Current Organic Chemistry - Volume 22, Issue 5, 2018

Background: Aminopyrimidines represent very important class of functionalized heterocycles having wide applications in organic and medicinal chemistry. Recently, considerable attention has been paid on exploration of aminopyrimidines in pot, atom and step economic multicomponent reactions. Objective: The main objective of this review is to give an overview on the recent applications of aminopyrimidines in multicomponent reactions. Method: In this review, we have broadly divided all the aminopyrimidine based multicomponent reactions into two major categories leading to (i) cyclic pyrimidine fused derivatives and (ii) acyclic substituted pyrimidine derivatives as products. Again reactions forming fused heterocycles from the aminopyrimidine based multicomponent reactions have been sub categorized as MCRs providing five membered, six membered and spirofused products. Similarly, MCRs providing acyclic substituted products have been subdivided into two categories involving only C-nucleophilic site of the aminopyrimidine to give C-substituted aminopyrimidines and using N-nucleophilic site to provide N-substituted acyclic products. Conclusion: We have shown the various reactivity patterns of aminopyrimidines in multicomponent reactions and up-to-date literature on aminopyrimidine based MCRs has been systematically presented. Finally, aminopyrimidines are considered as promising substrates in MCRs for the synthesis of diverse heterocycles. We hope that this review will serve as a stimulus for ongoing research in the field of MCRs and heterocyclic chemistry.

Background: Carbon-based structural materials are widely studied in the field of renewable energy and environmental sciences. Utilization of abundant, natural, renewable energy precursors together with simple and low energy processes can contribute to reduced emissions of greenhouse gas so is considered as fundamental for manufacturing of sustainable nanostructured materials. Description: Among different resources available for the generation of nanostructured materials, plant biomass is superior in terms of economic, environmental and social issues. In addition, transformation of low-value biomass to emerging renewable materials is advantageous compared to dumping and incinerating the biomass. There are a number of techniques and processes for the production of nanostructured materials from biomass. Pyrolysis and hydrothermal carbonization (HTC) may be used to convert biomass into nanostructured materials. Objective: This study reviews and compares the production of nanostructured materials from pyrolysis and HTC. Furthermore, the latest developments in pyrolysis and HTC for nanomaterials production are assessed and comparative characteristics are studied for nanomaterials obtained.

Background: Condensation reactions have attracted increasing attentions due to their important organic transformations in a wide variety of fields of organic chemistry. The main limitations of conventional methods are urgently needed for the development of efficient and heterogeneous catalytic systems. Objective and Method: Supported ionic liquids have broad applications in catalytic reactions due to their significant properties such as wide range of temperature, excellent thermal stability, negligible volatility, high ionic conductivity, and high surface area with a remarkable level of catalytic performance. Moreover, due to their heterogeneous properties, they have the attractive features of easy separation and recyclability. In this review, we highlight the critical role of supported ILs as green heterogeneous catalysts in catalytic condensation reactions such as Aldol condensation reaction, Biginelli reaction, Knoevenagel condensation and other condensation reactions. Results: Different supported ILs having highly promising future prospects in the field of condensation reactions have been investigated. Their applications in condensation reactions possess attractive features such as high efficiency, easy separation from the reaction mixture and excellent recyclability. Conclusion: The versatilities and adaptabilities of supported ILs in various condensation reactions are considered as a powerful research field in these transformations. It should be certain that this kind of supported IL materials will play an important role in condensation reactions and other organic reactions in the near future.

Phthalocyanine, a large ring complex with 18 π electrons, is derived from the abundant porphyrin in nature. In recent years, the phthalocyanine based materials have aroused great interest of scientists, due to their special skeleton structure, which could be screened and assembled by introducing central ions, axial ligands and substituted groups, and thus obtained materials with special physical and chemical stabilities, as well as photochemical, electrochemical, photocatalytic and other functions. In this review, recent advances of phthalocyanine compounds in the field of photochemistry and electrochemistry have been reviewed and summarized. Firstly, progress in photochemical properties was introduced, including research and ideas of optical limiting properties, photocatalysis and photodynamic therapy. The existing problems and future research directions of phthalocyanine compounds based on photochemical applications are summarized and analyzed. Secondly, the phthalocyanine compounds as electrode materials for lithium ion batteries were introduced. The modification idea, energy storage mechanism, the existing problems and future research directions of phthalocyanine compounds as energy storage materials are summarized and analyzed. The structural diversity and adjustable properties of phthalocyanine based material make it special optical, electrical and magnetic material, which can provide theoretical guidance for the design of large ring conjugated photoelectric functional materials with excellent performance.

Background: We report a novel MCR4 useful for generating chiral analogs of staurosporine a promiscuous and potent protein kinases inhibitor. Method: Our strategy introduces the use of substituted tetramic acids as chiral precursors which together with an aldehyde, an isocyanide, a dienophile and a Lewis acid lead to hexa-substituted benzenes in one pot. Conclusion: Interestingly, the use of chiral precursors not only allowed obtaining a stereo- controlled reaction, but also observing unusual atropo-diastereomers with axial chirality. The reaction can be carried out both under thermal or microwave conditions. The methodology is demonstrated for a panel of aldehydes, tetramic acids, isocyanides and dienophiles.