Comparative material study and synthesis of 4-(4-nitrophenyl)oxazol-2-amine via sonochemical and thermal method

The present paper deals with the synthesis of aminooxazole derivatives via thermal and ultrasonic methods using deep eutectic solvent as medium. It was observed that ultrasound-assisted method gave 90% yield in just 8 min as against 3.5 h required to get 69% yield by thermal method. One of the compounds 4-(4-nitrophenyl)-1,3-oxazol-2-amine synthesized by both methods were subjected to material characterization study via XRD, TGA and SEM analysis. It was observed that use of ultrasound not only increased the rate of reaction but also improved the quality of product obtained. The crystallinity of the product from ultrasound method was 21.12% whereas thermal method fetched only 8.33% crystallinity thereby improving crystallinity by almost 60%. In addition, sonochemical synthesis also saved more than 70% energy as depicted by energy calculations.     

水杨醛缩对乙酰基苯胺希夫碱的合成及其荧光性质的理论研究

以水杨醛和对乙酰基苯胺为原料,首次采用绿色环保的室温固相反应方法制备了水杨醛缩对乙酰基苯胺希夫碱,用元素分析和核磁共振氢谱对产物进行了表征。测定了产物的紫外光谱、荧光光谱和相对荧光量子效率,发现该化合物具有较强的荧光性质。利用密度泛函理论(density functional theory, DFT)方法,在B3LYP/6-311G基组水平上优化了该化合物的基态分子构型。采用相同的方法和基组计算了标题化合物的振动频率,频率数据中没有虚频,即该优化构型是稳定的。分析理论计算结果发现：标题分子具有较强的芳香性和较大共轭体系。在基态优化结构的基础上应用含时密度泛函理论(TD-DFT),在B3LYP/6-31G水平上计算并研究了此化合物的吸收光谱。用单激发组态相互作用(CIS)方法优化了标题分子的激发态构型,并在此基础上用TD-DFT//B3LYP/6-31G方法计算了这种化合物的荧光发射光谱。将理论计算的光谱性质与实验的光谱数据相比较发现二者吻合较好。分析探讨了化合物分子的结构与其荧光性质之间的关系,为进一步寻找具有荧光性质的化合物提供了理论指导。     

Synthesis of NaP zeolite at room temperature and short crystallization time by sonochemical method

NaP zeolite nano crystals were synthesized by sonochemical method at room temperature with crystallization time of 3 h. For comparison, to insure the effect of sonochemical method, the hydrothermal method at conventional synthesis condition, with same initial sol composition was studied. NaP zeolites are directly formed by ultrasonic treatment without the application of autogenous pressure and also hydrothermal treatment. The effect of ultrasonic energy and irradiation time showed that with increasing sonication energy, the crystallinity of the powders decreased but phase purity remain unchanged. The synthesized powders were characterized by XRD, IR, DTA TGA, FESEM, and TEM analysis. FESEM images revealed that 50 nm zeolite crystals were formed at room temperature by using sonochemical method. However, agglomerated particles having cactus/cabbage like structure was obtained by sonochemical method followed by hydrothermal treatment. In sonochemical process, formation of cavitation and the collapsing of bubbles produced huge energy which is sufficient for crystallization of zeolite compared to that supplied by hydrothermal process for conventional synthesis. With increasing irradiation energy and time, the crystallinity of the synthesized zeolite samples increased slightly.     

Synthesis of new 1,5-diaryl-3-(arylamino)-1H-pyrrol-2(5H)-ones under catalyst-free and solvent-free conditions

Several new 1,5-diaryl-3-(arylamino)-1H-pyrrol-2(5H)-ones were synthesized via the three-component condensation reaction of aldehydes, aromatic amines, and ethyl pyruvate under catalyst-free and solvent-free conditions. Also, 5-(4-hydroxyl-3-nitrophenyl)-1-(4-methoxy-phenyl)-3-(4-methoxyphenylamino)-1,5-dihydro-pyrrol-2-one was synthesized using oxime instead of aldehyde. The eco-friendly, simple procedure, green procedure, catalyst-free and solvent-free conditions, short reaction times, and high yields of the products are the advantages of this method.     

