Alcoholic Alkali Research Articles

Alcohol–alkali hydrolysis for high-throughput PET waste electroreforming-assisted green hydrogen generation

The solubility of PET waste bottles was improved to 91 g L−1 by alcohol–alkali combined depolymerization. Iron, cobalt co-modified nickel phosphide nanosheet arrays on nickel foam were used as a bifunctional electrocatalyst for PET hydrolysate electroreforming-assisted green hydrogen evolution.

Superhydrophobic lignin-based multifunctional polyurethane foam with SiO2 nanoparticles for efficient oil adsorption and separation

Superhydrophobic polyurethane foam is one of the most promising materials for oil-water separation. However, there are only limited studies prepared matrix superhydrophobic foams as adsorbents. In this paper, SiO2 modified by 1H, 1H, 2H, 2H-perfluorododecyl trichlorosilane (F-SiO2) was added into the lignin-based foam matrix by a one-step foaming technique. The average diameter of F-SiO2 was about 480 nm with an water contact angle (WCA) of 160.3°. The lignin-based polyurethane foam with F-SiO2 had a superhydrophobic water contact angle of 151.3°. There is no obvious change in contact angle after 100 cycles of compression or after cutting and abrasion. Scanning electron microscopy (SEM) analysis showed that F-SiO2 was distributed both on the surface and inside of the foam. The efficiency for oil-water separation reached 99 %. Under the light intensity of 1 kW/m2, the surface temperature of the lignin-based foam rose to 77.6 °C. In addition, the foam exhibited self-cleaning properties and degraded within 2 h in an alcoholic alkali solution. Thus, in this study, we developed a novel matrix superhydrophobic lignin-based polyurethane foam with an excellent promise to be used as oil water separation adsorbents in industrial wastewater treatment and oil spill clean-up processes.

Biological Evaluation of Some Novel Sulphur Substituted Chalcones as New Scaffold

In the past few decades, developing antifungal and anticancer agents has become essential in drug research. Cancer is one of the most challenging diseases in the world. Most reviews on chalcones suggested that substituted chalcones have numerous biological activities. This study aim includes synthesizing different Sulphur containing chalcones in the presence of para-amino acetophenone linked to various aldehydes in the presence of aqueous alcoholic alkali. The structural analysis of synthesized compounds was also carried out by IR, 1HNMR 13CNMR and MASS spectra. The docking study was performed by Biovia discovery studio 20202. Invitro cytotoxic activity was carried out by human breast cancer cell line MCF-7 using MTT assay. Antifungal activity was conducted by diffusion method against Candida albicans and Aspergillus niger. Novel synthesized compounds, especially BT-IV-A, BT-IV-B, BTIV- C, BT-IV-E and BT-IV-I showed significant antifungal activity as BT-IV-H, BT-IV-E, and T-IV-F revealed excellent growth-inhibitory impact for the development of new anticancer agents.

Novel Photosynthesis And Characterization of 4-(5,7- Dichloro-8ah-chromene-2-yl)-n, N-dimethylaniline from Its Chalcone Isomer

In the present study, trans-3-(2,4-dichlorophenyl)-1-(4-(dimethylamino)phenyl)prop-2-en-1-one (trans 2,4-dimethyl amino chalcone) was synthesized by Claisen-Schmidt reaction in the presence of aqueous alcoholic alkali solution by condensation of a substituted acetophenone with substituted benzaldehydes, Then, The photosynthesis of 4-(5,7-dichloro-8aH-chromen-2-yl)-N,N-dimethylaniline (2,4-dimethylamino chromene) was accomplished from the irradiation of the( trans 2,4-dimethyl amino chalcone) with xenon light. The products were characterized by UV-Visible, FT-IR, 1HNMR, thin layer chromatography Elemental analysis(CHNO) and liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-Q-ToF-MS).

Novel Photosynthesis of 5,8a-dichloro-2-(4- Methoxyphenyl)-8ah-chromene from Its Chalcone Isomer And Ft-ir, 1 H And 13 C Nmr Spectroscopic Investigation

In the presence of alcoholic alkali, the base-catalyzed aldol condensation of equimolar quantities of substituted acetophenones and aldehydes to give good yields of condensation product. This reaction is known as the Claisen-Schmidt condensation. The Trans-3-(2,6-dichlorophenyl)-1-(4-methoxyphenyl)prop- 2-en-1-one (trans 2,6-methoxy chalcone) was synthesised by Clasien Schmidt reaction, then it exposed to the Xenon lamp to prepare the 5,8a-dichloro-2-(4-methoxyphenyl)-8aH-chromene (2,6-methoxy chromene). A number of techniques were used to characterise the mentioned two products such as, thin layer chromatography, FT-IR, 1H and 13C nuclear magnetic resonance, liquid chromatography/quadrupole time-of-flight mass spectrometry and elemental analysis (CHNO).

