Amphiphilic silica is synthesized with the simultaneous introduction of two kinds of polar and weakly polar organic groups on its surface using a one-step reverse-phase microemulsion method. The obtained materials present as nanospheres with a size of ≈100 nm. A high percentage (≈80%) of silicon species can be exposed and the amount of surface SiOH increased by above 50% with the introduction of organic groups. Plenty of groups, including polar groups (3-aminopropyl and hydroxyl) and weakly polar group (n-propyl) coexisting on the surface, enable the material to show amphiphilicity. This amphiphilic material can show an excellent property for the removal of various organic dyes from the aqueous solution, and the maximum adsorption capacity of Congo Red,

Selective oxidation of hydrocarbons with molecular oxygen at ambient temperature is full of challenge, and efficient activation of the inert C−H bond under mild conditions is the breakthrough point. Due to the promotion effect of the organic solvent hexafluoroisopropanol (HFIP) and α-Fe 2 O 3 , highly reactive phthalimide-N-oxyl radical (PINO) species were produced under the photoirradiation of blue light (455 nm, 3 W) without additional heating, which were utilized to activate various aromatic hydrocarbons. Combining with the hyperoxide decomposition catalysis, the excellent conversion (98%) and the total selectivity (99%) to the ketone (aldehyde) and alcohol were successfully obtained at the ambient temperature of 30 °C. It was found that the reactivity and lifetime of PINO was closely related with the adsorption attitude of PINO on the surface of α-Fe 2 O 3 , which could be modulated to be most beneficial for the catalytic efficiency by relying on the homogeneous interaction between PINO and HFIP and the heterogeneous interaction between PINO and the surface of α-Fe 2 O 3 .

A series of N-alkyl pyridinium salts were synthesized and employed as metal-free catalyst for the selective oxidation of methyl aromatic hydrocarbon with molecular oxygen.

BACKGROUND Aromatic thioether derivatives exist widely in natural products and have significant applications in modern synthesis and the pharmaceutical industry; for example, 2‐sulfanylphenols and arylthioquinones are important intermediates in the processing of anticancer, antibiotic, antivirus and antimalarial drugs. Direct C─H hydroxylation was considered as one of the efficient methods for the synthesis of these compounds. Homogeneous transition metal catalysts usually were used through a cross‐coupling of halogen‐substituted phenols with thiophenols. However, from the perspectives of sustainable development and easy recovery, it is necessary to develop an efficient and recoverable catalytic system to realize the synthesis of aromatic thioether derivatives with good efficiency and recyclability. RESULTS The heterogeneous catalyst [Cu(binap)I]2@HT in the present work showed good catalytic activity for the C─H hydroxylation of benzenethiol and phenylboronic acid. The catalytic system was tolerant to various substituents including alkyl, alkoxy, ester, halogen or trifluoromethyl on the phenyl ring of the thiophenols or arylboric acids. In addition to electron‐donating groups, the products with strong electron‐withdrawing groups, such as methyl formylate and trifluoromethyl also were achieved with good yields at 90 °C for 12 h (68% and 66%, respectively). Repeated experiment results showed that the catalyst could be reused at least five times without obvious decrease in catalytic activity. CONCLUSION A BINAP‐Cu complex supported on hydrotalcite was prepared and used as a heterogeneous catalyst for the C─H activation of thiophenol under mild reaction conditions. Through a cascade C─H hydroxylation and further oxidation process, 2‐Sulfanylphenols and arylthioquinones could be obtained with moderate‐to‐good yields for a series of 2‐(phenylthio)phenol derivatives using the heterogeneous catalyst [Cu(binap)I]2@HT. In addition, this heterogeneous catalyst showed good recylbility. © 2020 Society of Chemical Industry

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