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The authors study Raman scattering and FTIR absorption spectra of pure acetylacetone and aqueous solutions of it at room temperature and atmospheric pressure. Results from experiments and calculations show that a red shift of the C=O stretching vibrational band and a blue shift of the C–H stretching vibrational band are observed when the amount of acetylacetone in a solution is reduced. The distribution of potential energy is analyzed for the monomeric molecule of the keto form of acetylacetone. The calculated and observed frequencies of vibration are in good agreement. It is shown that acetylacetone creates molecular clusters with water molecules in the form of C=O...H and C–H...O hydrogen bonds, altering the shape of the spectral bands. [ABSTRACT FROM AUTHOR]

The crystal and molecular structures of the complex [99TcCl(CO)3(C5H8O2)]2 (C5H8O2 = Hacac = acetylacetone) formed in the course of prolonged standing of a [99Tc(acac)(CO)4] solution in ССl4/CDCl3 and of its analog containing no organic ligand, [99TcCl(CO)4]2, were determined. Both complexes contain a [Tc2(μ-Cl)2] four-membered ring. The remaining sites in the coordination sphere of the Tc atom are occupied by carbonyl ligands, and in the case of [99TcCl(CO)3(Hacac)]2, also by the neutral acetylacetone molecule in the enol form. The Hacac molecules in the binuclear complex are in the cis position to the Cl atoms in the octahedral surrounding of the Тс atoms and in the trans position to each other relative to the [Tc2(μ-Cl)2] ring. A comparative analysis of the geometries of the complexes and their known analogs was performed. [ABSTRACT FROM AUTHOR]

The radiolysis of liquid and boiling hexafluoroacetylacetone has been studied. The structure of the main radiolysis products indicates the predominance of C–CF3 and C–F bond cleavages. Ten compounds including monoketones, trifluoroacetic acid, keto alcohols, and tautomeric tetraketones were formed. Carbon monoxide was the main gaseous product, and its yield increased under boiling conditions. The initial yields of hexafluoroacetylacetone degradation were 0.29 ± 0.2 and 0.32 ± 0.2 µmol/J at 293 and 343 K, respectively. No accumulation of free HF was observed at low doses. The products of radiolysis are less diverse than those in acetylacetone; this is due to enhancement of the cage effect and to an increase the Onsager radius and the ability of trifluoromethyl groups to dissipate excitation energy. [ABSTRACT FROM AUTHOR]

The crystal and molecular structures of the complex [99TcCl(CO)3(C5H8O2)]2 (C5H8O2 = Hacac = acetylacetone) formed in the course of prolonged standing of a [99Tc(acac)(CO)4] solution in ССl4/CDCl3 and of its analog containing no organic ligand, [99TcCl(CO)4]2, were determined. Both complexes contain a [Tc2(μ-Cl)2] four-membered ring. The remaining sites in the coordination sphere of the Tc atom are occupied by carbonyl ligands, and in the case of [99TcCl(CO)3(Hacac)]2, also by the neutral acetylacetone molecule in the enol form. The Hacac molecules in the binuclear complex are in the cis position to the Cl atoms in the octahedral surrounding of the Тс atoms and in the trans position to each other relative to the [Tc2(μ-Cl)2] ring. A comparative analysis of the geometries of the complexes and their known analogs was performed. [ABSTRACT FROM AUTHOR]

The reactions of purine nucleic base perchlorates with the simplest 1,3-diketone – acetylacetone – were studied for the first time. It was demonstrated that adenine reacts with acetylacetone in a 1:2 molar ratio via opening of the pyrimidine fragment of the bicyclic struc- ture, elimination of a one-carbon fragment in the form of a formic acid molecule, and recyclization into 8-(4,6-dimethylpyrimidin-2-yl)- 2,4-dimethylimidazo[1,5-a]pyrimidine. Guanine, in turn, reacted with acetylacetone in a 1:1 ratio and formed 7,9-dimethyl-3H-pyrimido- [2,1-b]purin-10-ium-4-olate. In this case, the direction of heterocyclization differed from that observed in the reaction of guanine with malondialdehyde during the in vitro and in vivo formation of the minor nucleotide base M1G. The synthesized compounds were capable of causing single-strand breaks in DNA macromolecules. [ABSTRACT FROM AUTHOR]

