95-56-7Relevant articles and documents
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Merck
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Imidazolium-urea low transition temperature mixtures for the UHP-promoted oxidation of boron compounds
Martos, Mario,Pastor, Isidro M.
, (2022/01/03)
Different carboxy-functionalized imidazolium salts have been considered as components of low transition temperature mixtures (LTTMs) in combination with urea. Among them, a novel LTTM based on 1-(methoxycarbonyl)methyl-3-methylimidazolium chloride and urea has been prepared and characterized by differential scanning calorimetry throughout its entire composition range. This LTTM has been employed for the oxidation of boron reagents using urea-hydrogen peroxide adduct (UHP) as the oxidizer, thus avoiding the use of aqueous H2O2, which is dangerous to handle. This metal-free protocol affords the corresponding alcohols in good to quantitative yields in up to 5 mmol scale without the need of further purification. The broad composition range of the LTTM allows for the reaction to be carried out up to three consecutive times with a single imidazolium salt loading offering remarkable sustainability with an E-factor of 7.9, which can be reduced to 3.2 by the threefold reuse of the system.
Cu2O/TiO2 as a sustainable and recyclable photocatalyst for gram-scale synthesis of phenols in water
Hosseini-Sarvari, Mona,Keshavarz, Kimia,Tavakolian, Mina
, (2021/08/30)
A green and straightforward protocol was developed for the synthesis of phenols from aryl boronic acid using an inexpensive and available Cu2O/TiO2 photocatalyst under visible light and sunlight. This approach proceeded in mild reaction conditions in water and the presence of air as a green oxidant, resulting in the corresponding phenols in good to excellent yields. Sunlight was also a sustainable source for this photochemical reaction. Heterogeneous nano photocatalyst was successfully recovered in 8 consecutive runs. It is noteworthy that, the photocatalyst exhibited high activity for the large-scale synthesis of phenols.
Electrophotocatalytic C?H Heterofunctionalization of Arenes
Huang, He,Lambert, Tristan H.
supporting information, p. 11163 - 11167 (2021/04/19)
The electrophotocatalytic heterofunctionalization of arenes is described. Using 2,3-dichloro-5,6-dicyanoquinone (DDQ) under a mild electrochemical potential with visible-light irradiation, arenes undergo oxidant-free hydroxylation, alkoxylation, and amination with high chemoselectivity. In addition to batch reactions, an electrophotocatalytic recirculating flow process is demonstrated, enabling the conversion of benzene to phenol on a gram scale.