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ABSTRACT Acetylacetone, double‐deuterated acetylacetone and hexafluoroacetylacetone were isolated in inert matrices and investigated by means of Raman scattering and infrared absorption spectroscopic methods, combined with theoretical calculations. The ability of Raman spectroscopy to access low wavenumber modes enables the study of vibrational modes involved in internal hydrogen bonds that are challenging to observe with infrared absorption spectroscopy. An almost complete set of vibrational modes for the studied molecules was observed experimentally, facilitating a comprehensive assessment of different computational approaches. The large dataset obtained allowed for an improved assignment of vibrational bands and firmly confirmed the existence of only one chelated isomer of acetylacetone, double‐deuterated acetylacetone and hexafluoroacetylacetone in matrices. The experimental data also highlighted the effects of deuteration and fluorination. [ABSTRACT FROM AUTHOR]

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]

Novel chiral tetraaza‐bridged calix[4]arene[2]triazine‐based organocatalysts were synthesized and used for catalytic asymmetric Michael reaction of acetylacetone to various aromatic nitrostyrenes. Chiral subunits (R)‐ and (S)‐1,2,3,4‐tetrahydro‐1‐naphthylamine were attached to the tetraaza‐bridged calix[4]arene[2]triazine platform in both enantiomeric forms. The R configuration of the major enantiomer of the Michael product was obtained when 3a was used as catalyst, and the S configuration was obtained when 3b was used as catalyst. This indicated that the configuration of the Michael product was controlled by the chiral calixarene moiety. The Michael adducts were obtained in excellent yields (91%) and enantioselectivities (98%). [ABSTRACT FROM AUTHOR]

The molecule of the title compound, [Ni(C5H7O2)2(C8H9N3)(H2O)]·C2H5OH, has triclinic (P\overline{1}) symmetry. This compound is of interest for its antimicrobial properties. The asymmetric unit comprises two independent complex molecules, which are linked by N—H...O and O—H...O hydrogen bonds along [111]. Hirshfeld surface analysis indicates that 71.7% of intermolecular interactions come from H...H contacts, 17.7% from C...H/H...C contacts and 7.6% from O...H/H...O contacts, with the remaining contribution coming from N...H/H...N, C...N/N...C, C...C and O...O contacts.

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]

• A good accumulation and accommodation of interface is towards acetylacetone (AcAc). • AcAc isomerization is favorable on acidic interface as "water-bridge" is destroyed. • Carbonyl/hydroxyl O-atom of AcAc displays an energetical preference to hydration. • Unfeasible hydration on acidic interface leads to the accumulation of product. Acetylacetone (AcAc) is a typical class of β-diketones with broad industrial applications due to the property of the keto-enol isomers, but its isomerization and chemical reactions at the air-droplet interface are still unclear. Hence, using combined molecular dynamics and quantum chemistry methods, the heterogeneous chemistry of AcAc at the air-droplet interface was investigated, including the attraction of AcAc isomers by the droplets, the distribution of isomers at the air-droplet interface, and the hydration reactions of isomers at the air-droplet interface. The results reveal that the preferential orientation of two AcAc isomers (keto - and enol -AcAc) to accumulate and accommodate at the acidic air-droplet interface. The isomerization of two AcAc isomers at the acidic air-droplet interface is more favorable than that at the neutral air-droplet interface because the "water bridge" structure is destroyed by H 3 O+, especially for the isomerization from keto -AcAc to enol -AcAc. At the acidic air-droplet interface, the carbonyl or hydroxyl O-atoms of two AcAc isomers display an energetical preference to hydration. Keto -diol is the dominant products to accumulate at the air-droplet interface, and excessive keto -diol can enter the droplet interior to engage in the oligomerization. The photooxidation reaction of AcAc will increase the acidity of the air-droplet interface, which indirectly facilitate the uptake and formation of more keto -diol. Our results provide an insight into the heterogeneous chemistry of β-diketones and their influence on the environment. [Display omitted] [ABSTRACT FROM AUTHOR]

The sulfonamide‐derived compounds have demonstrated various pharmaceutical properties. However, the exploration of certain properties, such as phosphatase inhibition and anti‐thyroid activities, has been limited in the existing literature. The present study aimed to investigate these specific activities for the Schiff base (Z)‐4‐(4‐oxopent‐2‐en‐2‐ylamino)benzenesulfonamide. The compound underwent thorough physicochemical characterization, including FTIR, Raman, and UV‐Vis spectroscopy, along with theoretical DFT calculations. It exhibited inhibitory activity against intestinal alkaline phosphatase, showing an IC50 value of 37.0±1.0 μM, with kinetic studies indicating a mixed mode of inhibition. Additional insights into the inhibition process were gained through fluorescence spectroscopy and molecular docking studies. The potential anti‐thyroid activity was explored through charge‐transfer studies with iodine, revealing a strong interaction (Kc=2.16±0.05×104 M−1), suggesting a role in reducing the iodination process of triiodothyronine (T3) and thyroxine (T4). Moreover, the compound showed strong, spontaneous, and reversible binding to albumin, indicating potential pharmaceutical relevance. ADME properties were also calculated, confirming favorable drug‐likeness. This study provides valuable insights into the multifaceted pharmaceutical properties of the investigated sulfonamide‐derived compound, encouraging further exploration of its therapeutic potential. [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]