A novel access to pyrrolo[3,4-d]pyrimidine scaffold via tandem Staudinger/intramolecular aza-Wittig reaction of 5-acyl-4-(1-azidoalkyl)-3,4-dihydropyrimidin-2(1H)-ones promoted by PPh3 was developed. Synthesis of the starting pyrimidinones involved the reaction of readily available N-[(2-azido-1-tosyl)alkyl]ureas with Na enolates of benzoylacetone or acetylacetone followed by acid-catalyzed dehydration of the resulting products without their isolation. [ABSTRACT FROM AUTHOR]

An effective one-pot three-component protocol for the synthesis of polysubstituted thiazole derivatives is reported. The reaction proceeds between arylglyoxals, thiosemicarbazones, and acetylacetone or ethyl acetoacetate in ethanol as solvent and in the presence of acetic acid as catalyst. [ABSTRACT FROM AUTHOR]

A new coordination polymer, {[Zn2(L)2(TDC)2]·H2O}n (1) (L = 1,4-bis(1H-benzimidazol-2-yl)butane, H2TDC = 2,5-thiophenedicarboxylic acid), was hydrothermally synthesized and characterized. 1 displays a 2D sql network, which extends into a 3D supramolecular network through hydrogen bonding. 1 shows thermal stability when the TGA temperature is below 245 °C and excellent pH stability (3–12). 1 is able to selectively detect acetylacetone and Fe3+ ions, respectively, with recyclability and low detection limits. The luminescence mechanism is analyzed in detail. A new dual-responsive luminescent coordination polymer (CP), {[Zn2(L)2(TDC)2]·H2O}n (1) (L = 1,4-bis(1H-benzimidazol-2-yl)butane, H2TDC = 2,5-thiophenedicarboxylic acid), was hydrothermally synthesized and characterized, which showed good thermal and water stabilities. 1 displays a 2D sql layer and extends into a 3D supramolecular network through hydrogen bonding. 1 is promising a dual-functional luminescent sensor-based CP for detection of acetylacetone and Fe3+ cation with high sensitivity and selectivity. [ABSTRACT FROM AUTHOR]

The spectral luminescence properties of europium(III) extracts with acetylacetone and trialkylbenzylammonium chloride are studied. The possibility of using the luminescence excitation and luminescence spectra to establish the composition of the extracted europium(III) complexes is shown. It is established that the transfer of excitation energy to the europium ion in the extracted complexes may occur from both the acetylacetone and triaklylbenzylammonium levels. The formation of the mixed-ligand complex (taba) [EuCl3(acac)] in the organic phase leads to a synergic effect with an increase in the luminescence intensity of the europium. [ABSTRACT FROM AUTHOR]

Four new ternary Zn(II)-coordination polymers, namely, {[Zn2(TPD)2(L1)2·H2O]·2H2O}n (1), [Zn0.5(TPD)0.5(L2)]n (2), {[Zn1.5(TPD)1.5(L3)]·0.25H2O}n (3) and {[Zn(TPD)(L3)]·2H2O}n (4) (L1 = 1,2-bis(benzimidazol-1-ylmethyl)benzene, L2 = 1,4-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene, L3 = 1,3-bis(1-(pyridin-4-ylmethyl)-1 H-benzimidazol-2-yl)propane, H2TPD = 2,5-thiophenedicarboxylic acid) were hydrothermally/solvothermally synthesized and characterized. 1 and 4 possess a 1D chain structure, 2 is a sql layer and 3 reveals a tfi topological framework. 1–4 reveal excellent thermal stability and can stably exist in acid-base solutions. 1–3 are highly sensitive and selective luminescent sensors for the detecting of acetylacetone, Fe3+ and Al3+ (just 3) ions via the luminescence quenching process. [ABSTRACT FROM AUTHOR]

UV-induced processes are commonly studied in acetylacetone analogues. In this contribution, we revisit the existing work on the photoisomerization process in some of the fluorinated analogues of acetylacetone, i.e., trifluoroacetylacetone (F3-acac) and hexafluoroacetylacetone (F6-acac). We performed selective UV laser excitation of these molecules trapped in soft cryogenic matrices, namely neon and para-hydrogen, and probed by vibrational spectroscopy. Clear spectroscopy of 3 isomers of F6-acac and 6 isomers of F3-acac is obtained, including the first characterization of a second open enol isomer of hexafluoroacetylacetone. In addition, we present the electronic absorption spectra of both molecules in cryogenic matrices before and after specific UV irradiations, giving new data on the electronic transitions of photoproducts. Vibrational and electronic experimental results are analyzed and discussed within comparisons with DFT and TD-DFT calculations. Our findings contribute to a deeper understanding of the photoisomerization process in these molecules after electronic excitation in gas and condensed phase. [ABSTRACT FROM AUTHOR]

