Current Microwave Chemistry最新文献

{"title":"Microwave-assisted C-C, C-O, C-N, C-S bond formation and multicomponent reactions using magnetic retrievable nanocatalysts","authors":"Manavi Yadav, Mahima Dutta, Pema Tanwar, Reena Jain, Anju Srivastava, Ranjan Sharma","doi":"10.2174/2213335608666210804144559","DOIUrl":"https://doi.org/10.2174/2213335608666210804144559","url":null,"abstract":"\u0000\u0000Microwave-assisted organic synthesis has been perceived as one of the most powerful and sustainable tools to accomplish expeditious organic synthesis through a greener way on account of its specific features including targeted heating, reaction homogeneity, rapidity, possible modifications of activation parameters, improved selectivity, yield and purity, along with simpler work-up. Another rapidly growing field for the development of green and sustainable protocol is the application of the magnetic nanocatalysts. They not only meet the need for facile recovery from the reaction media after completion of a reaction but also provide the best attributes of nanotechnology along with the elimination of auxiliary substances and catalyst loss, thereby, making the overall process clean, fast and cost-effective. Thus, the amalgamation of magnetic nanocatalysts and microwave irradiation present an ideal blend for the development of sustainable methods in synthetic organic chemistry. Amidst various bond forming reactions, carbon-carbon (C–C) and carbon-heteroatom (C-X, where X= O, N, S) bond formations are essentially used to devise privileged molecular scaffolds for synthetic organic and medicinal chemistry. This review gives a succinct overview of the synthesis and application of various modified magnetic nanocomposites as task-specific catalysts for microwave assisted C-C and C-X bond formation reactions in recent years. (This review consists of more than 190 references)\u0000\u0000\u0000","PeriodicalId":43539,"journal":{"name":"Current Microwave Chemistry","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44444212","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}

{"title":"Meet The Editorial Board Member","authors":"D. Bogdał","doi":"10.2174/221333560802211028163158","DOIUrl":"https://doi.org/10.2174/221333560802211028163158","url":null,"abstract":"","PeriodicalId":43539,"journal":{"name":"Current Microwave Chemistry","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41605136","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}

{"title":"Microwave-assisted Carbon-Carbon and Carbon-Heteroatom Bond Forming Reactions - Part 2A (Part 1)","authors":"B. Banerjee","doi":"10.2174/221333560802211028163413","DOIUrl":"https://doi.org/10.2174/221333560802211028163413","url":null,"abstract":"","PeriodicalId":43539,"journal":{"name":"Current Microwave Chemistry","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48511750","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}

{"title":"Preface","authors":"Jerry J. Wu","doi":"10.2174/221333560801210603090513","DOIUrl":"https://doi.org/10.2174/221333560801210603090513","url":null,"abstract":"","PeriodicalId":43539,"journal":{"name":"Current Microwave Chemistry","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44960259","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}

{"title":"Meet The Editorial Board Member","authors":"Elisabete Clara Bastos Do Amaral Alegria","doi":"10.2174/221333560801210603090602","DOIUrl":"https://doi.org/10.2174/221333560801210603090602","url":null,"abstract":"","PeriodicalId":43539,"journal":{"name":"Current Microwave Chemistry","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43372061","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}

{"title":"Microwave-assisted organic synthesis in Water","authors":"Geetanjali, Ram Singh","doi":"10.2174/2213335608666210623151121","DOIUrl":"https://doi.org/10.2174/2213335608666210623151121","url":null,"abstract":"\u0000\u0000Most of the traditional methods for organic synthesis have been associated with environmental concern. The transition from traditional to modern methods of synthesis is mainly based on principles of green chemistry to achieve better sustainability by reducing the negative impact on the environment and health. It has been found that microwaves as an energy source in organic synthesis have a great advantage over conventional heating. Microwave-assisted reactions are energy efficient and hence, brought themselves in the preview green chemistry principles. The use of safer solvents is another important principle of green chemistry. The use of water as a solvent in organic synthesis has great benefits over the use of hazardous organic solvents in terms of environment and safety. This study will cover the use of both microwave and water simultaneously in organic reactions.\u0000","PeriodicalId":43539,"journal":{"name":"Current Microwave Chemistry","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45294305","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}

