Reactions最新文献_第9页

Synthesis and Characterization of Multiple Functionalized Cyclohexanone Using Diels–Alder Reaction of α-Nitrocinnamate α-硝基氨基酸酯diols - alder反应合成多功能化环己酮及表征

Reactions Pub Date : 2022-12-02 DOI: 10.3390/reactions3040041

Takumi Hamada, Kento Iwai, N. Nishiwaki

引用次数: 0

Selective O-alkylation of Phenol Using Dimethyl Ether 二甲醚选择性邻烷基化苯酚

Reactions Pub Date : 2022-11-17 DOI: 10.3390/reactions3040040

Mane Samruddhi, Akash Bhatkar, M. Prabu, S. Mekala, P. Gogoi, G. Mohapatra, Raja Thirumalaiswamy

{"title":"Selective O-alkylation of Phenol Using Dimethyl Ether","authors":"Mane Samruddhi, Akash Bhatkar, M. Prabu, S. Mekala, P. Gogoi, G. Mohapatra, Raja Thirumalaiswamy","doi":"10.3390/reactions3040040","DOIUrl":"https://doi.org/10.3390/reactions3040040","url":null,"abstract":"Anisole is a straw-colored aromatic compound mainly used in making solvents, flavoring agents, perfumes, fuel additives, and in the synthesis industries. Anisole, also known as methoxybenzene, is synthesized from sodium phenoxide or phenol using various methylating agents. The use of dimethyl ether (DME) as an alkylating agent is seldom reported in the literature. Herein, we have synthesized anisole through the O-alkylation process of phenol and DME to obtain zero discharge from this process. The thermodynamic equilibrium for the reaction of phenol and DME is simulated by using Aspen HYSYS (Hyprotech and Systems). The O-alkylation of phenol has been investigated using phosphotungstic acid (PTA) over γ-Al2O3 with appropriate acidity. Active metal loadings of various percentages were studied and the conversion was optimized at 46.57% with a selectivity of 88.22% at a temperature of 280 °C. The liquid products from the continuously stirred reactor were analyzed with liquid G.C. and the conversion and selectivity were calculated. A comparison of the O-alkylation and C-alkylation of phenol at different temperatures, reactant ratios, residence times, and recyclability was explored, as well as the impact of these factors on the yield of the desired anisole. The catalyst was characterized by XRD, BET, HR-TEM, FE-SEM, elemental mapping, XPS, and DRIFT studies.","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81890282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hydrolytic Oxidation of Cellobiose Using Catalysts Containing Noble Metals 含贵金属催化剂水解氧化纤维素二糖的研究

Reactions Pub Date : 2022-11-16 DOI: 10.3390/reactions3040039

O. Manaenkov, O. Kislitsa, E. Ratkevich, Yu. Kosivtsov, V. Sapunov, V. Matveeva

{"title":"Hydrolytic Oxidation of Cellobiose Using Catalysts Containing Noble Metals","authors":"O. Manaenkov, O. Kislitsa, E. Ratkevich, Yu. Kosivtsov, V. Sapunov, V. Matveeva","doi":"10.3390/reactions3040039","DOIUrl":"https://doi.org/10.3390/reactions3040039","url":null,"abstract":"Studies of the processes of the hydrolytic oxidation of disaccharides are the first step towards the development of technologies for the direct conversion of plant polysaccharides, primarily cellulose, into aldonic and aldaric acids, which are widely used in chemical synthesis and various industries. In this study, heterogeneous catalysts based on a porous matrix of hypercrosslinked polystyrene (HPS) and noble metals (Pt, Au, Ru, and Pd) were proposed for the hydrolytic oxidation of cellobiose to gluconic and glucaric acids. The catalysts were characterized using low-temperature nitrogen adsorption, hydrogen chemisorption, electron microscopy, and other methods. In particular, it was shown that the Pt-containing catalyst contained, on average, six times more active centers on the surface, which made it more promising for use in this reaction. At a temperature of 145 °C, an O2 pressure of 5 bars, and a substrate/catalyst weight ratio of 4/1, the yields of gluconic and glucaric acids reached 21.6 and 63.4%, respectively. Based on the data obtained, the mathematical model of the cellobiose hydrolytic oxidation kinetics in the presence of 3% Pt/HPS MN270 was developed, and the parameter estimation was carried out. The formal description of the kinetics of cellobiose hydrolytic oxidation was obtained.","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91266695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Decomposition of Heavy Diesel SCR Urea Fluid Adsorbed in Cu/HZSM-5 SCR Catalysts Studied by FTIR Spectroscopy at Ambient Conditions 常压条件下Cu/HZSM-5 SCR催化剂吸附重柴油SCR尿素液分解研究