A new inorganic-organic hybrid heterometallic compound, namely {[(CH3)2NH2][CdNa(4,4′-bpdc)2]}n·6n(H2O) (1, 4,4′-H2bpdc is 4,4′-biphenyldicarboxylic acid), was synthesized through the solvothermal self-assembly reactions of 4,4′-H2bpdc ligand in combination with Cd(II) and Na(I) salts. importantly, compound 1 shows high selectivity and sensitivity for the detection of acetylacetone (Hacac) molecule with a high Ksv value of 11.667 nM−1. Its prevention activity on osteoarthritis after the reconstruction of anterior cruciate ligament was investigated and the associated mechanism was analyzed. At first, the enzyme linked immunosorbent assay (ELISA) detection was implemented in the current research to detect the Interleukin-1β (IL-1β) and Interleukin-1β (IL-18) content released into joint cavity after treated with the compound. The results showed that this complex was good at inhibiting the IL-1β and IL-18 content released into joint cavity. The real time reverse transcription-polymerase chain reaction (RT-PCR) was carried out and the nuclear factor kappa-B (NF-κB) signaling pathway activation in joint soft tissue was tested exploiting real time RT-PCR. The real time RT-PCR exhibited that the NF-κB signaling pathway activation in the joint soft tissue was significantly reduced by the new compound. Subsequently, the levels of cartilage tissue cell apoptosis were also tested through Annexin V-FITC Apoptosis detection, and the results suggested the cartilage tissue cell apoptosis levels were obviously reduced by the compound. [ABSTRACT FROM AUTHOR]

It has been shown for acetylacetone as an example that the intramolecular hydrogen bond significantly affects the radiolytic transformations of organic compounds by suppressing the proton transfer from the primary radical cation to the molecule and also by promoting cleavage of the C–OH bond in the enol form. Due to these effects, the major heavy product of radiolysis at 295 K is 4-oxopent-2-en-2-yl acetate. Under boiling conditions (413 K), hydrogen bonds are cleaved, resulting in the predominant formation of 4-hydroxy-2-pentanone, which is not detected at 295 K. [ABSTRACT FROM AUTHOR]

Intramolecular hydrogen bonding has a significant effect on the radiolytic transformations of β-diketones. Using the radiolysis of acetylacetone as an example, it has been shown that a hydrogen bond between the hydroxyl and carbonyl in an enol prevents proton transfer from the primary radical cation to the neighboring molecule. As a result, the radiolytic formation of a keto alcohol (4-hydroxy-2-pentanone) was not observed at room temperature, but it was effective under boiling conditions. The intramolecular hydrogen bond contributed to a significant structural stress in the radical cation, which increased the yield of C–OH bond cleavage and the inhomogeneous formation of acetate (4-oxopent-2-en-2-yl acetate) under normal conditions. [ABSTRACT FROM AUTHOR]

The solvated complex [МоО2(L1)]4dimethylformamide (I) was synthesized. Its structure was determined by X-ray diffraction analysis. The crystal structure is composed of the tetranuclear complexes [МоО2(L1)]4 (Ia) as the structural units lying on crystallographic twofold axes. Both crystallographically independent molybdenum atoms are in a distorted octahedral coordination environment formed by two cis-О(oxo) ligands, two N(L1) atoms of two molecules Ia in trans-positions to the О(oxo) ligands, and two О(L1) atoms of one complex molecule in cis-positions to О(oxo) and trans- to each other. Each (L1)2– ligand is coordinated to two Мо atoms in a tetradentate tridentate-chelating (2О, N) bridging (N) mode. The average bond lengths in complex Iа are as follows: Мо–О(oxo), 1.701 Å; Мо–N(L1), 2.460 (b) and 2.214 Å (c); Мо–О(L1), 1.980 Å. The О(oxo)–МоО–(oxo) bond angle is 105.6°. The ordered dimethylformamide molecule is located in a narrow channel in the structure. The strongly disordered (non-located) solvent molecules (methanol/dimethylformamide/water) occupy wide channels in the structure of I. [ABSTRACT FROM AUTHOR]