{"title":"Synthesis and Pharmacological Activities of Oxadiazole and Pyrimidine Bearing Thiocoumarin Derivatives","authors":"Monika R. Tiwari, N. Patel","doi":"10.2174/2213335608666210401152153","DOIUrl":"https://doi.org/10.2174/2213335608666210401152153","url":null,"abstract":"\u0000\u0000The study aims to synthesize thiocoumarin scaffolds clubbed with pyrimidine\u0000and 1,3,4-oxadiazole ring system under microwave irradiation and describe their pharmacological\u0000activities.\u0000\u0000\u0000\u0000We report herein an efficient and simple Lewis acid-catalyzed procedure for the\u0000synthesis of novel series of thiocoumarin clubbed with pyrimidine and 1,3,4-oxadiazole motifs\u0000under microwave irradiation. The microwave-assisted technique has many advantages, such as a\u0000higher yield, a clean and selective procedure, shorter reaction time, and simple work-up.\u0000\u0000\u0000\u0000The objective of the present study is to design and synthesize thiocoumarin scaffolds\u0000clubbed with pyrimidine and 1,3,4-oxadiazole ring system by microwave-assisted heating. Our\u0000prime focus is to highlight the synthetic approach developed for the synthesis of heterocyclic moieties\u0000of pharmacological interest, and the prominence has also been given to distinct advantages\u0000provided by microwave heating.\u0000\u0000\u0000\u0000 Thiocoumarin clubbed with pyrimidine, and 1,3,4-oxadiazole motifs was synthesized\u0000under microwave irradiation. All the synthesized molecules were evicted by IR, 1H NMR, 13C\u0000NMR, and mass spectra. The anti-microbial activity of synthesized compounds was examined\u0000against two Gram-negative bacteria (E. coli, P. aeruginosa), two Gram-positive bacteria (S. aureus,\u0000S. pyogenes), and three fungi (C. albicans, A. niger, A. clavatus) using the MIC (Minimal Inhibitory\u0000Concentration) method, anti-tubercular activity H37Rv using L. J. Slope Method and anti-\u0000oxidant activity using DPPH and ABTS bioassay method.\u0000\u0000\u0000\u0000The application of microwave technology for the rapid synthesis of biologically significant\u0000thiocoumarin analogues is very promising because of its shorter reaction time and higher\u0000yield. Some of these new derivatives showed moderate to good in-vitro anti-bacterial, anti-fungal,\u0000and anti-tubercular activity. Compounds B4 and B7 appeared to have high radical scavenging efficacies\u0000as 35.32 ± 0.446 and 33.97 ± 1.069 μg/mL ± SD of IC50 values in DPPH and ABTS bioassay,\u0000respectively.\u0000\u0000\u0000\u0000Microwave-assisted synthesis provides an implicit way to discover a promising class\u0000of molecular entities for the development of new anti-microbial and anti-oxidant agents. Oxadiazole\u0000and pyrimidine bearing thiocoumarin derivatives showed improved anti-microbial, antitubercular,\u0000and anti-oxidant activity.\u0000","PeriodicalId":43539,"journal":{"name":"Current Microwave Chemistry","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42220908","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}