Typical metal–organic frameworks (MOFs) usually suffer from a limited visible light-trapping ability and easy recombination of charge carriers, hindering their photocatalytic applications. Acetylacetone (AA), leveraging its exceptional coordination capabilities, serves as a versatile and effective modifier for enhancing the photocatalytic activity of MOFs via a post-synthesis approach. The synthesis of diketone-anchored MOFs with AA can be achieved by first diazotizing the amino groups on the ligands of MOFs, followed by a condensation reaction between AA and the resulting azide. Gradient AA loadings ranging from 17% to 98% were obtained, showcasing the tunability of this approach. Interestingly, a sub-stoichiometric effect was exhibited between the AA loading and the visible photocatalytic performance of the modified photocatalyst. The singlet oxygen yields of MIL-125-AA-37% and MIL-125-AA-54% were about 1.3 times that of MIL-125-AA-17% and 3.0 times that of MIL-125-AA-98%. The improved photocatalytic activity could be attributed to the fact that the AA modification altered the electron density of the Ti metal center, leading to the creation of a significant amount of oxygen defects. This alteration resulted in a reduction in the recombination of charge carriers and thus a better charge separation. In short, AA modification provides a new strategy to maximize the visible photocatalytic performance of MOFs. [ABSTRACT FROM AUTHOR]

The broadband UV photochemistry kinetics of acetylacetaldehyde, the hybrid form between malonaldehyde and acetylacetone (the two other most simple molecules exhibiting an intramolecular proton transfer), trapped in four cryogenic matrices, neon, nitrogen, argon, and xenon, has been followed by FTIR and UV spectroscopy. After deposition, only the two chelated forms are observed while they isomerize upon UV irradiation toward nonchelated species. From previous UV irradiation effects, we have already identified several nonchelated isomers, capable, in turn, of isomerizing and fragmenting; even fragmentation seems to be most unlikely due to cryogenic cages confinement. Based on these findings, we have attempted an approach to understand the reaction path of electronic relaxation. Indeed, we have demonstrated, in previous studies, that in the case of malonaldehyde, this electronic relaxation pathway proceeds through singlet states while it proceeds through triplet ones in the case of acetylacetone. We observed CO and CO2 formations when photochemistry is almost observed among nonchelated forms, i.e., when the parent molecule is almost totally consumed. In order to identify a triplet state transition, we have tried to observe a "heavy atom effect" by increasing the weight of the matrix gas, from Ne to Xe, and to quench the T1 state by doping the matrices with O2. It appears that, as in the case of acetylacetone, it is the nonchelated forms that fragment. It also appears that these fragmentations certainly take place in the T1 triplet state and originate in an Π* ← n transition. [ABSTRACT FROM AUTHOR]

Four bifunctional, noncovalent amine-squaramide organocatalysts were prepared from camphor in five steps. The stereochemistry of the prepared catalysts was thoroughly analyzed using various spectroscopic techniques. Their organocatalytic activity was investigated in the Michael addition of acetylacetone to trans-β-nitrostyrene. The addition product was formed in complete conversion and with an enantioselectivity of up to 77% ee. In the reactions catalyzed by the 2-exo-3-endo catalysts, the major (S)-enantiomer was formed, whereas in the presence of 2-endo-3-endo catalysts, the (R)-enantiomer was formed as the major product. [ABSTRACT FROM AUTHOR]

A new ibuprofen derivative, (E)-2-(4-isobutylphenyl)-N′-(4-oxopentan-2-ylidene) propane hydrazide (IA), was synthesized, along with its metal complexes with Co, Cu, Ni, Gd, and Sm, to investigate their anti-inflammatory efficacy and COX-2 inhibition potential. Comprehensive characterization, including 1H NMR, MS, FTIR, UV–vis spectroscopy, and DFT analysis, were employed to determine the structural configurations, revealing unique motifs for Gd/Sm (capped square antiprismatic/tricapped trigonal prismatic) and Cu/Ni/Co (octahedral) complexes. Molecular docking with the COX-2 enzyme (PDB code: 5IKT) and pharmacokinetic assessments through SwissADME indicated that these compounds have superior binding energies and pharmacokinetic profiles, including BBB permeability and gastrointestinal absorption, compared to the traditional ibuprofen standalone. Their significantly lower IC50 values further suggest a higher efficacy as anti-inflammatory agents and COX-2 inhibitors. These research findings not only introduce promising ibuprofen derivatives for therapeutic applications but also set the stage for future validation and exploration of this new generation of ibuprofen compounds. [ABSTRACT FROM AUTHOR]