Quantum chemical insight into molecular structure,density functional theory calculations,vibrational dynamics,natural population analysis,Hirshfeld analysis,and molecular docking approach to chalcone 1-4-bromophenyl-3-(2-methoxyphenyl)prop-2-en-1-one

The structure of the novel chalcone 1-4-bromophenyl-3-(2-methoxyphenyl)prop-2-en-1-one has been characterized by Fourier transform infrared and Fourier transform Raman. Density functional theory with Becke, 3-parameter, Lee-Yang-Parr functional was used for the optimization of geometry. The comprehensive assignments of the vibrational spectra have been performed with the aid of normal coordinate analysis. Stability of the molecule and intra/intermolecular charge transfer have been analyzed using natural bond orbital analysis. The existence of intermolecular C-H?O, blueshifted hydrogen bond was investigated by bond length variation. Hirshfeld and two-dimensional fingerprint plot analyses have been performed to study the nature of interactions present in the molecule. The docked complex gives a constancy of ?8.2?kcal/mol toward the androgen receptor.     

Investigation of Spectroscopic Behaviors of Newly Synthesized (2E)-3-(3,4-Dimethoxyphenyl)-1-(2,5-dimethylthiophen-3-yl)prop-2-en-1-one (DDTP) Dye

This study introduced spectroscopic properties, physicochemical parameters, and polarity and photostability behaviors of a newly prepared chalcone dye. The chalcone dye, (2E)-3-(3,4-Dimethoxyphenyl)-1-(2,5-dimethylthiophen-3-yl)prop-2-en-1-one (DDTP), was synthesized by the reaction of 3,4-dimethoxybenzaldehyde with 3-acetyl-2,5-dimethythiophene. Results of FT-IR, ¹H-NMR, ¹³C-NMR and elemental analysis were in conformity with chemical structure of newly prepared DDTP. Data of thermal gravimetric analysis revealed that DDTP has good thermal stability. Increases in fluorescence intensities of DDTP with cetyltrimethyl ammonium bromide (CTAB) were observed. In comparison of fluorescence intensities for DDTP with CTAB, reductions in fluorescence intensities for DDTP with sodium dodecyl sulphate (SDS) were observed under the same experimental and instrumental conditions. Moreover, Benesi-Hildebrand method was applied to determine stoichiometric ratios and association constants of DDTP with CTAB and SDS. The stoichiometric ratio and association constant obtained from Stern-Volmer plot strongly supported those obtained from Benesi-Hildebrand plot of DDTP with SDS. Physicochemical parameters, such as, singlet absorption, molar absorptivity, oscillator strength, dipole moment and fluorescence quantum yield of DDTP were also estimated. Fluorescence steady-state measurements ultimately displayed that DDTP has a high photostability against photobleaching. Fluorescence polarity study revealed that DDTP was sensitive to the polarity of the microenvironment provided by different solvents.     

Room temperature synthesis of crystalline CeO2 nanopowder: advantage of sonochemical method over conventional method

In the present study, nano-sized ceria (CeO(2)) powders were prepared using conventional and sonochemically assisted precipitation method, without any stabilizers, using cerium nitrate as a starting material and sodium hydroxide as a precipitating agent. The synthesized ceria powders were characterized by XRD, TGA and SEM to determine crystallite size, % crystallinity, thermal weight loss and shape respectively. It was found that the crystallite size obtained in both the synthesis methods were below 30 nm. It was also found that sonochemical synthesis method is energy efficient method saving more than 92% of energy as compared to that utilized by the conventional synthesis method. There was also a significant reduction in the reaction duration.     

4-[(E)-2-(3, 4-二甲氧基苯基)乙烯基]苯氧基乙酸乙酯的合成及其NMR研究

以对硝基甲苯、3, 4-二甲氧基苯甲醛为起始原料,经过缩合,还原,重氮化水解,亲核取代反应,最终合成了新的化合物4-[(E)-2-(3, 4-二甲氧基苯基)乙烯基]苯氧基乙酸乙酯,用¹H 和¹³C NMR及多种二维核磁共振谱确定了该化合物的结构,完成了¹H 和¹³C NMR的归属,给出了分子中各氢,碳原子的准确化学位移.     

