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Furanic di‐carboxylate derivatives of 5‐Hydroxymethylfurfural (HMF) are nowadays important in the polymer industry as they are used as building blocks for bio‐based polyesters. The high reactivity of HMF compels to avoid harsh synthetic conditions. Therefore, developing mild catalytic processes for its selective oxidation is a challenging task. Herein, we report the first oxidative esterification of HMF to dimethyl furan‐2,5‐dicarboxylate (FDCM) under flow conditions using oxygen as oxidant. For that purpose, a new series of nitrogen‐doped carbon‐supported bimetallic Co/Ru heterogeneous catalysts were prepared and characterized by XRD, XPS and N2 physisorption. These analyses revealed that the porosity of the materials and order of impregnation of the metals to the carbon supports lead to varying catalytic activities. Under optimized conditions the flow reactor showed a 15‐fold increase on the production of FDCM compared to batch conditions. [ABSTRACT FROM AUTHOR]

In a one-step procedure, various β-bromoalcohols were synthesized from natural terpenes in good to excellent yields. Using different catalysts, the reaction was carried out at room temperature, with H2O as nucleophile and N-bromosuccinimide as a bromine source under mild reaction conditions. The synthesized β-bromoalcohols were subsequently converted in situ to the corresponding epoxides in good yields. [ABSTRACT FROM AUTHOR]

The radical alkylation of cyclododecanone (CDD) with allyl acetate (AlAc) yielding 2‐[3‐(acetyloxy)propyl] cyclododecanone (CDDPA) in the presence of different inorganic radical initiators was investigated. The most useful initiator among other inorganic metal oxides was found to be CuO. The molar ratio of CDD and AlAc was varied between 10:1 and 3:1. CuO was characterized by using different analytical methods, such as N2 adsorption, powder X‐ray diffraction, temperature‐programmed reduction, scanning electron microscopy, and X‐ray photoelectron spectroscopy. The reaction was performed in a batch system, by adding all the reactants at once, and in a semibatch procedure by dosing AlAc over the whole time of the experiment. Different parameters that affected the selectivity of CDDPA were studied, such as the ratio of CDD/AlAc, reaction time, surface of CuO initiator, and reaction temperature. The best result was obtained with 21 % conversion of CDD and 77 % selectivity to CDDPA at a final molar ratio of CDD/AlAc = 4:1 in the semibatch procedure. [ABSTRACT FROM AUTHOR]

Highlights from the article: Cover Feature: Heterogeneously Catalysed Oxidative Dehydrogenation of Menthol in a Fixed-Bed Reactor in the Gas Phase (ChemistryOpen 8/2019) Keywords: oxidative dehydrogenation; gas-phase reactions; supported silver catalyst; supported copper catalyst; supported ruthenium catalyst Oxidative dehydrogenation, gas-phase reactions, supported silver catalyst, supported copper catalyst, supported ruthenium catalyst.