In designing efficient perovskite solar cells (PSCs), the selection of suitable electron transport layers (ETLs) is critical to the final device performance as they determine the driving force for selective charge extraction. SnO2 nanoparticles (NPs) based ETLs have been a popular choice for PSCs due to superior electron mobility, but their relatively deep‐lying conduction band energy levels (ECB) result in substantial potential loss. Meanwhile, TiO2 NPs establish favorable band alignment owing to shallower ECB, but their low intrinsic mobility and abundant surface trap sites impede the final performance. For this reason, constructing a cascaded bilayer ETL is highly desirable for efficient PSCs, as it can rearrange energy levels and exploit on advantages of an individual ETL. In this study, we prepare SnO2 NPs and acetylacetone‐modified TiO2 (Acac‐TiO2) NPs and implement them as bilayer SnO2/Acac‐TiO2 (BST) ETL, to assemble cascaded energy band structure. SnO2 contributes to rapid charge carrier transport from high electron mobility while Acac‐TiO2 minimizes band‐offset and effectively suppresses interfacial recombination. Accordingly, the optimized BST ETL generates synergistic influence and delivers power conversion efficiency (PCE) as high as 23.14% with open‐circuit voltage (VOC) reaching 1.14 V. Furthermore, the BST ETL is transferred to a large scale and the corresponding mini module demonstrates peak performance of 18.39% PCE from 25 cm2 aperture area. Finally, the BST‐based mini module exhibit excellent stability, maintaining 83.1% of its initial efficiency after 1000 h under simultaneous 1 Sun light‐soaking and damp heat (85 °C/RH 85%) environment. [ABSTRACT FROM AUTHOR]

The new 3-monosubstituted acetylacetone ligands, 3-(phenyl(1H-pyrazol-1-yl)methyl)pentane-2,4-dione (HLacPz) and 3-((3,5-dimethyl-1H-pyrazol-1-yl)(phenyl)methyl)pentane-2,4-dione (HLacPzMe), were synthesized and used as supporting ligands for new copper(II) and copper(I) phosphane complexes of the general formulae [Cu(HLacX)2(LacX)2] and [Cu(PPh3)2(HLacX)]PF6 (X = Pz (pyrazole) or PzMe (3,5-dimethylpyrazole)), respectively. In the syntheses of the Cu(I) complexes, the triphenylphosphine coligand (PPh3) was used to stabilize copper in the +1 oxidation state, avoiding oxidation to Cu(II). All compounds were characterized by CHN analysis, 1H-NMR, 13C-NMR, FT-IR spectroscopy, and electrospray ionization mass spectrometry (ESI-MS). The ligands HLacPz (1) and HLacPzMe (2) and the copper complex [Cu(PPh3)2(HLacPz)]PF6 (3) were also characterized by X-ray crystallography. The reactivity of these new compounds was investigated and the new compounds 4-phenyl-4-(1H-pyrazol-1-yl)butan-2-one (7) and 4-(3,5-dimethyl-1H-pyrazol-1-yl)-4-phenylbutan-2-one (8) were obtained in basic conditions via the retro-Claisen reaction of related 3-monosubstituted acetylacetone, providing efficient access to synthetically useful ketone compounds. Compound 8 was also characterized by X-ray crystallography. [ABSTRACT FROM AUTHOR]