Sonochemical synthesis of a novel nanoscale 1D lead(II) [Pb2(L)2(I)4]n coordination Polymer,survey of temperature,reaction time parameters

One new lead(II) coordination supramolecular complex (CSC) (1D), [Pb₂(L)₂(I)₄]_n, L = C₄H₆N₂ (1-methyl imidazole), has been synthesized under different experimental conditions. Micrometric crystals (bulk) or nano-sized materials have been obtained depending on using the branch tube method or sonochemical irradiation. All materials have been characterized by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD) and FT-IR spectroscopy. Single crystal X-ray analyses on complex 1 showed that Pb²⁺ ion is 4-coordinated. Topological analysis shows that the complex 1 is 2,3,5C2 net. Finally, the role of reaction time and temperature on the growth and final morphology of the structures obtained by sonochemical irradiation have been studied.     

Ultrasound and deep eutectic solvent (DES): A novel blend of techniques for rapid and energy efficient synthesis of oxazoles

The present work deals with the synthesis of novel oxazole compounds by using effective combination of ultrasound (US) and deep eutectic solvent (DES). The reaction was also conducted by thermal method (NUS) and the comparative studies are provided. It was observed that applying ultrasound not only improved yields and reduced reaction times but also saved more than 85% energy as shown by energy consumption calculations. The advantages of using DES as reaction medium is highlighted from the fact that it is bio-degradable, non-toxic, recyclable and could be easily prepared using inexpensive raw materials. The recyclability for DES was studied wherein it was found that ultrasound has no negative effects on DES even up to four runs. In addition, the present work is the first report on the combinative use of DES and US in organic synthesis.     

1-(4-硝基苯氨基乙酰基)-4-苯乙酰基氨基硫脲的NMR谱研究

利用二维核磁共振技术,对所合成的新化合物1-(4-硝基苯氨基乙酰基)-4-苯乙酰基氨基硫脲的¹H NMR 和¹³C NMR谱进行了全归属.     

Synthesis,structural characterization,spectroscopic, thermal,dielectric and Hirshfeld surface analysis of 1-(2-methoxyphenyl)piperazinium chloranilate

The new compound 1-(2-methoxyphenyl)piperazinium chloranilate (MPP.CA) was synthesized and studied by the single crystal X-ray diffraction method. Its structure was confirmed by infrared spectroscopy. The crystal structure consists of ribbons of chloranilate anions and 1-(2-methoxyphenyl)piperazinium cations linked together by NH…O hydrogen bonds. Two protons are transferred from a chloranilic acid molecule to the nitrogen of the piperazine in this structure. Measurements of AC conductivity as a function of frequency at different temperatures indicated the hopping conduction mechanism; in addition, the variation of dielectric constant as a function of T confirmed the transition phase indicated by the differential scanning calorimetry (DSC). The physico-chemical properties, UV-Vis, DSC and dielectric properties are described. Hirshfeld surface analyzes all the intermolecular interactions involved within the structure, which are important to stabilize the structure.     

FT-IR, FT-Raman, NMR spectra and DFT simulations of 4-(4-fluoro-phenyl)-1H-imidazole

The FT-IR, FT-Raman and FT-NMR spectra of the compound 4-(4-Fluoro-phenyl)-1H-imidazole (4-FPI) were recorded and analyzed. Density functional method (B3LYP level with the 6–311G(d, p) and 6–311++G(d, p) and cc-pVQZ as basis sets) has been used to compute optimized geometry, vibrational wavenumbers of the 4-FPI. Only one tautomeric form was found most stable by using DFT/B3LYP. The detailed interpretation of the vibrational spectra was carried out with the aid of total energy distribution following the scaled quantum mechanical force field methodology. Potential Energy Surface scan studies has also been carried out by ab initio calculations with the same basis sets.     