Behaviour of pancreatic lipase enzyme during recyclization when synthesizing butyl butyrate in non-aqueous media

Aromatic substances are widely applied in the creation of fragrances for cosmetic, detergent and food products, as well as medical preparations for external use. Environmentally friendly enzymes obtained using green chemistry methods are of particular value. Therefore, the enzymatic synthesis of esters of aromatic aliphatic acids and aromatic alcohols is of great practical interest. This approach has significant advantages over chemical methods, since it is carried out at low temperatures without the formation of byproducts, thus requiring no special purification techniques. Although the cost of enzyme preparations is rather high, immobilized enzymes can be used repeatedly and continuously. In the present work, we investigate the possibility of using non-immobilized freeze-dried lipase (Lipase from porcine pancreas, Type 11) for repeated esterification of butyl alcohol with butyric acid. The synthesis was carried out in hexane. The completeness of the process was controlled by titration of the residual acid with aqueous alcoholic alkali in the reaction medium. The resulting enzyme preparation was separated from the reaction mixture and reused with a new portion of the substrate. It is shown that the obtained enzyme can be used for more than 10 cycles. It was found that, starting from the second cycle, the enzyme activity increases depending on its concentration in the medium. In addition, the butyric acid conversion increases by 6–180% reaching the initial level only after the 10th cycle. The unusual effect of increasing the enzymatic activity of lipase in recycles can be explained by both the phenomenon of autocatalysis, i.e. activation of the enzyme by water released as a result of esterification, and structural features of the active site of pancreatic lipase.

Study of the Composition of the Fuel Used in a Lamp from an Ancient Settlement from the Taman Peninsula

The paper presents the results of an analysis of organic residue found at the bottom of an ancient lamp discovered during excavations at the Akhtanizovskaya 4 settlement (Krasnodar krai, Temryukskii district, northeastern outskirts of the Akhtanizovskaya village) in the cultural layer of the first century BC. Samples of the residue from the bottom of the lamp were extracted with a solvent mixture by the Folch method and treated with an alcoholic alkali solution. The extracts were then subjected to derivatization to obtain fatty acid methyl esters, the quantitative and qualitative compositions of which were determined by gas chromatography. The plant oil admixture found in the residue from the lamp was identified by analyzing sterol content by chromatography-mass spectrometry. The obtained results revealed that the fuel composition consisted of beef fat and rapeseed oil.

Structural Characterization of Controlled Decrystallization of Cassava Starch

AbstractNative starch granule has a complex crystalline structure. Controlled decrystallization cassava starch (CDCS) was prepared by the alcohol–alkali method. Polarized microscopy, scanning electron microscopy (SEM), X‐ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) analysis of the CDCS are carried out to investigate its structural information. The results show that the relative crystallinity (RC) of the processed cassava starches can be reduced from 25.56% to 17.90% by adjusting the concentration of sodium hydroxide while keeping the integrity of the starch granule. During the decrystallization process, as the sodium hydroxide concentration is increased from 0.25 to 1.25 mol L−1, the polarized light of the starch granules disappear from the inside to the outside, and the X‐ray diffraction peaks of native cassava starch (NCS) disappear sequentially from 17.16°, 23.04°, 15.08°, to 17.83°. On the other hand, the FTIR peaks of the NCS centered at 1645 cm−1 is shifted to about 1600 cm−1, and the intensity of the peaks at 3424, 2929, 1645, and 1017 cm−1 become weaker with decrystallization process. This study provides valuable data and a theoretical basis to understand the mechanism of the controlled decrystallization of cassava starch.

Thermal Properties of Salt and Base Forms of Chitosan

The temperature dependences of elastic and relaxation properties of films of salt and base forms of chitosan were obtained by methods of dynamic mechanical analysis. It was estimated that the presence of two maxima on the temperature dependence of mechanical loss tangent tanδ at T1 = 150–160°C and T2 = 250–270°C is typical of the salt form of chitosan. The maximum at 150–160°C on tanδ curves is reduced or even eliminated after thermal or alcohol–alkali treatment of chitosan acetate films, while the high-temperature maximum is preserved. The results of IR spectroscopy and thermogravimetric analysis allow supposing that the low-temperature maximum of molecular mobility in films of chitosan salt form is related to the removal of absorbed water and residues of acetic acid as well as to dehydration of macromolecules. The maximum at 259°C determines the glass transition temperature of the chitosan base form.