• Acetylacetone outperformed H 2 O 2 in degrading algal metabolites under xenon irradiation. • Protein-like constituents were more susceptible to photodegradation by acetylacetone. • The biological toxicity of microcystin-LR was greatly reduced after photooxidation. • The photoactivity of acetylacetone was limited by alkaline pH, not by inorganic ions. Inactivation of cyanobacterial cells and simultaneous control of secondary metabolites is of significant necessity for the treatment of cyanobacteria-laden water. Acetylacetone (AcAc) has been reported a specific algicide to inactivate Microcystis aeruginosa (M. aeruginosa) and an effective light activator to degrade pollutants. This study systematically investigated the photodegradation ability of AcAc under xenon (Xe) irradiation on the secondary metabolites of M. aeruginosa , mainly algal organic matter (AOM), especially toxic microcystin-LR (MC-LR). Results showed that AcAc outperformed H 2 O 2 in destructing the protein-like substances, humic acid-like matters, aromatic proteins and fulvic-like substances of AOM. For MC-LR (250 µg/L), 0.05 mmol/L AcAc attained the same degradation efficiency (87.0%) as 0.1 mmol/L H 2 O 2. The degradation mechanism of Xe/AcAc might involve photo-induced energy/electron transfer and formation of carbon center radicals. Alkaline conditions (pH > 9.0) were detrimental to the photoactivity of AcAc, corresponding to the observed degradation rate constant (k 1 value) of MC-LR drastically decreasing to 0.0013 min−1 as solution pH exceeded 9.0. The PO 4 3− and HCO 3 − ions had obvious inhibition effects, whereas NO 3 − slightly improved k 1 value from 0.0277 min−1 to 0.0321 min−1. The presence of AOM did not significantly inhibit MC-LR degradation in Xe/AcAc system. In addition, the biological toxicity of MC-LR was greatly reduced after photoreaction. These results demonstrated that AcAc was an alternative algicidal agent to effectively inactivate algal cells and simultaneously control the secondary metabolites after cell lysis. Nevertheless, the concentration and irradiation conditions should be further optimized in practical application. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, arylglyoxals, acetylacetone, and 2,6-dimethyl phenol or 2,6-di-tert-butyl phenol are combined to efficiently synthesize a series of 1-(4-(3,5-dialkylphenyl)-2-methyl-5-phenylfuran-3-yl) ethan-1-one derivatives in excellent yields. These reactions were carried out in acetone at reflux under catalyst-free conditions in the presence of triethylamine as a base for 3 h. NMR, FT-IR, EI-MS, and elemental studies were used to characterize the products' structural characteristics. The present study has also several benefits, such as excellent yields and the ease of workup procedure, making it an appealing, practical, and acceptable one-pot method for producing functionalized derivatives of dialkyl furan. [ABSTRACT FROM AUTHOR]

Solar energy has been the most emphasized issue in recent years, as it is sustainable and causes zero emissions. In the solar cell industry, new manufacturing protocols have led to the development of materials with enhanced properties. Over the past decades, perovskite solar cells (PSC) have obtained a power conversion efficiency (PCE) to be 25% due to the development of synthesis techniques, electrode materials, etc. There is an important relationship between the thickness of the transport layers (hole and electron) in the case of improving the yield of perovskite solar cells. We have investigated the influence of the acid-assisted and acetylacetone-assisted (AA) methods on TiO2 films and thus the effect on the PCE of perovskite solar cells. Perovskite (CH3NH3PbI3) layer and different compact TiO2 (c-TiO2) layers have been coated by the spin coating method, and the overall experimental section is made in the nitrogen medium at room temperature. Through an acid-assisted method, the cracked c-TiO2 film was formed. The planar solar cell structure of ITO/AA-TiO2/CH3NH3PbI3/P3HT/Ag resulted in 0.03% of PCE. However, the perovskite solar cells with a mesoporous solar cell structure of ITO/ AA-TiO2/m-TiO2 /CH3NH3PbI3/P3HT/Ag resulted in 0.1% of PCE. [ABSTRACT FROM AUTHOR]

A series of polymer membranes containing various polymers such as: poly(vinyl chloride) (PVC), cellulose triacetate (CTA), polyethylene (PE), and poly(lactide) (PLA), and plasticizers (bis(2-ethylhexyl) adipate) (ADO) or 2-nitrophenyl octyl ether (2-NPOE), and acetylacetone (Acac) as a carrier were applied for the removal of cadmium(II) ions from aqueous solutions. The surface wettability of the obtained membranes and their chemical composition (determined by wavelength-dispersive X-ray fluorescence spectroscopy) were characterized. The obtained results indicate that the adsorption of Cd(II) ions on all examined polymer membranes (PM-1: PVC/ADO/Acac, PM-2: PE/ADO/Acac, PM-3: CTA/2-NPOE/Acac, PM-4: PLA/2-NPOE/Acac) occurred very quickly, and after 10 min of the processes, the percentage of bound cadmium(II) ions reached about 70%. The best result for the removal of cadmium(II) ions (86%) was obtained after 3h of the process conducted using the PM-3. The application of the PM-4 membrane, containing PLA enabled removal of 85% of Cd(II) ions after 0.5 h of the process. The possibility of using a biodegradable PLA as a membrane matrix is part of the so-called "Green Chemistry", and the results obtained using membranes containing synthetic polymers and natural PLA are similar. The estimated production costs of PLA-based membrane are higher than membranes containing synthetic PVC, CTA or PE. [ABSTRACT FROM AUTHOR]

