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The incorporation of hydrophilic and basic sites from phosphotriazaadamantane and saccharine in a water‐soluble Pd complex and the subsequent confinement into mesoporous silica support increases the activity and stability of the palladium catalytic species for the room‐temperature aqueous hydrogenation of either bicarbonate or CO2 into formic acid. The use of low Pd loadings (<0.1 mmolPd g−1) of the well‐dispersed complex on SBA‐15 mesoporous silica allows performing the reaction under room temperature, and aqueous conditions, exhibiting TON of ca. 40–100, for the CO2 or bicarbonate hydrogenation, respectively, which is one order of magnitude higher than the homogeneous case, allowing the easy isolation and recycling of the solid catalyst. [ABSTRACT FROM AUTHOR]

Since 5-(hydroxymethyl)furfural (HMF) has been labelled as the "sleeping giant" of the bio-based platform-chemical realm, numerous investigations have been devoted to the exploitation of this versatile molecule and its endless chemical transformations into novel monomers for producing bio-based polymers. However, beyond 2,5-furandicarboxylic acid (2,5-FDCA), little attention has been devoted to key aspects that deserve being addressed before bringing forward other HMF-derivatives into the bio-based plastic market, i.e., procedures, scaling-up of the syntheses, products' purification, physical–thermal properties, and above all green metrics (sustainability/greenness of procedures). This critical review focuses on the most investigated derivatives of HMF beyond 2,5-FDCA, assessing their exploitation as monomers for bio-based polymers. HMF-derived compounds have been classified according to their functionalities, i.e., aldehyde-, diol-, polyol-, amine-, acid-, ester-, carbonate-, acrylate-, and epoxy-based monomers. The related synthetic approaches are discussed, evaluating the sustainability of the procedures reported so far, based on green metrics such as the environmental factor (E-factor) and the process mass intensity (PMI). For each family of HMF derivatives, their use as monomers for the synthesis of bio-based polymers has been addressed, taking into consideration the efficiency of the polymerisation reactions, the physical–chemical and thermal properties of the resulting bio-based polymers, as well as their biodegradability if applicable. The overall picture that emerges is that much has been achieved for the synthesis of furan monomers; however, many obstacles still need to be overcome prior to massively introducing these compounds into the bio-based plastic market. Hopefully, the data reported in this review will shed light on the goals achieved so far, and on some critical issues that must still be tackled in the short- or medium-term for a more sustainable and however efficient industrial process. [ABSTRACT FROM AUTHOR]

The art of tuning functional polymeric materials through the covalent incorporation of organocatalysts lies at the core of creating asymmetric immobilized chiral catalysts that mimic the enzymatic action. Herein, we explore diverse synthetic techniques to immobilize l‐proline‐derived N‐carbonyl amides on functional polymeric matrices, transforming them into chiral Lewis bases for facilitating the asymmetric reduction of ketimines with HSiCl3. A comprehensive examination of the design factors, encompassing linker selection, anions, and polymeric support characteristics, enables precise adjustment of steric and electronic features in these immobilized catalysts. This approach establishes structure‐performance relationships, ultimately enabling the development of an engineered immobilized organocatalytic system that meets the desired criteria for activity, stability, and selectivity. [ABSTRACT FROM AUTHOR]

The introduction of iron ionic sites by metal exchange of defective homometallic nickel pyrazolate frameworks generates non‐precious, Earth‐abundant, first‐row heterometallic Fe/Ni‐pyrazolate frameworks. The Fe incorporation at the Ni nodes of the framework allows to control the hydrogen peroxide activation, minimizing its decomposition and O2 liberation, occurring at the homometallic Ni nodes. The generation of Fe−OH reactive oxygen species at the heterometallic Fe/Ni nodes is demonstrated by the higher activity in the proof‐of‐concept oxidation of 1‐phenylethanol to acetophenone in an aqueous medium. [ABSTRACT FROM AUTHOR]