Recycling and depolymerization of waste polyethylene terephthalate bottles by alcohol alkali hydrolysis

In this work, a novel alcohol alkali hydrolysis method was explored for the preparation of terephthalic acid (TPA) from waste polyethylene terephthalate (PET). First, a series of single factor experiments on the depolymerization rate of waste PET bottles and the yield of TPA were conducted to determine the optimized experimental conditions, in terms of reaction time, reaction temperature, dosage of ethylene glycol and sodium bicarbonate, amount of distilled water and stirring rate. Then IR spectra and elemental analysis were carried out for the characterization of obtained product. Under optimal experimental conditions, over 98% PET can be depolymerized into the target product (TPA) and the purity and yield of TPA are over 97% and 94%, respectively. Both the experimental and analytical results support a feasible process for the preparation of TPA from waste PET. It is expected that this alcohol alkali hydrolysis method can promise an effective way for the sustainable recycling of waste PET.

Determination of benzo[a]pyrene in edible oils using phase-transfer-catalyst-assisted saponification and supramolecular solvent microextraction coupled to HPLC with fluorescence detection.

For the analysis of edible oils, saponification is well known as a useful method for eliminating oil matrices. The conventional approach is conducted with alcoholic alkali; it consumes a large volume of organic solvents and impedes the retrieval of analytes by microextraction. In this study, a low-organic-solvent-consuming method has been developed for the analysis of benzo[a]pyrene in edible oils by high-performance liquid chromatography with fluorescence detection. Sample treatment involves aqueous alkaline saponification, assisted by a phase-transfer catalyst, and selective in situ extraction of the analyte with a supramolecular solvent. Comparison of the chromatograms of the oil extracts obtained by different microextraction methods showed that the supramolecular solvent has a better clean-up effect for the unsaponifiable matter from oil matrices. The method offered excellent linearity over a range of 0.03- 5.0 ng mL-1 (r > 0.999). Recovery rates varied from 94 to 102% (RSDs <5.0%). The detection limit and quantification limit were 0.06 and 0.19 μg kg-1 , respectively. The proposed method was applied for the analysis of 52 edible oils collected online in China; the analyte contents of 23 tested oil samples exceeded the maximum limit of 2 μg kg-1 for benzo[a]pyrene set by the Commission Regulation of the European Union.

A Novel and Efficient Synthesis of Momelotinib

An improved route for the synthesis of momelotinib has been developed. A nucleophilic addition reaction between the starting material, 4-morpholinoaniline, and cyanamide gave the 1-(4-morpholinophenyl)guanidine. Simultaneously, methyl 4-acetylbenzoate was converted into methyl ( E)-4-[3-(dimethylamino)acryloyl]benzoate in the presence of N,N-dimethylformamide dimethylacetal. The enaminone intermediate was then condensed at elevated temperature in alcoholic alkali with the 1-(morpholinophenyl)guanidine to form the desired pyrimidine, which was hydrolysed to the corresponding acid. This procedure is simple in operation, without noble metal catalyst and suitable for industrial production. Finally, the desired compound momelotinib was acquired by an amidation reaction.

Antioxidant Activities and the In Vitro Effects on K562 Cell Viability of Flavonoids Obtained from Onion Skin by Different Extraction Methods

In order to effectively extract specific flavonoids with high biological activity from onionskin, NaNO2- Al(NO3)3-NaOH coloration method, spectrophotometry and MTT method were adopted to study the yield rate and content of flavonoids obtained from alcohol water and alkali water extraction processes, the antioxidant activities and the in vitro effects on K562 cell viability. The results indicated that yield rates of flavonoids obtained by alcohol water and alkali water extraction methods were 3.76% and 2.37%, and solid flavonoids contents were 42.20% and 76.21% respectively; under the same concentration of total flavonoids, alkali water extract has weaker effect on removing superoxide anions and DPPH • radicals, whereas they have similar effect on removing nitrite and hydroxyl free radicals; in the test concentration range (40 ∼ 200 µg / mL), they have similar effect on inhibiting the proliferation activity of K562 cells; the maximum inhibition rate of flavonoids obtained by alkali water extraction method is 77.71%, while maximum inhibition rate of flavonoid obtained by alcohol water extraction method is 70.64%. Both the flavonoids obtained from onionskins by alcohol water extraction method and alkali water extraction method have good biological activity. The alkali water extraction method is simple and without any alcohol consumption, and the product purity is high. Although the yield rate and certain biological activity of flavonoids obtained by alkali water extraction method are lower than those obtained by alcohol water extraction method, it still has certain significance in industrial production.