A new Zn(II) metal–organic framework (MOF) with the formula [Zn(BBIP)(2,6-NDC)]n (JXUST-44, BBIP = 3,5-bis(1H-benzo[d]imidazol-1-yl)pyridine and 2,6-H2NDC = 2,6-naphthalic acid) was synthesized under solvothermal conditions. The adjacent Zn(II) ions are connected by BBIP ligands to form one-dimensional (1D) chains, which are further linked by carboxylate groups of 2,6-NDC2− ligands to obtain a two-dimensional layer structure, resulting in a 2D → 3D polycatenated MOF. JXUST-44 can be simplified as a 4-connected sql topology and shows good chemical stability in a wide pH range from 2 to 12 at room temperature. The fluorescence experiments indicate that JXUST-44 presents sensitive and selective detection of salicylaldehyde (SA), acetylacetone (acac) and H2PO4− with the detection limits of 0.074, 10.311 and 0.011 ppm, respectively. It is worth noting that JXUST-44 shows turn-on fluorescence toward acac and H2PO4−, as well as good recyclability and stability for acac, SA and H2PO4−. Therefore, JXUST-44 can be considered as a good fluorescent sensor for acac, SA and H2PO4−. The sensing mechanism has also been studied in detail. [ABSTRACT FROM AUTHOR]

A new Zn(II) metal–organic framework (MOF) with the formula [Zn(BBIP)(2,6-NDC)]n (JXUST-44, BBIP = 3,5-bis(1H-benzo[d]imidazol-1-yl)pyridine and 2,6-H2NDC = 2,6-naphthalic acid) was synthesized under solvothermal conditions. The adjacent Zn(II) ions are connected by BBIP ligands to form one-dimensional (1D) chains, which are further linked by carboxylate groups of 2,6-NDC2− ligands to obtain a two-dimensional layer structure, resulting in a 2D → 3D polycatenated MOF. JXUST-44 can be simplified as a 4-connected sql topology and shows good chemical stability in a wide pH range from 2 to 12 at room temperature. The fluorescence experiments indicate that JXUST-44 presents sensitive and selective detection of salicylaldehyde (SA), acetylacetone (acac) and H2PO4− with the detection limits of 0.074, 10.311 and 0.011 ppm, respectively. It is worth noting that JXUST-44 shows turn-on fluorescence toward acac and H2PO4−, as well as good recyclability and stability for acac, SA and H2PO4−. Therefore, JXUST-44 can be considered as a good fluorescent sensor for acac, SA and H2PO4−. The sensing mechanism has also been studied in detail. [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]

The bench-scale experimental study intends to explore the degradation mechanism of methyl orange (MO) using an advanced oxidation system which combines UV with acetylacetone (AA). As a result, the experimental study presented that the UV/AA system was much better than the UV/H2O2 system with respect to the effectiveness of decolorizing MO, as the initial concentration of MO in the wastewater was 15 mg/L and the dosage of AA was 0.5 mmol/L, the degradation rate of MO could be as high as 98.4% after photolysis of 12 min, and in the UV/AA system the degradation of MO was in compliance with the zero-order-kinetic model (R²>0.990) regardless the initial mass concentration. When the value of pH was approximately 2.0, the degradation rate of MO in 6 min. could reach up to 99.3%, an increase of 58.1% higher than that the pH of 9.0 or so. On the other hand, the inorganic anion HCO3- had a significantly inhibitory effect on the system, low concentration of Cl- slightly promoted it, while high concentrations, and SO42- made almost no effects on the degradation rate, and the printing/dyeing auxiliary sodium citrate also exerted notable adverse effect on the degradation of MO. Furthermore, the results of free-radical-capture experiment and the electron paramagnetic resonance (EPR) test indicated that the most of the active-oxides in the UV/AA system was ¹O2. The result of treating printing/dyeing wastewater in terms of TOC indicated that this UV/AA advanced system had a certain degree of mineralization ability; UV-Vis absorption spectroscopy analysis showed that the azo bond was basically broken down in 12 min; and AA concentration decreased as the reaction being in progression. According to the results of analysis using LC-MS, it was speculated the conversion pathway of MO in the degradation process of UV/AA advanced oxidation system. [ABSTRACT FROM AUTHOR]

Typical metal–organic frameworks (MOFs) usually suffer from a limited visible light-trapping ability and easy recombination of charge carriers, hindering their photocatalytic applications. Acetylacetone (AA), leveraging its exceptional coordination capabilities, serves as a versatile and effective modifier for enhancing the photocatalytic activity of MOFs via a post-synthesis approach. The synthesis of diketone-anchored MOFs with AA can be achieved by first diazotizing the amino groups on the ligands of MOFs, followed by a condensation reaction between AA and the resulting azide. Gradient AA loadings ranging from 17% to 98% were obtained, showcasing the tunability of this approach. Interestingly, a sub-stoichiometric effect was exhibited between the AA loading and the visible photocatalytic performance of the modified photocatalyst. The singlet oxygen yields of MIL-125-AA-37% and MIL-125-AA-54% were about 1.3 times that of MIL-125-AA-17% and 3.0 times that of MIL-125-AA-98%. The improved photocatalytic activity could be attributed to the fact that the AA modification altered the electron density of the Ti metal center, leading to the creation of a significant amount of oxygen defects. This alteration resulted in a reduction in the recombination of charge carriers and thus a better charge separation. In short, AA modification provides a new strategy to maximize the visible photocatalytic performance of MOFs.