4-氟苯甲醛酪氨酸席夫碱的制备及其振动光谱的密度泛函理论和从头算理论计算的研究

4-氟苯甲醛酪氨酸席夫碱(4-FT)由4-氟苯甲醛和L-酪氨酸钾盐在室温条件下反应制得,4-FT的结构通过1HNMR,FTIR和Raman测试得到确认。分别用密度泛函(DFT,density functional theory)理论的B3LYP(Becke’s three-parameter exchange functional(B3)with Lee,Yang,Parr(LYP))方法和从头算(ab initio)理论的HF(Hartree-Fock)方法,选用标准的6-31G**和6-31G*基组对化合物4-FT的几何构型进行优化。同时分别在B3LYP/6-31G**,B3LYP/6-31G*,HF/6-31G**和HF/6-31G*水平下计算4-FT的振动波数。用密度泛函(DFT)的B3LYP方法计算并校正后的波长数据比用从头算(ab i-nitio)的HF方法计算的结果更与实验数据吻合。     

A novel and convenient synthesis of 4-hydroxy-6-methyl-3-(1-(phenylimino) ethyl)-2H-pyran-2-one derivatives under ultrasound irradiation

A facile, efficient and environment-friendly protocol for the synthesis of 4-hydroxy-6-methyl-3-(1-(phenylimino)ethyl)-2H-pyran-2-one derivatives has been developed by the convenient ultrasound-mediated condensation of amine with dehydroacetic acid. This method provides several advantages over current reaction methodologies including a simple work-up procedure, shorter reaction times and higher yields.     

DFT simulations, FT-IR, FT-raman, and FT-NMR spectra of 4-(4-chlorophenyl)-1H-imidazole molecules

The FT-IR, FT-Raman and FT-NMR spectra of the compound 4-(4-Chlorophenyl)-1H-imidazole (4-ClPI) was recorded and analyzed. Density functional method has been used to compute optimized geometry, vibrational wavenumbers and NMR spectra of the 4-ClPI. Only one tautomeric form was found most stable by using B3LYP functional with the 6?C311++G(d,p) as basis sets. The detailed interpretation of the vibrational spectra was carried out with the aid of total energy distribution (TED) following the scaled quantum mechanical force field methodology.     

(E)-3-(4一羟苯基)-1-(哌啶-1-基)丙-2-烯-1-酮衍生物核磁共振特征与构象分析

设计并合成了一系列(E)-3-(4-羟苯基)-1-(哌啶-1-基)丙-2-烯-1-酮衍生物. 通过一维和二维核磁共振实验完成了¹H和¹³C信号的指认. 通过ROESY、变温实验和分子模拟技术对这类化合物的构象进行了分析.     

Ground- and excited-state spectroscopic studies on [1-(4-methoxyphenyl)-3-(amino)-2,4-(dicyano)-9,10-tetrahydrophenanthrene]

The effects of polar and nonpolar solvents on both the ground and the excited-state properties of [1-(4-methoxyphenyl)-3-(amino)-2,4-(dicyano)-9,10-tetrahydrophenanthrene] is examined. Light absorption results in a population of a locally excited (LE) first singlet state (S₁,n^*) which shows sensitivity to the polarity of the surrounding solvent and hydrogen-bonding ability to the quencher 4-methylpyridine. Relaxation of this state leads to an intramolecular charge-transfer state (ICT) which leads to a large Stokes shift in polar solvents and an excited-state dipole moment of _e= 10D. The quenching of the fluorescence state by 4-methylpyridine studied inn-hexane and acetonitrile at room temperature is found to be efficient and a positive deviation from linearity was observed in the Stern-Volmer plots even at concentrations of 4-methylpyridine below 0.4M. This is explained as a result of the occurrence of both a dynamic and a static quenching mechanism. The static quenching constants (K _sv) along with those obtained by visible spectroscopy (K _GS) indicate that the ground-state complex is weak and relatively solvent dependent.     

2-对二甲氨基苯基-5-氟-6-吗啉苯并咪唑的合成及其光谱学性质研究

合成了一种新的取代苯并咪唑化合物 ,2 对二甲氨基苯基 5 氟 6 吗啉苯并咪唑 ,采用紫外 可见光谱、荧光光谱及荧光寿命等方法探讨了溶液pH值对该化合物吸收光谱的影响及其与 β 环糊精的作用。结果表明 ,pH >7 0时 ,该化合物在溶液中主要以中性分子状态存在 ,当 3 8相似文献