Diazotization and formylation of 7-amino-3-tert-butyl-8-R-pyrazolo[5,1-c][1,2,4]triazin-4(6H)-ones

We previously synthesized 7-amino-3-tert-butyl-4oxo-4,6-dihydropyrazolo[5,1-c][1,2,4]triazine-8-carbonitrile (I) and the corresponding ethyl ester II by reaction of 4-amino-6-tert-butyl-3-methylsulfanyl-1,2,4triazin-5(4H)-one with malononitrile and ethyl cyanoacetate, respectively, in pyridine [3]. Heating of nitrile I in alcoholic alkali gave amide III in a good yield [4]. The reactivity of compounds I–III toward carbonyl compounds was studied, and the corresponding derivatives at the amino group and pyrimido[4′,5′ : 3,4]pyrazolo[5,1-c][1,2,4]triazines were thus obtained [3–5]. The goal of the present work was to examine the reactivity of the amino group in compounds I–III.

Synthesis, Characterization and Biological Evaluation of Some Novel Chalcone Derivatives Containing Imidazo[1,2-a] Pyridine Moiety

Chalcone was prepared by the condensation of arylmethyl ketone and arylaldehyde in the presence of alcoholic alkali. Present study describes the synthesis of a series of (2z)-3-(2-(4-chlorophenyl)-8-methyl imidazo(1,2-a) pyridine-3-yl)-1-substituted arylprop-2-en-1-one compounds (h) 1-9. The compounds were characterized by modern analytical techniques such as CHN analyses, IR, 1 H NMR spectra and further supported by mass spectroscopy. All the title compounds were screened for their in vitro antibacterial and antifungal activity against B.coccus, S.aureus, Pseudomona, E.coli, A.niger, Ampicillin, Amoxicillin, Ciprofloxacin, Norfloxacin, Greseofulvin. Their minimum inhibitory concentrations (MIC) were determined. The results of antibacterial activity showed that compounds h 4, h 9 and antifungal activity compounds h 1, h 9 using standard drug.

Cold-water in situ dissolution of bamboo starch in a bioreactor: inducing forest recovery from an anthropogenic disturbance

Using young forest trees as the source for timber, yam sticks have in recent years produced record rates of deforestation in Jamaica and, reportedly, in Western Africa and Southeast Asia. Regeneration periods for plants producing timber yam sticks (which decompose after 2 years) are approximately 10 years compared to 3–4 years for bamboo. But when used as a yam stick, bamboo decomposes even more rapidly and hence is unsatisfactory. For treatment (a), four 7-day periods of submergence in cold, stagnant water removed carbohydrates including starch. This increased the longevity of yam sticks from 5–7 months (untreated) to a period exceeding 2 years. Treatment (b) excluded soaking, and after slow-drying, a surface coating of polyurethane was applied. This treatment marginally increased longevity. It was concluded that alcoholic alkali conditions in the stagnant cold water increased bamboo yam stick longevity by dissolving and removing the main nutrient for decomposers, namely starch. Further, lateral struts on the bamboo yam sticks substantially increased tuber yields by exposing more leaves to direct sunlight. The incentive of increased tuber yields for farmers, the improved longevity of bamboo yam sticks, and the relatively rapid growth of bamboo promises an effective tool for curbing deforestation caused by yam stick harvesting.

Preparation of cold water-soluble potato starch and its characterization

Alcoholic-alkaline treatment of starch results in granular cold water-soluble starch. The nature of structural alterations occurred in starch due to the treatment is however relatively vague. Potato starch was treated at various alcoholic-alkali conditions and subjected to light microscopy, Fourier transform infrared (FTIR) spectroscopy and X-ray diffractometry. Alcoholic-alkaline treatment increased the solubility of starch in a temperature-dependant manner. The treated starch suspension was also more turbid than that of native counterpart at all concentrations, due probably to either the presence of higher number of water-soluble granules or leaching of amylose during alkalization. Alcoholic-alkali treating of starch did not disintegrate the granular assembly; albeit, decreased the crystalinity. Both native and treated starches showed the B-type pattern in X-ray diffractometry. FTIR spectroscopy revealed that characteristic peaks of hydroxyl groups were of low transmittance in spectrum of treated starch compared with that of native counterpart implying in participation of hydroxyl groups in interactions with modifying agents.