Aqueous Zn ion batteries are appealing systems owing to their safety, low cost, and environmental friendliness; however, their practical applicability is impeded by the growth of Zn dendrites and side reactions. Herein, a dual‐functional electrolyte additive, namely acetylacetone (AT) is utilized for the simultaneous regulation of the solventized structure and anode–electrolyte interface (AEI) to achieve a durable, dendrite‐free Zn anode. Theoretical calculations and experimental characterizations reveal that the AT molecule can be adsorbed onto Zn metal surface to reconstruct the AEI and allow for the primordial desolvation of [Zn(H2O)6]2+ at locations away from the surface of the Zn anode during deposition, which is attributed to the strong polarity of the carbonyl functional group. In addition, the two carbonyls of AT can replace two H2O molecules in the primary solventized structure of Zn2+ to reduce the number of active H2O molecules, efficiently suppressing Zn dendrite growth and detrimental reactions. As a proof of concept, a Zn//Cu cell is constructed in ZnSO4 containing 3 vol.% AT electrolyte, delivering stable cycling over 1800 cycles while maintaining a high Coulombic efficiency of 99.74%. This study provides a practical approach for inhibiting dendrite growth and side reactions by harnessing carbonyl chemistry. [ABSTRACT FROM AUTHOR]

Quinobenzazepines are useful in medicinal chemistry, but their synthesis is very challenging. Herein, we designed and synthesized a range of multi‐functional chalcone‐based quinolinium salts; their synthetic application in the rapid and straightforward construction of quinobenzazepines was successfully explored. A wide range of oxa‐bridged quinobenzazepine polycycles were afforded serendipitously through a dearomative cascade reaction of our newly developed quinolinium salts and acetylacetone. This synthetic strategy features high bond‐ and ring‐forming efficiency and complete regio‐ and diastereoselective control. [ABSTRACT FROM AUTHOR]

A physical chemistry experiment involving organic chemistry, computational chemistry, and instrumental analysis is described for junior students majoring in chemistry. Keto-enol tautomerism is a fundamental concept in undergraduate organic chemistry. The keto-enol tautomeric equilibrium of acetylacetone in a series of binary solvent mixtures of deuterated chloroform and deuterated dimethyl sulfoxide with various polarities was explored using NMR spectroscopy and theoretical computations. The effect of solvent polarity on the equilibrium is discussed in combination with NMR and theoretical computation results. This experiment facilitates students' understanding of abstract concepts enables them to integrate theory with experiments and systematically analyze multiple techniques to explore chemical processes and principles. [ABSTRACT FROM AUTHOR]

In this work, some new pyrazole derivatives were prepared through the reaction of the diazonium salt of metoclopramide with acetylacetone to give 5-chloro-N-(2- (diethylamino)ethyl)-4-((2,4-dioxopentan-3-yl) diazenyl)-2-methoxybenzamide (1) in 80% yield. Compound 1 was then reacted with some hydrazine derivatives to afford the corresponding pyrazole derivatives in 75-93% yields. Some new azo compounds (6-10) were also prepared in 77-95% yields by treatment of the diazonium salt of metoclopramide with some phenol and aniline derivatives. The prepared compounds were characterized using FT-IR and 1H NMR spectroscopy. Some of these compounds were then tested to see how well they worked as antioxidants. [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]

【Objective】The study was conducted to establish a fast method for the detection of formaldehyde content in vegetables, identify the residue level and understand the dietary exposure risk of formaldehyde in vegetables.【Method】The single factor experiment was used to optimize the key experimental conditions, and then a method acetylacetone spectrophotometry for the detection of formaldehyde contents in vegetables was established. The formaldehyde contents of 383 vegetable samples were analyzed and the exposure risk of formaldehyde in vegetables was assessed with point evaluation method.【Result】The detection limit and the quantitation limit for the determination of formaldehyde in vegetables with acetylacetone spectrophotometry were 0.45 and 1.5 mg/kg, respectively; At the added levels of 1.5, 7.5 and 15 mg/kg, the recovery rates ranged from 86.33% to 92.4% with the relative standard deviations were of 2.23%-4.21%. The detection rates of formaldehyde in different vegetables were 5.00%-72.73% with the total detection rate of 26.37%, and the average detection values of different vegetables were 0.47-1.67 mg/kg. The dietary exposure levels of formaldehyde contents in different vegetables to the general population ranged from 0.0019 to 0.068 mg/kg (bw/d) with the MOS ranging from 14.1 to 289.8, and the dietary exposure levels of formaldehyde contents in vegetables to different populations were 0.0060-0.15 mg/kg (bw/d) with the MOS ranging from 10.1 to 33.3. All the evaluated values of MOS were greater than 1.【Conclusion】The method of acetylacetone spectrophotometry is simple, accurate and sensitive, which is suitable for the fast determination of formaldehyde in vegetables. The dietary intake risk of formaldehyde residues in vegetables is low and within the acceptable range.