The reactions of substituted 5-aminopyrazoles and 5-amino-1,2,4-triazole with 3-(ethoxymethylidene)acetylacetone, as well as with ethyl acetylpyruvate sodium salt, were employed to synthesize a number of substituted pyrazolo[1,5-a]- and 1,2,4-triazolo[1,5-a]pyrimidines. The alkylation of the synthesized pyrazolo[1,5-a]- and 1,2,4-triazolo[1,5-a]pyrimidines with methyl iodide and ethyl iodide was studied. Evidence was obtained from the NMR (NOESY) spectra that pyrazolo[1,5-a]pyrimidines are alkylated at the nitrogen atom of the pyrimidine ring, while the alkylation of 1,2,4-triazolo[1,5-a]pyrimidines involves the triazole N3 atom. [ABSTRACT FROM AUTHOR]

A method for the preparation of di- and trifluoromethyl derivatives of pyridines containing a tricyanobutadiene fragment has been suggested. Di- and trifluoromethyl-substituted [3-cyanopyridin-2(1H)-ylidene]malononitriles have been synthesized via reaction of malononitrile dimer with fluorinated acetylacetone derivatives. Optical properties of the obtained compounds in solution and in the solid state have been studied. [ABSTRACT FROM AUTHOR]

The Pt(II) acetylacetonate complex [(L)Pt(Acac)] based on aminophenyl-substituted 2-(2-thienyl)pyridine (L) was synthesized, its photophysical properties were studied and compared with these properties for a similar complex containing no amino group in the ligand. The structure of the complex was confirmed by X-ray diffraction (CIF file CCDC no. 2144689), 1H and 13C NMR spectroscopy, ESI mass spectrometry, and elemental analysis. [ABSTRACT FROM AUTHOR]

It has been established that the reaction of phenylselenyl chloride with diketones having two reaction centers—at the central carbon atom and in the side substituent—leads to the formation of both possible isomers. The reason for this is the isomerization of the initially formed product containing the PhSe group at the central carbon atom, which occurs in the presence of the formed hydrogen chloride. The isomerization is due to the high electrophilic activity of the PhSe group, which is under the action of two adjacent electronoacceptor (carbonyl/carboxyl) groups. Carrying out the reaction under conditions excluding the formation of hydrogen chloride, for example, with sodium salts of diketones, makes it possible to obtain an isomer containing a PhSe group at the central carbon atom, without impurities of the second isomer. [ABSTRACT FROM AUTHOR]

Phosphoryl-substituted cyclopropane derivatives were synthesized by reaction of (1-bromoethenyl)-(diphenyl)phosphine oxide with CH acids such as acetylacetone, ethyl acetoacetate, and diethyl malonate in the presence of sodium hydroxide (reactant ratio 1:2:3) in acetonitrile at room temperature. [ABSTRACT FROM AUTHOR]

In this study, the influencing factors of Hantzsch reaction have been investigated and a simple spectrofluorimetric method for the determination of acyclovir, ganciclovir, famciclovir, oxiracetam, and prazosin hydrochloride developed. The proposed method is based on the Hantzsch reaction of acetyl acetone-formaldehyde reagent with drugs. The results indicate that the drugs fluorescence in H2O is inhibited and enhanced in DMSO. [ABSTRACT FROM AUTHOR]

A series of functionalized 4,5,6,7-tetrahydroindol-4-one derivatives containing a residue derived from β-dicarbonyl compound at position 3 were prepared by a reaction of cyclic enaminones, arylglyoxal hydrates, and β-dicarbonyl compounds. Modification of acetylacetone residue at position 3 of tetrahydroindoles was accomplished by condensation with 1,2- and 1,4-bisnucleophiles. [ABSTRACT FROM AUTHOR]

Titrimetric estimation of Fe(III) in [Fe(acac)3] (acacH = acetylacetone) in percentage and subsequent estimation of acac by subtracting the iron percentage from 100.00 is shown in this article. Moreover, the article demonstrates how these estimations derive the molecular formula of the title complex. [ABSTRACT FROM AUTHOR]

The reaction of β-keto esters or acetylacetone with alkyl azides in the system K2CO3/DMSO proved to be a convenient method of synthesis of tri- and disubstituted 1-alkyl-1H-1,2,3-triazoles. [ABSTRACT FROM AUTHOR]