Bromination-dehydrobromination/debromination of N-Methyl-N-(2-phenylethenyl)trifluoromethanesulfonamide

We have recently synthesized the first N-alkenylsubstituted trifluoromethanesulfonamide, N-methyl-N[(E)-2-phenylethenyl]trifluoromethanesulfonamide (I) [1]. With a view to obtain new trifluoromethanesulfonamide derivatives, we tried to synthesize adducts of I with various nucleophiles. However, compound I failed to react with methanol, ethanol, or diethylamine even on prolonged heating under reflux, but it readily took up bromine molecule in dioxane, and the resulting dibromo derivative readily underwent dehydrobromination by the action of alcoholic alkali (Scheme 1). 10.9 Hz), and a doublet at δ 6.58 ppm (J = 9.5 Hz) with a lower intensity. The intensity of the signal at 5.15 ppm was equal to the overall intensity of the signals at δ 6.51 and 6.58 ppm; the intensity ratio of the major and minor downfield signals was about 8 : 1. Assuming that the signal at δ 5.15 ppm is a superposition of two doublets corresponding to the downfield signals at δ 6.51 and 6.58 ppm, we can conclude that adduct II is a mixture of two diastereoisomers at a ratio of 8 : 1. These findings are consistent with the presence in the F NMR spectrum of II of two signals at δF –73.95 and –72.46 ppm with the same intensity ratio. Insofar as initial compound I is trans isomer [1], the major product should be stereoisomer IIa in agreement with the generally preferred trans-addition pattern. This is also supported by the results of HF/6-311G** calculations [2], according to which the energy of isomer IIa is lower by 1.3 kcal/mol than that of IIb. ISSN 1070-4280, Russian Journal of Organic Chemistry, 2013, Vol. 49, No. 6, pp. 924–926. © Pleiades Publishing, Ltd., 2013. Original Russian Text © I.V. Ushakova, B.A. Shainyan, 2013, published in Zhurnal Organicheskoi Khimii, 2013, Vol. 49, No. 6, pp. 938–939.

Synthesis, Characterization and Glass Reinforcement of Dimethylolurea-3-AminoPhenol-Epoxy Resin Curing Systems

N,N′-Dimethylolurea (DMU) was prepared and condensed with 3-aminophenol (AP) in the presence of alcoholic alkali catalyst at varying mole ratios of DMU: AP. The resultant dimethylolurea-3-aminophenol (DMUAP) resins were characterized. DMUAP-epoxy curing systems have been prepared by mixing DMUAP and epoxy resin (DGEBA) in different proportions. The curing study of DMUAP-epoxy systems was monitored on DSC and kinetic parameters were evaluated. Based on DSC data, glass-reinforced composites of DMUAP-epoxy systems have been laminated and characterized. The unreinforced cured material of DMUAP-epoxy systems were analyzed by thermogravimetric analysis (TGA).

APPLICATION OF OPTIMIZATION TECHNIQUE IN SYNTHESIS AND CHARACTERIZATION OF SODIUM CARBOXY ETHYL GUAR.

Guar gum is a galactomannan polysaccharide obtained from the dried ripe seeds of Cyamopsis tetragonolobus. The objective of the present study was to derivatise guar gum to SCEG and to overcome limitations of guar gum viz, susceptible to microbial contamination, fall in viscosity on storage and to form a clear aqueous dispersion without imparting color to the formulation. The semisyntheic derivative of SCEG obtained by alcoholic alkali suspension method of guar gum was tried by applying optimization technique (32 factorial design) by altering the 2-chloropropionic acid:guar gum, percentage w/v ratio NaOH and temperature of the reaction mixture. The optimized polymer obtained from the various trials was subjected to physical, chemical and spectral characterization. Characterization revealed that derivatization of the guar gum to sodium carboxy ethyl guar. The derivatised polymer exhibited high stability at all ranges of temperature (50C, 250C, 370C and 450C), controlled rate of hydration, pseudoplastic flow pattern and less susceptibility to microbial contamination. Sodium carboxy ethyl guar solution is more controllable than gaur gum with regard to its thickening, viscosity building, suspending, film forming and excipent in the matrix tablets. The valid application of optimization technique was found to be highly productive in achieving an effective semisynthetic derivative meeting the ideal requirements.