Reactions Pub Date : 2022-11-11 DOI: 10.3390/reactions3040038

C. Tempelman, Brahim el Arkoubi, Jochem Spaan, Ronny Slevani, V. Degirmenci

{"title":"Decomposition of Heavy Diesel SCR Urea Fluid Adsorbed in Cu/HZSM-5 SCR Catalysts Studied by FTIR Spectroscopy at Ambient Conditions","authors":"C. Tempelman, Brahim el Arkoubi, Jochem Spaan, Ronny Slevani, V. Degirmenci","doi":"10.3390/reactions3040038","DOIUrl":"https://doi.org/10.3390/reactions3040038","url":null,"abstract":"A method is presented to study the decomposition of urea deposited on Cu/HZSM-5 SCR catalysts and therewith the ability of the Cu/HZSM-5 SCR catalyst to be regenerated when being overdosed with SCR urea fluids during operation. This straightforward laboratory method could speed up calibration of exhaust gas aftertreatment systems. As an example, the removal of adsorbed urea to the SCR substrate due to dosage malfunction is studied. To study the removal of adsorbed urea on the catalyst substrate, FTIR experiments have been conducted to investigate the state of the catalyst. Besides Cu/HZSM-5 also HZSM-5 and CuOx were studied as model compounds to provide more inside on the processes occurring at the Cu/HZSM-5 surface upon urea decomposition. To simulate exposure of the SCR catalyst to overdosing of the urea solution, samples were impregnated with a 32 wt% urea solution, which correlates to that of commercial heavy duty diesel urea solutions. After impregnation, the samples were heated at various temperatures in the 133–400 °C temperature region, typically the operation window of a SCR catalyst. After heating, the samples were cooled to room temperature and measured in FTIR. The obtained spectra were compared with various literature reports to correlate the observed absorption bands to urea, urea related compounds and decomposition compounds. The concentration of these adsorbed species decreases at increased thermolysis temperature and is no longer visible at temperatures >250 °C. Extended heat treatment at 200 °C revealed only minor loss of adsorbents after 6 h and were still observable in the FTIR spectra after 24 h. Urea derived adsorbents were completely removed when simulating catalyst regeneration under SCR operation conditions under continuous air flow with a humidity of 10% and at elevated temperatures (400 °C).","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"131 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79386085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Azathioprine overdose* 用药过量*

Reactions Pub Date : 2022-11-01 DOI: 10.1007/s40278-022-27485-y

引用次数: 0

Valproic acid 丙戊酸

Reactions Pub Date : 2022-11-01 DOI: 10.1007/s40278-022-27937-6

引用次数: 0

Preliminary Studies on the Electrochemical Conversion of Liquefied Forest Biomass 液化森林生物质电化学转化的初步研究