In this present work, we have studied the effect of organic solvents and acetylacetone (Acac) molar ratio on several properties of TiO2 thin films prepared by pneumatic spray pyrolysis (SP). The TiO2 thin films were characterized by the following techniques including the following: X-ray diffraction (XRD), Raman spectroscopy, Scanning Electron Microscopy (SEM) and UV–visible spectrophotometer. The XRD results showed pure anatase TiO2 thin films with preferential orientation (101) plan, the crystallite size varying between 14.72 and 35.12 nm. The Raman spectroscopy confirmed the formation of the only phase of TiO2 (anatase). The morphological properties were investigated by SEM. The UV–Visible spectrophotometer showed the semiconducting properties of anatase TiO2, and the optical band gap was ranged between 3.17–3.34 eV. The refraction index, the extinction coefficient and the porosity were estimated using transmittance values. The TiO2 thin films have had good properties. They were prepared by low-cost technique, spray pyrolysis, by saving energy and time because the samples were synthesized using air pulverization without using any oxygen sources and without any annealing requires the following: CVD room, low pressure and more time for annealing (Sahoo et al. 2019 in Phys Chem Chem Phys 21: 6198–6206). [ABSTRACT FROM AUTHOR]

The reaction of aromatic aldehydes with malononitrile, ethyl or butyl cyanoacetate and acetylacetone in the presence of NaOH under mild conditions (EtOH, 25°C) led to the formation of new series of (1S,5R,6R,9R)/(1R,5S,6S,9S)-2-amino-6,9-diaryl-7-acetyl-8-methyl-4-oxo-5-cyano-3-azabicyclo[3.3.1]nona-2,7-diene-1-carboxylic acids esters. A plausible mechanism of the cascade reaction was proposed. [ABSTRACT FROM AUTHOR]

A three-component reaction of 5-aminotetrazole with aromatic aldehydes and acetylacetone under solvent- and catalyst-free conditions at a temperature of 150–160°С proceeds with the formation of (E)-5-arylvinyl-7-methyltetrazolo[1,5-a]pyrimidines. 5,7-Dimethyltetrazolo[1,5-a]pyrimidine is formed as a side-product of the reaction. [ABSTRACT FROM AUTHOR]

The reaction of acetylacetone with 6-sulfanylhexanoic and 11-sulfanylundecanoic acid hydrazides was used to develop a method for the synthesis of previously unknown 1-(ω-sulfanylacyl)-3,5-dimethylpyrazoles as promising coligands for preparing gold glyconanoparticles for biomedical purposes. [ABSTRACT FROM AUTHOR]

A heteroligand complex of gadolinium stearate with acetylacetone is synthesized. Its composition is determined via thermogravimetry and energy dispersive analysis. Scanning electron microscopy shows that the synthesized material consists of layered particles with an average size of 50–60 μm. According to data from X-ray phase analysis, the complex of gadolinium stearate with acetylacetone has a tetragonal crystal lattice with parameters a = b = 24.03 Å and c = 27.81 Å. Diffuse light reflectance spectra of the complex are used to determine its band gap (3.04 eV). The magnetic susceptibility of the complex in the 2 MHz–2.5 GHz range is calculated from the experimentally measured impedances using a vector network analyzer. [ABSTRACT FROM AUTHOR]

4-(N-Boc-amino)-1,2,3-triazole-5-carbaldehydes upon heating under reflux in acetic acid in the presence of pyrrolidine react with cycloalkanones, acetylacetone, 1,3-cyclohexanediones, and malononitrile resulting in annulation of the pyridine ring with the formation of new derivatives of [1,2,3]triazolo[4,5-b]pyridine. [ABSTRACT FROM AUTHOR]

A cluster of 10 vanadium (5+) atoms bridged by 22 oxygen atoms and having six of the vanadiums around the periphery each bound to a single bidentate acetylacetone is described. This material has no unpaired electrons since V(5+) is 3do. [ABSTRACT FROM AUTHOR]

A multicomponent reaction of arylglyoxal hydrates, acetylacetone or acetoacetic ester, aniline or its 3(4)-substituted analogs in 1:1:2 ratio occurred upon stirring in methanol, giving 4-arylamino-5-hydroxypyrroline derivatives containing 4,5-dihydroxypyrrolines as impurities. [ABSTRACT FROM AUTHOR]

