On June 30, 2021, Taib, Layla Ahmed; Keshavarz, Mosadegh; Parhami, Abolfath published an article.COA of Formula: C6H8O3 The title of the article was Solvent-free synthesis of 4-substituted coumarins catalyzed by novel Bronsted acidic ionic liquids with perchlorate anion: a convenient and practical complementary method for pechmann condensation. And the article contained the following:
Herein, three novel sulfonic-functionalized Bronsted acidic ionic liquids containing perchlorate anion counterparts e.g., I were prepared These ionic liquid catalysts e.g., I were prepared through simple and ecofriendly procedures and then applied as efficient catalysts with high yields under solvent-free conditions for the synthesis of 4-substituted coumarins e.g., II through the Pechmann condensation of different phenols e.g., naphthalen-1-ol and β-ketoesters R(O)CH(R1)C(O)OR2 [R = Me, Ph; R1 = H; R2 = Et; R1R2 = -(CH2)2-]. Compared to previous works, the proposed method offers several benefits, such as cleaner reactions, decreased reaction times, high yields, and the lack of laborious workup or purification procedures. Particularly, these catalysts make the condensation of less activated phenols feasible. Besides the described benefits, this advanced protocol was applied successfully for the synthesis of coumarins e.g., III from γ-lactone as 3-acetyldihydrofuran-2(3H)-one. The simplicity in operation, applicability and feasibility of this protocol for diverse substrates make it an efficient alternative to conventional methods. The experimental process involved the reaction of 3-Acetyldihydrofuran-2(3H)-one(cas: 517-23-7).COA of Formula: C6H8O3
The Article related to coumarin preparation green chem, phenol ketoester pechmann condensation ionic liquid perchlorate anion catalyst, Heterocyclic Compounds (One Hetero Atom): Benzopyrans (Including Coumarins, Isocoumarins, Chromones, Benzopyrones, Dibenzopyrans, and Other Arenopyrans) and other aspects.COA of Formula: C6H8O3
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