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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. �� 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

A series of heteroleptic copper photosensitizers [(P _ P)Cu(N _ N(SO3Na)2)] + containing sulfonate anchor groups is described. In the presence of titanium dioxide they form composites, which are active photosensitizers in the light driven reduction of protons. Further stabilization of these systems is achieved by encapsulation within a plasma-polymerized allylamine (PPAAm) layer. The resulting PPAAm-CuPS-TiO2-composites exhibit a strong absorption in the visible region of the light. Photocatalytic hydrogen production is performed by using only nonnoble metals. In the presence of an iron reduction catalyst a maximum turnover number of 2452 is obtained.