Reactions Pub Date : 2022-10-31 DOI: 10.3390/reactions3040037

Tiago Silva, José Condeço, D. Santos

{"title":"Preliminary Studies on the Electrochemical Conversion of Liquefied Forest Biomass","authors":"Tiago Silva, José Condeço, D. Santos","doi":"10.3390/reactions3040037","DOIUrl":"https://doi.org/10.3390/reactions3040037","url":null,"abstract":"Bio-oils produced from three different biomass sources, namely cork, pinewood, and olive stones, are evaluated concerning their suitability and prospects of including their electrochemical transformations in a biorefinery scenario for the production of added-value compounds. Different types and concentrations of electrolytes (e.g., H2SO4, KOH) are added to the bio-oils to increase the samples’ initially low ionic conductivity. The samples prepared by mixing bio-oil with 2 M KOH aqueous solution (50 vol.%) lead to a stable and homogeneous bio-oil alkaline emulsion suitable for electrochemical studies. The bio-oil samples are characterized by physicochemical methods (e.g., density, viscosity, conductivity), followed by analyzing their electrochemical behavior by voltammetric and chronoamperometric studies. The organics electrooxidation and the hydrogen evolution reaction in the bio-oils are assessed using Pt electrodes. Single- and two-compartment cell laboratory bio-oil electrolyzers are assembled using nickel plate electrodes. Electrolysis is carried out at 2.5 V for 24 h. Attenuated Total Reflection-Fourier-Transform Infrared Spectroscopy and Mass Spectrometry are applied to identify possible changes in the bio-oil samples’ chemical structure during the electrolysis experiments. Comparing the analyses of the bio-oil samples subjected to electrolysis with the blank samples demonstrates that bulk electrolysis significantly changes the bio-oil composition. The bio-oil obtained from cork biomass shows the most promising results, but further studies are required to understand the nature of the actual changes.","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84960138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Greener and Efficient Epoxidation of 1,5-Hexadiene with tert-Butyl Hydroperoxide (TBHP) as an Oxidising Reagent in the Presence of Polybenzimidazole Supported Mo(VI) Catalyst 在多苯并咪唑负载的Mo(VI)催化剂存在下，以过氧化叔丁基(thbhp)为氧化试剂更环保高效地环氧化1,5-己二烯

Reactions Pub Date : 2022-10-21 DOI: 10.3390/reactions3040036

M. M. R. Bhuiyan, M. Mohammed, B. Saha

{"title":"Greener and Efficient Epoxidation of 1,5-Hexadiene with tert-Butyl Hydroperoxide (TBHP) as an Oxidising Reagent in the Presence of Polybenzimidazole Supported Mo(VI) Catalyst","authors":"M. M. R. Bhuiyan, M. Mohammed, B. Saha","doi":"10.3390/reactions3040036","DOIUrl":"https://doi.org/10.3390/reactions3040036","url":null,"abstract":"Alkene epoxidation with TBHP as an oxidising reagent using heterogeneous Mo(VI) catalyst is an environmentally friendly process since it eliminates acid waste and chlorinated by-products often associated with the conventional industrial method that uses stoichiometric peracid such as peracetic acid and m-chloroperbenzoic acid. Polybenzimidazole supported Mo(VI) complex, i.e., PBI.Mo has been successfully prepared, characterised and assessed for the epoxidation of 1,5-hexadiene in the presence of tert-butyl hydroperoxide (TBHP) as an oxidising reagent. A quadratic polynomial model has been developed, demonstrating the yield of 1,2-epoxy-5-hexene in four independent variables. The effects of different parameters such as reaction temperature, feed mole ratio of 1,5-hexadiene to TBHP, catalyst loading, and reaction time were studied. Response surface methodology (RSM) using Box-Behnken Design (BBD) was employed to study the interaction effect of different variables on the reaction response. This study presents the optimization of 1,5-hexadiene epoxidation in a batch reactor using TBHP as an oxidant and a polymer-supported Mo(VI) catalyst.","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84261590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Measuring Kinetics in Flow Using Isoperibolic Flow Calorimetry 用等循环流量量热法测量流动动力学

Reactions Pub Date : 2022-10-12 DOI: 10.3390/reactions3040035

T. Frede, Moritz Greive, N. Kockmann

引用次数: 2

Microwave-Assisted Synthesis of Tri-Substituted 1,3,5-Triazines from Metformin Using Benzotriazole Chemistry 苯并三唑化学微波辅助二甲双胍合成三取代1,3,5-三嗪

Reactions Pub Date : 2022-10-04 DOI: 10.3390/reactions3040034

S. Panda, Eyana Thomas, Ashley M. Pham

引用次数: 2