ChemInform Abstract: Microwave-Assisted Organic Synthesis: General Considerations and Transformations of Heterocyclic Compounds

ChemInform ◽  
2010 ◽  
Vol 41 (35) ◽  
pp. no-no
Author(s):  
Kristof Kranjc ◽  
Marijan Kocevar
2009 ◽  
Vol 62 (3) ◽  
pp. 208 ◽  
Author(s):  
Mohammed Abid ◽  
Béla Török ◽  
Xudong Huang

Over the years, microwave-assisted organic synthesis (MAOS) became a commonly applied mainstream tool for the synthesis of heterocyclic compounds. The broad range of emerging applications in this field is mainly due to the significant contribution of MAOS to the development of ecofriendly processes. Various transformations have been developed for the synthesis of N-heterocycles under microwave conditions, including fast and selective processes. Tandem reactions involving greener reaction media, solvent-free conditions, and solid-phase synthesis are of exceptional interest in this area. In most transformations, microwave conditions dramatically enhanced reaction rates, as well as provided improved yields. This account highlights the most recent advancements in MAOS-based tandem processes for the synthesis of N-heterocycles.


2009 ◽  
Vol 62 (4) ◽  
pp. 392
Author(s):  
Mohammed Abid ◽  
Béla Török ◽  
Xudong Huang

Over the years, microwave-assisted organic synthesis (MAOS) became a commonly applied mainstream tool for the synthesis of heterocyclic compounds. The broad range of emerging applications in this field is mainly due to the significant contribution of MAOS to the development of ecofriendly processes. Various transformations have been developed for the synthesis of N-heterocycles under microwave conditions, including fast and selective processes. Tandem reactions involving greener reaction media, solvent-free conditions, and solid-phase synthesis are of exceptional interest in this area. In most transformations, microwave conditions dramatically enhanced reaction rates, as well as provided improved yields. This account highlights the most recent advancements in MAOS-based tandem processes for the synthesis of N-heterocycles.


Molecules ◽  
2021 ◽  
Vol 26 (20) ◽  
pp. 6293
Author(s):  
Hélio M. T. Albuquerque ◽  
Diana C. G. A. Pinto ◽  
Artur M. S. Silva

Microwave irradiation has become a popular heating technique in organic synthesis, mainly due to its short reaction times, solventless reactions, and, sometimes, higher yields. Additionally, microwave irradiation lowers energy consumption and, consequently, is ideal for optimization processes. Moreover, there is evidence that microwave irradiation can improve the regioselectivity and stereoselectivity aspects of vital importance in synthesizing bioactive compounds. These crucial features of microwave irradiation contribute to its inclusion in green chemistry procedures. Since 2003, the use of microwave-assisted organic synthesis has become common in our laboratory, making our group one of the first Portuguese research groups to implement this heating source in organic synthesis. Our achievements in the transformation of heterocyclic compounds, such as (E/Z)-3-styryl-4H-chromen-4-ones, (E)-3-(2-hydroxyphenyl)-4-styryl-1H-pyrazole, (E)-2-(4-arylbut-1-en-3-yn-1-yl)-4H-chromen-4-ones, or (E)-2-[2-(5-aryl-2-methyl-2H-1,2,3-triazol-4-yl)vinyl]-4H-chromen-4-ones, will be discussed in this review, highlighting the benefits of microwave irradiation use in organic synthesis.


2019 ◽  
Vol 23 (11) ◽  
pp. 1214-1238 ◽  
Author(s):  
Navjeet Kaur ◽  
Pranshu Bhardwaj ◽  
Meenu Devi ◽  
Yamini Verma ◽  
Neha Ahlawat ◽  
...  

Due to special properties of ILs (Ionic Liquids) like their wide liquid range, good solvating ability, negligible vapour pressure, non-inflammability, environment friendly medium, high thermal stability, easy recycling and rate promoters etc. they are used in organic synthesis. The investigation for the replacement of organic solvents in organic synthesis is a growing area of interest due to increasing environmental issues. Therefore, ionic liquids have attracted the attention of chemists and act as a catalyst and reaction medium in organic reaction with high activity. There is no doubt that ionic liquids have become a major subject of study for modern chemistry. In comparison to traditional processes the use of ionic liquids resulted in improved, complimentary or alternative selectivities in organic synthesis. The present manuscript reported the synthesis of multiple nitrogen containing five-membered heterocyclic compounds using ionic liquids. This review covered interesting discoveries in the past few years.


2013 ◽  
Vol 17 (5) ◽  
pp. 474-490 ◽  
Author(s):  
Amit Kumar Gupta ◽  
Neetu Singh ◽  
Krishna Nand Singh

2019 ◽  
Vol 16 (6) ◽  
pp. 527-543 ◽  
Author(s):  
Pedro M.E. Mancini ◽  
Carla M. Ormachea ◽  
María N. Kneeteman

During the last twenty years, our research group has been working with aromatic nitrosubstituted compounds acting as electrophiles in Polar Diels-Alder (P-DA) reactions with different dienes of diverse nucleophilicity. In this type of reaction, after the cycloaddition reaction, the nitrated compounds obtained as the [4+2] cycloadducts suffer cis-extrusion with the loss of nitrous acid and a subsequent aromatization. In this form, the reaction results are irreversible. On the other hand, the microwave-assisted controlled heating become a powerful tool in organic synthesis as it makes the reaction mixture undergo heating by a combination of thermal effects, dipolar polarization and ionic conduction. As the Diels-Alder (D-A) reaction is one of the most important process in organic synthesis, the microwave (MW) irradiation was applied instead of conventional heating, and this resulted in better yields and shorter reaction times. Several substituted heterocyclic compounds were used as electrophiles and different dienes as nucleophiles. Two experimental situations are involved: one in the presence of Protic Ionic Liquids (PILs) as solvent and the other under solvent-free conditions. The analysis is based on experimental data and theoretical calculations.


2020 ◽  
Vol 3 (1) ◽  
pp. 57
Author(s):  
Luka Barešić ◽  
Davor Margetić ◽  
Zoran Glasovac

The cycloaddition strategy was employed in order to obtain a 7-oxanorbornene framework substituted with a guanidine moiety or its precursor functional groups: protected amine or thiourea. In order to optimize the conditions for the cycloaddition, several environmentally-friendly methods—microwave assisted organic synthesis, high pressure synthesis, high speed vibrational milling, and ultrasound assisted synthesis—were employed. The outcomes of the cycloaddition reactions were interpreted in terms of endo/exo selectivity, the conversion of the reactants to the product, and the isolated yields. In general, our results indicated the HP and HSVM approaches as the methods of choice to give good yields and conversions.


ChemInform ◽  
2010 ◽  
Vol 33 (8) ◽  
pp. no-no
Author(s):  
Pelle Lidstroem ◽  
Jason Tierney ◽  
Bernard Wathey ◽  
Jacob Westman

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