Asymmetrically substituted porphyrins possessing ethyl acetoacetate or acetylacetone (EAA or acac) with six bromine atoms at β-positions were synthesized and then characterized by various spectroscopic techniques, such as UV-Vis, fluorescence and NMR, and also by CV, DFT, MALDI-TOF-MS and elemental analysis. The mechanistic pathway followed the nucleophilic substitution reaction (nucleophile: EAA and acac) with MTPP(NO2)Br6 (M = 2H, Cu(II), and Ni(II)), and the resultant β-heptasubstituted porphyrins exhibited keto–enol tautomerism, as supported by 1H NMR spectroscopy. The six bulky bromo and EAA/acac groups made the macrocyclic ring highly electron deficient and nonplanar such that the quantum yield and fluorescence intensity for H2TPP[EAA]Br6 and H2TPP[acac]Br6 were severely reduced in contrast to those values for H2TPP. The poor electron density and nonplanarity over the porphyrin ring shifted the first oxidation potential from 11 to 521 mV anodically for MTPP[X]Br6 [M = 2H, Cu(II), and Ni(II); X = EAA or acac] as compared to corresponding MTPPs. Notably, density functional theory proved the nonplanarity of the synthesized porphyrins as Δ24 spans from ±0.546 to ± 0.559 Å while ΔCβ stretches from ±0.973 to ±1.162 Å. The third-order nonlinear optical measurements were performed using the femtosecond pulsed laser Z-scan technique at 800 nm and 1 kHz repetition rate to acquire insights into nonlinear absorption and nonlinear refraction of the porphyrins. The three-photon absorption coefficients (γ) are in the range of 2.2 × 10−23–2.8 × 10−23 cm3 W−2 and the nonlinear refractive index values were in the range of 3.7 × 10−16–5.1 × 10−16 cm2 W−1. The higher-order nonlinear absorption exhibited by porphyrins helps improve resolution at depth for various photonic and optoelectronic applications. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) has been used to investigate the mechanism of the experimentally efficient hydroalkylation of styrene with acetylacetone in the presence of a bismuth catalyst. It is shown that the mechanism is fundamentally different to that of the analogous gold-catalysed reaction, even though it leads to the same product. Whereas gold prefers to coordinate to the π-bond of the enol isomer of acetylacetone, bismuth coordinates to the two oxygens to form a chelated complex. Furthermore, the overall reaction with bismuth via the enol isomer of acetylacetone occurs with a much lower activation energy compared to the ketone isomer. In addition, several bismuth catalysts were considered and two of these were shown to have no activity. All of these results have been rationalised in terms of the strength of binding of the metal centres to the acetylacetone. The stronger the binding, the greater the acidity of a proton on acetylacetone, and thus the lower the activation energy for the protonation of styrene, which turns out to be the rate-determining step in the overall reaction. In this way, good agreement is obtained with all the experimental data. [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]

(2R,4R)‐Pentanediol is an interesting precursor for the synthesis of chiral ligands. A ketoreductase (KRED) was employed for the asymmetric reduction of acetylacetone to this diol. Biocatalysis often suffers from low concentrations of hydrophobic substrates and low stability of the enzyme in unconventional media. Here, we present an engineered KRED variant applicable in a neat substrate system, including upscaling to the multi‐liter scale and downstream processing (DSP). Our engineered KRED applied in a neat substrate system is a powerful technique for the synthesis of chiral diols yielding product concentrations of 208 g L−1. [ABSTRACT FROM AUTHOR]

The investigation of the reactivity of an α-amido sulfone derived from 2-formyl benzoate under organocatalytic conditions in the presence of acetylacetone allowed the synthesis of a new heterocyclic hybrid isoindolinone-pyrazole with high enantiomeric excess. Dibenzylamine was also used as a nucleophile to afford an isoindolinone with aminal substituent in 3-position in suitable selectivity. The use of Takemoto's bifunctional organocatalyst not only led to observed enantioselectivity but was also important in accomplishing the cyclization step in both cases. Notably, this catalytic system proved to be particularly effective in comparison to widely used phase transfer catalysts. [ABSTRACT FROM AUTHOR]

