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artemisinin
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Optimization and Continuous Synthesis of Artemisinin Using Core-Shell Nano-Catalysts by Means of Micro-Rector
, Ph.D. Dissertation Sharif University of Technology ; Kazemeini, Mohammad (Supervisor)
Abstract
Artemisinin as a natural peroxide possess a high anti parasite, and antivirus (Covid-19) properties which could be synthesized through the photooxygenation of dihydroartemisinic acid. This production possesses a lot of difficulties, for example, homogeneous catalyst is used for the photooxygenation reaction which makes photocatalyst and solvent non-reusable. In addition, separation of products from solvent and photocatalysts is difficult. Photooxygenation needs high pressure and low temperature which is very costly. Besides, because of several by-products which are producing during photooxygenation and protonation reactions, Artemisinin yield decreases. The aim of this study is to optimize...
Selective photooxygenation of dihydroartemisinic acid in a reusable microreactor with physically immobilized photocatalysts
, Article Materials Research Bulletin ; Volume 145 , 2022 ; 00255408 (ISSN) ; Kazemeini, M ; Tyagi, A ; Roxas, A. P ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Photocatalytic production of organic materials including Artemisinin has been hampered in the pharmaceutical industry because of low reusability and selectivity of photocatalysts. In this work, reusable photocatalysts were synthesized through novel physical and electrostatic immobilizations. After four reaction cycles of dihydroartemisinic acid (DHAA) photooxygenation using physically supported photosensitizers, the conversion was slightly reduced from 81 to 78%, indicating their high reusability. This occurred while maintaining the selectivity of the desired product above 85%, which was higher than that of the homogeneous photosensitizers. Then, a continuous-flow microreactor functionalized...