Bio-based sustainable heterogeneous catalyst for ipso-hydroxylation of arylboronic acid

Green Synthesis of Novel Triazolothiadiazine‐Coumarins Catalyzed by Agro Waste Extract: An Approach towards In‐Silico and In‐Vitro Anti‐Fungal Activity

“…By collecting lemon peels from local lemon juice fruit stall, the catalyst WELPSA (Figure 4) was developed. The peel was cleansed with distilled water, shade‐dried and burnt to obtain lemon peel ash (LPA), the ash was then drenched in distilled water for about 2 hrs and the resultant extract was filtered and collected as WELPSA [29–33] . The p H of the lemon peel ash (LPA) extract was found to be around 12.00–12.02 and this intensely basic nature is one among the significant factors in the condensation and cyclization of the reactants to yield final compounds.…”

“…The peel was cleansed with distilled water, shade-dried and burnt to obtain lemon peel ash (LPA), the ash was then drenched in distilled water for about 2 hrs and the resultant extract was filtered and collected as WELPSA. [29][30][31][32][33] The pH of the lemon peel ash (LPA) extract was found to be around 12.00-12.02 and this intensely basic nature is one among the significant factors in the condensation and cyclization of the reactants to yield final compounds. Using this, the compounds were synthesized and purified by recrystallization in ethanol.…”

Surface Nanoarchitectonics of Boron Nitride Nanosheets for Highly Efficient and Sustainableipso-Hydroxylation of Arylboronic Acids

“…The direct hydroxylation of aromatic compounds to its corresponding phenols is a challenging task in synthetic organic chemistry. Phenols constitute an important class of biologically active compounds owing to their antibacterial, antihyperglycemic, antitumor, antiviral, antitumor, antimutagenicity, pro-oxidant, and cardioprotective properties. , Phenols and their derivatives are commonly used in industries and companies for the synthesis of fine chemicals, pharmaceuticals, and agrochemicals. , Phenolic motifs are also present in various natural products, such as terpenoids, macrolides, quinines, alkaloids, and aryl steroids. , Due to their prevalent importance, dedicated efforts have been put forward to ease the synthesis of phenols. To date, different approaches have been utilized for the synthesis of phenolic compounds like nucleophilic substitution of aryl halides by hydroxyl group, C–H aryl ring oxidation and hydrolysis of diazonium salts, hydroxylation of aryl halides using hydroxide salts, hydroxylation of aryl halides, and so on. − However, the use of toxic solvents, homogeneous catalysts, harsh reaction conditions, and expensive metal-based catalysts, tedious reaction workups, and longer reaction time made these processes undesirable for large scale applications. , …”

Template-Less and Surfactant-Less Synthesis of CeO2 Nanostructures for Catalytic Application in Ipso-hydroxylation of Aryl Boronic Acids and the aza-Michael Reaction

“…For example, many reports are available in recent years where more than 1.5 equivalents of H 2 O 2 was used as an oxidizing agent while carrying out the ipso -hydroxylation of aryl boronic acid. 30 , 37 , 42 , 43 Moreover, reports are also available on the ipso -hydroxylation of aryl boronic acids without the use of any oxidizing agent. 38 , 44 However, those protocols require prolonged reaction times and high temperatures, yet the yield of the product is low, which is another disadvantage for commercial use.…”

“…In most of the reported protocols involving H 2 O 2 as the oxidant, it has been observed that while trying to make a green catalytic system, they often underestimate the “atom economy” principle of green chemistry. For example, many reports are available in recent years where more than 1.5 equivalents of H 2 O 2 was used as an oxidizing agent while carrying out the ipso -hydroxylation of aryl boronic acid. ,,, Moreover, reports are also available on the ipso -hydroxylation of aryl boronic acids without the use of any oxidizing agent. , However, those protocols require prolonged reaction times and high temperatures, yet the yield of the product is low, which is another disadvantage for commercial use. , Herein, we report the development of a catalyst system for ipso -hydroxylation of boronic acids associated with a high atom economy using CeO 2 nanostructures as reusable catalysts.…”