{"title":"Microwave Radiation Effects on the Acidic Properties of Fe/ZSM-5 Catalysts for Methanol Conversion","authors":"T. S. Ntelane, Themba E. Tshabalala, C. M. Masuku, M. Scurrell","doi":"10.2174/2213335608666210212103541","DOIUrl":"https://doi.org/10.2174/2213335608666210212103541","url":null,"abstract":"\u0000\u0000To use the microwave radiation as the post-treatment method to tune the acidic\u0000properties of Fe/ZSM-5 catalyst.\u0000\u0000\u0000\u0000ZSM-5 zeolite is a widely used standard catalyst in the methanol conversion to\u0000olefins and high-octane gasoline range hydrocarbons. However, the coke deposition and the concentration\u0000of acid sites determine its overall catalytic activity. Thus, the concentration of acid sites\u0000more precisely, the number of Brønsted acid sites, is vital in determining the activity of ZSM-5 zeolite\u0000and product distribution in the methanol-to-hydrocarbons reaction.\u0000\u0000\u0000\u0000(1) To modify ZSM-5 using an iron solution to form Fe/ZSM-5 via the impregnation\u0000method.\u0000\u0000(2) To tune the acidic properties of Fe/ZSM-5 using microwave radiation.\u0000\u0000(3) To check and determine the concentration of acidic sites using n-propylamine temperature-programmed\u0000surface reaction.\u0000\u0000(4) To check the effect of microwave radiation and acidic properties in the methanol conversion\u0000(product distribution) via methanol temperature-programmed surface reaction.\u0000\u0000\u0000\u0000Two sets of zeolites were used, with iron being introduced by ion-exchange from ferric\u0000nitrate (Fe(NO3)3 9H2O, Sigma Aldrich, ≥ 98% metal) solutions. These two series were designated\u0000as Z (0.5FeZ10/0-700) and X (0.5FeX10/0-700) after microwave treatment. The Z and X series possess the\u0000Si/Al framework ratio of 30 and 80, respectively. The TPSR studies were then conducted for characterization\u0000and catalytic tests.\u0000\u0000\u0000\u0000From the C3H9N-TPSR experiments, it was found that the concentration of Brønsted acid\u0000sites decreased with increasing microwave power level. Both X and Z series exhibited high selectivity\u0000to propene than ethene. Microwave treated catalysts (0.5FeZ10/280 and 0.5FeX10/462) with decreased\u0000concentration of Brønsted acid sites showed the highest propene/ethene ratios of 1.67 and\u00005.27, respectively.\u0000\u0000\u0000\u0000From the results obtained, it was found that the amount of methane evolved (as a measure\u0000of coke deposited) and the concentration of Brønsted acid sites decreased with increasing microwave\u0000power level (0-700 Watts). High selectivity to propene was found when using both X series\u0000(0.5FeX10/0-700) and Z series (0.5FeZ10/0-700) as catalysts. After decreasing the concentration of\u0000Brønsted acid using microwave treatment, the highest P/E ratios were observed for 0.5FeX10/280,\u00000.5FeX10/462, 0.5FeZ10/280 and 0.5FeZ10/462 catalysts.\u0000\u0000\u0000\u0000It is reasonable to suggest that microwave radiation could be a feasible post-synthesis modification\u0000step to produce ZSM-5 based catalysts that exhibit reduced concentration of Brønsted acid sites, reduced\u0000methane formation, increased catalytic activity and selectivity.\u0000","PeriodicalId":43539,"journal":{"name":"Current Microwave Chemistry","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47198010","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}

{"title":"Microwave-Assisted Synthesis of 3,4-Dihydropyrimidin-2(1H)-Ones Using Acid-Functionalized Mesoporous Polymer","authors":"Bishwajit Changmai, K. Rajkumari, D. Das, Lalthazuala Rokhum","doi":"10.2174/2213335608666210329130736","DOIUrl":"https://doi.org/10.2174/2213335608666210329130736","url":null,"abstract":"Synthesis and application of acid-functionalized mesoporous polymer catalyst for the synthesis of\u00003,4-Dihydropyrimidin-2(1H)-ones via Biginelli condensation reaction under microwave\u0000irradiation is investigated. Several analytical techniques such as FT-IR, BET, TEM, SEM and EDX\u0000were employed to characterize the synthesized polymeric catalyst. High acidity (1.15 mmol g-1\u0000),\u0000high surface area (90.44 m2\u0000g\u0000-1\u0000) and mesoporous nature of the catalyst effectively promoted the\u0000synthesis of 3,4-Dihydropyrimidin-2(1H)-ones. Microwave irradiation shows higher yield (89-98\u0000%) as compared to conventional heating (15-25 % yield) under our optimized reaction conditions\u0000such as 1:1:1.2 molar ratio of aldehyde/ethylacetoacetate/urea, catalyst loading of 6 wt.% (with\u0000respect to aldehyde), the temperature of 80 °C and microwave power of 50 W. The synthesized\u0000Biginelli products were fully characterized by 1H and 13C NMR. The reusability of the catalyst\u0000was investigated up to 5 successive cycles and it showed great stability towards the synthesis of\u00003,4-Dihydropyrimidin-2(1H)-ones without any significant depreciation in yields.","PeriodicalId":43539,"journal":{"name":"Current Microwave Chemistry","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45219211","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}

{"title":"Microwave-assisted Claisen Rearrangement of 1-Allyloxy-4-hydroxybenzene in the Presence of Metal Salt","authors":"Fumiyoshi Ozaki, Y. Okada","doi":"10.2174/2213335607666210106094449","DOIUrl":"https://doi.org/10.2174/2213335607666210106094449","url":null,"abstract":"\u0000\u0000Microwave-assisted Claisen rearrangement of allyloxybenzene with a hydroxyl group\u0000was conducted in the presence of metal salts. The rearrangement was promoted in the presence of\u0000an alkali metal salt, because the reaction substrate was converted into a phenoxide-type ion, which\u0000can efficiently absorb microwaves. In contrast, a Lewis acid was strongly coordinated to the ethereal\u0000oxygen, and this structure could also absorb microwaves efficiently.\u0000","PeriodicalId":43539,"journal":{"name":"Current Microwave Chemistry","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48616658","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}