Temperature‐dependent rate constants for the reactions of CH2OO with acetone (Ac), biacetyl (BiAc), and acetylacetone (AcAc) have been measured over the range 275–335 K using a flash photolysis, transient absorption spectroscopy technique. The measurements were performed at a total pressure of ∼80 Torr in N2 bath gas, which corresponds to the high‐pressure limit for these reactions. All three reactions show linear Arrhenius plots with negative temperature dependences. Rate constants increase in the order Ac < AcAc « BiAc across the temperature range; at 295 K the rate constants are kAc = (4.8 ± 0.4) × 10–13 cm3 s–1, kAcAc = (8.0 ± 0.7) × 10–13 cm3 s–1, and kBiAc = (1.10 ± 0.09) × 10–11 cm3 s–1. Sensitivity to temperature, characterized by the magnitude of the negative activation energy, increases in the order AcAc < BiAc < Ac (Ea/R values of –1830 ± 170 K, –1260 ± 170 K, and –460 ± 180 K, respectively). CBS‐QB3 calculations show that the Ac and BiAc reactions proceed via formation of an entrance channel complex followed by 1,3‐dipolar cycloaddition to form secondary ozonide products via a submerged transition state. For the BiAc reaction, the rate limiting step appears to be rearrangement of a long‐range van der Waals complex into the short‐range complex that subsequently leads directly to the cycloaddition transition state with a very low energy barrier. The calculations show that two reaction pathways are competitive for AcAc with nearly identical transition state free energies (ΔG° = +10.1 kcal mol–1 at 298 K) found for cycloaddition at the C=O and at the C=C site of the dominant enolone tautomer. The weak temperature dependence observed is likely due to competition between these pathways. [ABSTRACT FROM AUTHOR]

The research work presents the synthesis, spectral characterization (UV, FT-IR, and NMR), and modelling of tricarbonyl rhenium complexes (R1, R2, R3, R4, and R5) bearing the β-diketone ligand and acetylacetone (Acac) for potential application as cancer drugs. The theoretical investigation was carried out within the framework of density functional theory (DFT) computation at the ωB97XD/Gen/6–311++G (d,p)/LanL2DZ level of theory. The studied rhenium complexes: fac-[Re(Acac)(CO)3(H2O)] (R1),fac-[Re(Acac)(CO)3(Py)] (R2), fac-[Re(Acac)(CO)3(Im)] (R3), fac-[Re(Acac)(CO)3(1-CH3Im)] (R4),fac-[Re(Acac)(CO)3(Pz)] (R5) follows an increasing pattern of stability: R5 < R4 < R2 < R3 < R1, with energy gap values of 6.4487, 6.6281, 7.6758, 7.7487 and 8.0608 eV respectively. The MolDock score ranges from -65.769 to -42.141 kcal/mol compared to the much smaller value of -13.191 kcal/mol for Cisplatin (Cispt) interaction with 2ES3, indicating that the rhenium complex ligands exhibit higher inhibitory activities against TNC to promote apoptosis and regulate cell cycle associated with breast cancer compared to Cispt. The highest score is R4 at -115.954 with HBond energy of -2.923 kcal/mol, then followed by R2 with a score of -103.773 and H-Bond energy bond of -0.392 kcal/mol due to only Steric interaction and R3 with a score of -102.885 and H-bond of -0.2259 kcal/mol due to steric interaction with Phe16(I), Val17(I), Cys53(B) amino acid similar to R2. Due to their stability and MolDock score, R2 and R3 complexes exhibit the potency to be used as potential anti-breast cancer drug participants.

In this work, the interaction of diarylmethylidene piperidones with acetylacetone and acetoacetic ester has been studied. It has been shown that the transition to piperidone in the basis of dienone does not allow the selective synthesis of products. It has been found that the direction of the reaction with 1,3-C,C-dinucleophilic reagents is infl uenced by the nature of peripheral ylidene substituents, which allows targeted synthesis of O-heterocyclization products (hexahydropyranopyridines) by introducing an NO2 group into the arylmethylidene fragment. Previously unknown substituted deca(octa)hydro(xanthenes)cyclopentachromenes have been synthesized. It has been established that the interaction of diarylmethylidenecyclanones with cyclohexa(penta)ne under conditions of mild basic catalysis (piperidine) proceeds nonselectively, the size of the cycle in the base of the initial substrate plays an important role, and the reaction products are always a mixture of substances (two or more). Based on the experimental data obtained, a scheme has been proposed for the formation of hydroxanthene and hydrocyclopentachromene fragments of the resulting products. It has been found that, while maintaining the general direction of the reaction, the determining role in the structure of the products is played by the size of the cycle (С5 ,С6 ) in the basis of the initial substrates. Six-membered fused fragments promote enolization and intramolecular O-heterocyclization of 1,5-diketone with the formation of polycyclic systems. The composition and structure of the synthesized compounds have been confi rmed by elemental analysis, IR and one-dimensional, two-dimensional NMR spectroscopy.

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