The method of synthesis of fused thiopyridines via S-alkylation of the corresponding pyridine thiones with propargyl bromide has been elaborated. Fused enol tautomers have been obtained via the reaction of the prepared thiopropargyl pyridine compounds with acetylacetone in the presence of mercury(II) acetate followed by the reduction of intermediate organomercury compounds with alkali solution of sodium borohydride. Neurotropic activity of the synthesized compounds has been studied, and compounds with pronounced anticonvulsant activity have been identified. [ABSTRACT FROM AUTHOR]

The alkylation of cyanothioacetamide with benzyl chloride in DMF in the presence of 10% aqueous potassium hydroxide afforded 2,3-bis[amino(benzylsulfanyl)methylidene]butanedinitrile. Analogous reaction with addition of acetylacetone or its 3-methyl derivative led to the formation of 2-benzylsulfanyl-4,6-dimethylor -4,5,6-trimethylpyridine-3-carbonitrile. [ABSTRACT FROM AUTHOR]

Abstract—: Al- and Zr-containing sols intended for producing Al2O3 and ZrO2 nanocoatings, respectively, were prepared by a sol-gel process using N,N-dimethyloctylamine (DMOA) and acetylacetone (acacH). Aluminum and zirconyl nitrates were used as metal precursors. The DMOA/Al and DMOA/Zr molar ratios were 1 and 2, respectively, and the acacH/DMOA molar ratio was 1.5 in both cases. The sols were synthesized at a temperature of 80-90°C and then were evaporated at 90-95°C to a gel state. The resultant gels were characterized by differential thermal analysis, differential scanning calorimetry, and electron impact mass spectrometry. Measurements in the temperature range 20-500°C in air and Ar showed that the Zr-containing material was more thermally stable (decomposition temperature of 304-308°C) than its Al-containing analog (decomposition temperature of 225-230°C). According to the mass spectrometry analysis data, the gels contained metals as acetylacetonate complexes having strong M-O bonds and coordinated molecular DMOA. The nature of the metal was shown to influence both the thermal stability of the gel in which it is present in a chemically bound state and the mechanisms of the processes involved in its thermolysis. [ABSTRACT FROM AUTHOR]

Al-doped ZnO (AZO) powders were prepared by using metal chloride precursors and the sol-gel technique. IR peaks observed at 1590 cm-1 and 1620 cm-1 indicated the formation of metal chelate as a consequence of the addition of acetylacetone to the metal chloride solution. TG-DSC analysis of the AZO gels confirmed the formation of metal chelate as evidenced by the development of several weight loss peaks accompanied by the introduction of new endothermic peaks. The resulting AZO gels were annealed at 500, 600, and 800 °C to study the effect of annealing temperature. XRD and SEM results showed that crystallization of AZO gels takes place around 600 °C. Hexagonal wurtzite structure was identified as the main phase for all the samples. In addition, small shift of the XRD (002) peak coupled with XPS results from the AZO powders confirmed the successful doping of the ZnO powders. Micron sized rod-like AZO powders were uniform in dimension and morphology and remained stable even at 800 °C. [ABSTRACT FROM AUTHOR]

The reaction of malononitrile with acetylacetone in alkaline medium afforded a mixture of 2-amino-4,6-dimethylbenzene-1,3-dicarbonitrile and 4,6-dimethyl-2-oxo-1,2-dihydropyridine-3-carbonitrile, whereas only the latter was formed in alcoholic medium in the absence of a catalyst. The alkylation of 4,6-dimethyl-2-oxo-1,2-dihydropyridine-3-carbonitrile with allyl bromide gave a mixture of N- and O-allyl derivatives. [ABSTRACT FROM AUTHOR]

5-Aryl-2-furaldehydes, obtained by furfural arylation with arenediazonium salts, react with ethyl acetoacetate or acetylacetone and (thio)-urea in the presence of FeCl3·6H2O as a catalyst. A series of ethyl 4-(5-aryl-2-furyl)-6-methyl-2-oxo(thioxo)-1,2,3,4-tetrahydropyrimidine-5-carboxylates was obtained. [ABSTRACT FROM AUTHOR]

