Hexavalent Se? Yes! Selenium on polymers exhibits quite different properties compared to that in small molecules. Hexavalent Se, rare in organoselenium chemistry, was found to be the major species on polymers. The high-valent Se species on recyclable polymer resins could quickly catalyze the oxidation reaction of cyclohexene with H2O2 in water to produce industrially important intermediate trans-1,2-cyclohexanediol in almost quantitative yield. In the catalytic cycle, high valent Se species were reduced to divalent Se, a highly activated species that could be re-oxidized by air so that no excess H2O2 was required for the reaction. The results were superior to those of reactions catalyzed by small molecules, for which excess H2O2, long reaction time or expensive CF3-activated catalysts and environmentally unfriendly MeCN solvent were required.

Design and preparation of a polymer resin-supported organoselenium catalyst with industrial potential

Gram-Scale Preparation of Pd@PANI: A Practical Catalyst Reagent for Copper-Free and Ligand-Free Sonogashira Couplings

Organoselenium-catalyzed selectivity-switchable oxidation of β-ionone

Energy saving and environment-friendly element-transfer reactions with industrial application potential

Recyclable (PhSe)2-catalyzed selective oxidation of isatin by H2O2: a practical and waste-free access to isatoic anhydride under mild and neutral conditions

The synthesis of phosphine-based functional covalent organic frameworks (COFs) has attracted great attention recently. Herein, we present two examples of triphenylphosphine-based COFs (termed P-COFs) with well-defined crystalline structures, high specific surface areas, and good thermal stability. Furthermore, rhodium catalysts with these P-COFs as support material show high turnover frequency for the hydroformylation of olefins, as well as excellent recycling performance. This work not only extends the phosphine-based COF family, but also demonstrates their application in immobilizing homogeneous metal-based (e.g., Rh-phosphine) catalysts for application in heterogeneous catalysis.

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Triphenylphosphine-Based Covalent Organic Frameworks and Heterogeneous Rh-P-COFs Catalysts

To solve serious energy and environmental crises caused by rapid industrial development, the formation of heterostructured photocatalysts is a promising approach for efficient and scalable H2 produ...

2D–2D Heterojunctions of a Covalent Triazine Framework with a Triphenylphosphine-Based Covalent Organic Framework for Efficient Photocatalytic Hydrogen Evolution

Unexpectedly, L-proline/piperidine was found to be a better recyclable catalyst system than L-proline or piperidine alone in the condensation of acetone to prepare mesityl oxide (MO), an important intermediate in the chemical industry. Binding the catalyst system onto polymer resin enhanced the MO selectivity and reduced the catalyst loss. The mechanism of the bi-component catalyst system was also studied through control reactions, as well as by dynamic calculations. The MO selectivity could reach 74.4% and its isolated yield could reach 73.9%, based on the consumed acetone. Although the result does not immediately meet the requirement of industrial production, this study provides a novel organocatalyst system, which might offer a potential alternative to traditional inorganic catalysts that can be used under mild and neutral conditions.

Design and application of the recyclable poly(L-proline-co-piperidine) catalyst for the synthesis of mesityl oxide from acetone

The noble-metal-free Ni2P/CTF composites for efficient photocatalytic hydrogen evolution under visible-light irradiation

A novel homogeneous copolymer catalyst was synthesized via single step radical copolymerization and developed for the aldol reaction. It was demonstrated that the catalyst possessed excellent activity and stereoselectivity. The secondary structure of the copolymer catalyst was evaluated by circular dichroism. Furthermore, the catalyst was readily recovered without loss of conversion and stereoselectivity even after ten cycles.

Yubing Liu

Papers

Triphenylphosphine-Based Covalent Organic Frameworks and Heterogeneous Rh-P-COFs Catalysts

2D–2D Heterojunctions of a Covalent Triazine Framework with a Triphenylphosphine-Based Covalent Organic Framework for Efficient Photocatalytic Hydrogen Evolution

Design and application of the recyclable poly(L-proline-co-piperidine) catalyst for the synthesis of mesityl oxide from acetone

The noble-metal-free Ni2P/CTF composites for efficient photocatalytic hydrogen evolution under visible-light irradiation

A novel poly(N-isopropyl-acrylamine-co-l-proline) catalyst for aldol reaction: synthesis, catalytic performance and recyclability