyholm in 1959 that reaction of copper acetylacetonate with N204 afforded bis-(3-nitro-2,4-pentanediono)copper-(II) (V), spurred our early efforts in acetylacetonate chemistry. The nitro-chelate was thoroughly characterized. 

Although the halogenated chelates of chromium, cobalt, and rhodium would be difficult to prepare from the sensitive 3-halo-2,4-pentanediones, the copper (II) bromochelate was synthesized both from the bromodiketone and by direct bromination of copper acetylacetonate. The relatively labile copper chelates form much more rapidly than the kinetically stable chelates of chromium, cobalt, and rhodium. 

Reaction with 1,2-Propanediamine. Following the general procedure only copper acetylacetonate was obtained. Using a large excess of the diamine, a trace of the desired product was obtained. 

The planar configuration of quadricovalent copper(Il) was discovered by Cox and Webster21 in the compounds of copper with 0-dike-tones (copper disalicyl ldoxime, copper acetylacetonate, copper ben-zoylacetonate, the copper salt of dipropionylmethane) and by Tunell, Posnjak, and Ksanda22 in the mineral tenorite, CuO. In crystalline cupric chloride dihydrate (Fig. 5-9) there are molecules with the planar configuration23... 

The Reaction between Selenium Tetrachloride and Copper Acetylacetone. 

The formation of diselenium fo sacetylacetone from selenium monochloride and copper acetylacetone in molecular proportions may be expressed as follows ... 

The Ms-compound also arises to a small extent in the condensation of copper acetylacetone with selenium tetrachloride. 

Dry copper acetylacetone, 25 1 grams, is added during 15 minutes to 21 2 grams of selenium tetrachloride suspended in 100 c.c. of chloroform... 

Precisely the last condition explains the fact that mainly ICC have been obtained by the immediate interaction of ligands and zero-valent metals. Thus, a large series of metal p-diketonates was synthesized in the absence of a solvent [513,634-638], for example, iron bis- and tra-acetylacetonates [635]. It was shown that other ligands can serve as activators or promoters in these processes. In particular, the introduction of a,a or y,y -bipy into the reaction mixture gives the possibility of isolating copper acetylacetonates and adducts of similar complexes of cobalt and nickel [636], meanwhile the p-diketonates of the metals above are not formed under conditions similar to those reported in Ref. 635. Under dissolution of more active metallic barium in the mixture of another p-dikctone - dipivaloyl-methane (DPM) - with dyglime (DG) or tetraglime (TG) in absolute pentane, the mononuclear complex [Ba(DPM)2(TG)] and binuclear complex [Ba2(DPM)4 ( t-H20)(DG)] were isolated and structurally characterized [637]. 

Reaction of heteroaromatic thioketones 638 with the carbenoids, generated from phenyliodonium bis(phenylsul-fonyl)methane or bis(arylsulfonyl)diazomethanes in the presence of a copper acetylacetonate catalyst, affords heterocycle-fused [c]thiophenes 639. The reaction involves ring closure of the intermediary thiocarbonyl ylides and elimination of a sulfenic acid (Equation 33) <1995S87>. 

Homopolynuclear copper acetylacetonate complexes containing phen or bipy bridges play an important role in sustaining supramolecular solid-state architectures. A group of... 

Ru(acac)s Si02. The differences discussed here for the IR spectra of the supported and supported copper acetylacetonate complex are not observed in... 

Mitchell, Mark B., Vasumathi R. Chakravarthy, and Mark G. White, Interaction of Single and Multiple Layers of Copper Acetylacetonate [Cu(II)(acac)2] Complexes with Silica Surfaces An Infrared Diffuse Reflectance Study , Langmuir, 1994, 10 4523-4529. 

Kenvin, J. C. and M. G. White, Selective Chemisorption and Oxidation Reduction Kinetics of Supported CuO Prepared from Copper Acetylacetonates on Cab-O-... 

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