This study presents computational fluid dynamics (CFD) simulation of dispersion-free liquid-liquid extraction of copper(II) with trifluoroacetylacetone (TFA) in hollow fiber membrane contactor (HFMC). Mass and momentum balance Navier-Stokes equations were coupled to address the transport of copper(II) solute across membrane contactor. Model equations were simulated using COMSOL Multiphysics™. The simulation was run to study the detailed concentration distribution of copper(II) and to investigate the effects of various parameters like membrane characteristics, partition coefficient, and flow configuration on extraction efficiency. Once-through extraction was found to be increased from 10 to 100% when partition coefficient was raised from 1 to 10. Similarly, the extraction efficiency was almost doubled when porosity to tortuosity ratio of membrane was increased from 0.05 to 0.81. Furthermore, the study revealed that CFD can be used as an effective optimization tool for the development of economical membrane-based dispersion-free extraction processes. [ABSTRACT FROM AUTHOR]

Abstract: In this review, we discuss the nature and bonding, role of metal acetylacetonates as precursors for nanoparticle research, polymer science, catalysis and their mechanistic aspects, which we believe to provide an illustrative overview of current research directions in this rapidly developing field. The chosen examples within this review reflect the remarkable broadness of nanoparticle research, polymer and applications of metal acetylacetonates as catalysts in organic syntheses. The purpose of this review is to provide recent advancements of several catalytic reactions employing well defined metal enolate complexes. Metal enolates are used in a plethora of catalysed reactions. Several catalytic reactions have been highlighted in this review to show where metal enolate complexes have played a significant role in recent years. The ultimate goal of this effort is towards the development of catalysts that impart the selectivities, reactivity, and atom economy needed for cost-effective approaches to a variety of critical chemical transformations.Graphical Abstract: [ABSTRACT FROM AUTHOR]

The formation conditions and luminescence of Tb(III) complexes with synthesized copolymers of unsaturated acetylacetone derivatives with styrene and methyl methacrylate were studied. The luminescence intensity of these Tb(III) complexes was found to depend on the β-diketone substituent nature (CH3, CF3, C6H5) and structure (linear, branched) and the β-diketone to monomer ratio in the polymerizing mixture. [ABSTRACT FROM AUTHOR]

New Cu(II) and Pd(II) complexes of tetradentate macrocyclic nitrogen ligand i.e. (10E,13E)-11,13-dimethyl-4H-dibenzo[g,n]naphtho[1,8-bc][1,5,9,13]tetraazacyclohexa-decine 5,19(12H,20H)-dione have been synthesized. The compounds have been characterized by elemental analyses, spectral (IR, UV-Vis, H NMR, MS and ESR), 3D molecular modeling, molar conductivity, magnetic as well as thermal analysis measurements. On the basis of above studies, tetragonally distorted octahedral or square planar geometry has been proposed for the complexes. Also, the in vitro antitumor activity of the synthesized ligand and most complexes against human breast and human hepatocarcinoma cell lines (MCF-7 and HepG2, respectively) has been studied. Furthermore, the current compounds have been screened for their possible antimicrobial activity against Staphylococcus aureus as Gram-positive bacteria, Escherichia coli as Gram-negative bacteria Aspergillus flavus and Candida albicans as antifungal agents. [ABSTRACT FROM AUTHOR]

The first steps in photochemical processes, such as photosynthesis or animal vision, involve changes in electronic and geometric structure on extremely short time scales. Time-resolved photoelectron spectroscopy is a natural way to measure such changes, but has been hindered hitherto by limitations of available pulsed light sources in the vacuum-ultraviolet and soft Xray spectral region, which have insufficient resolution in time and energy simultaneously. The unique combination of intensity, energy resolution, and femtosecond pulse duration of the FERMI-seeded free-electron laser can now provide exceptionally detailed information on photoexcitation–deexcitation and fragmentation in pump-probe experiments on the 50-femtosecond time scale. For the prototypical system acetylacetone we report here electron spectra measured as a function of time delay with enough spectral and time resolution to follow several photoexcited species through well-characterized individual steps, interpreted using state-of-the-art static and dynamics calculations. These results open the way for investigations of photochemical processes in unprecedented detail. [ABSTRACT FROM AUTHOR]

New triazolo[1,5-a]pyrimidines containing aroyl and acetyl or ester groups in the pyrimidine ring were synthesized in a process related to the Biginelli-like reaction, using hydrates of arylglyoxals, β-dicarbonyl compounds, and 1H-1,2,4-triazol-5-amine. Reaction was carried out in either sequential or one-pot procedure. [ABSTRACT FROM AUTHOR]

