Synergistic effect of PEG-coated ZnO nanoparticles and ultrasonic irradiation on the C–B bond cleavage of aryl boronic acids

Surfactant-free synthesis of Ag@TiO2 and CuO@TiO2 photocatalyst: a comparative study of their photocatalytic activity for reduction of nitroaromatics in water

“…The blue emission peak at 467 nm is indicative of the presence of oxygen vacancies in TiO 2 nanoparticles. The emission peaks observed at 480 nm and 492 nm might be due to the electronic transition between ionized oxygen vacancies and interstitial oxygen or surface defects [44,[53][54][55]. As observed from figure 7, the intensity of all the peaks decreases for Ag@TiO 2 and CuO@TiO 2 compared to pure TiO 2, and CuO-loaded TiO 2 showed the lowest PL intensity.…”

Ultrasonic irradiation-assisted MnFe2O4 nanoparticles catalyzed solvent-free selective oxidation of benzyl alcohol to benzaldehyde at room temperature

“…50 Further, our research group has also reported recently the use of ultrasonic irradiation to carry out aza-Michael reaction and C-B bond cleavage reactions very effectively in a milder way. 51,52 To check if the activity of these catalysts under consideration can be enhanced under ultrasonic irradiation, we repeated the catalytic reaction under ultrasonic irradiation keeping other reaction parameters identical. Surprisingly, we noticed that the yield of the products increased signicantly with all three catalysts under ultrasonic irradiation (Table 3; entries 5-7).…”

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

“…However, most of the traditional synthesis procedures have less substrate scope in terms of yield and require very harsh conditions, such as the requirement of strong bases, high temperature and pressure, and so forth . To overcome those demerits, the ipso -hydroxylation of aryl boronic acids has been adopted in recent times to synthesize phenols due to its various advantages such as the ease of conversion of aryl boronic acids into phenols, nontoxicity, and stability of aryl boronic acids against moisture. , Accordingly, different catalyst systems such as poly­( N -vinylpyrrolidone)-H 2 O 2 and poly­(4-vinyl pyridine)-H 2 O 2 complexes, N -oxide, hypervalent iodine (III), supported Ag nanoparticles (NPs), , graphene oxide, Cu 2 O NPs, ZnO NPs, , and Fe 2 O 3 /Al 2 O 3 nanocomposites have been reported recently by several research groups across the world for the oxidative hydroxylation of aryl boronic acid. 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.…”