In the present study, two new zinc complexes with the chemical formulas of [Zn(2-Ampy)(Acac)2] (I) and [Zn(p-Van)2(H2O)2] (II) were synthesized and characterized by FT-IR, 1H NMR, and UV-Vis spectroscopy. Moreover, the crystal structures of the complexes were determined by X-ray diffraction technique. Single-crystal X-ray diffraction analyses (CIF files CCDC nos. 1513672 (I) and 1513673 (II)) revealed that complex I has a distorted square pyramid environment, and complex II has a distorted octahedral geometry. The complexes were also screened for in vitro antibacterial activities against some bacteria. The results show that complexes have the effective antibacterial activities. The complexes were employed to prepare ZnO nanoparticles by the combustion synthesis method at 700°C for 8 h. The nanoparticles were characterized, using powder X-ray diffraction analysis (PXRD), scanning electron microscopy and transmission electron microscope. PXRD analysis showed the presence of pure phase in both samples. Furthermore, the crystallite size was approximately 37 and 42 nm for ZnO prepared from complexes I and II, respectively. [ABSTRACT FROM AUTHOR]

The structure of a mixed-ligand complex tris-(dipivaloylmethanato)(ethylendiamine)yttrium(III) [Y(en)(dpm)3] is studied at 150(2) K by single crystal XRD. The crystallographic data for C35H65N2O6Y are as follows: space group P21/c, a = 10.3771(3) Å, b = 26.3566(8) Å, c = 14.8412(4) Å, β = 100.385(2)°, V = 3992.6(2) Å3, Z = 4. The structure is molecular. The coordination environment of yttrium atoms is square antiprismatic; the Y-О distances are 2.2597(13)-2.3760(12) Å and Y-N distances are 2.5381(16) Å and 2.5499(17) Å. [ABSTRACT FROM AUTHOR]

The effect of the features of starting zirconium compounds on the solvothermal synthesis of mixed Ce-Zr oxides in a flow reactor using ethanol and isopropanol as a supercritical medium was studied. The phase composition and structural properties of the synthesized samples were investigated using X-ray diffraction analysis (XRD) and Raman spectroscopy. The morphology and textural properties were studied by transmission electron microscopy (TEM) and thermal desorption of nitrogen. It was found that the use of zirconium oxychloride or acetate as the starting substances results in the formation of a mixture of phases enriched with cerium or zirconium, whereas the use of zirconium butoxide with acetylacetone as a complexing agent allows obtaining a homogeneous solid solution. The catalytic properties of the synthesized oxides with supported Ni were tested in methane dry reforming (MDR). The catalyst containing a single-phase oxide synthesized in the presence of acetylacetone exhibited much higher activity, selectivity and coking stability. [ABSTRACT FROM AUTHOR]

SrAlO nanocomposite was prepared by sol gel method using aluminum isopropoxide, strontium nitrate, acetylacetone and polyethylene glycol as template, followed by calcination at 900 °C. This nanocomposite was characterized by various techniques including X-ray powder diffraction, infrared spectroscopy, elemental analysis, scanning transmission microscope and transmission electron microscope. It was found that SrAlO nanocomposite successfully catalyzes the Knöevenagel condensation of aromatic aldehydes with malononitrile in room temperature in ethanol. Expedient access to the corresponding Knöevenagel adducts in moderate to high yields within 6 min is promising. The recovered catalyst was reused for three times without significant loss of activity. [ABSTRACT FROM AUTHOR]

A one-pot reaction was developed for the synthesis of polyfunctionalized 1,1'-(α,ω-alkanediyl)bis(1,2,3,4-tetrahydropyridines) in 28-69% yields on the basis of a three-component reaction between 1,3-dicarbonyl compounds, aqueous 33% solution of formaldehyde, and α,ω-diamines. [ABSTRACT FROM AUTHOR]

The influence of the aggregate state on the IR luminescence is studied for the Nd(III), Sm(III), and Yb(III) complexes with the thienyl, phenyl, and alkyl derivatives of acetylacetone in solutions and as sorbates on the polymer matrix. It is found that the luminescence intensity of the sorbates of the complexes is 2-3 orders of magnitude higher than that in solutions due to the elimination of diffusion and respective intermolecular nonradiative losses of the excitation energy. [ABSTRACT FROM AUTHOR]