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Polyoxometalates (POMs) are ideal components for reversible multi-electron storage in energy technologies. To-date, most redox-applications employ only single, individual POM species, which limits the number of electrons that can be stored within a given potential window. Here, we report that spontaneous redox self-equilibration during cluster synthesis leads to the formation of two structurally related polyoxovanadates which subsequently aggregate into co-crystals. This results in systems with significantly increased redox reactivity. The mixed POM system was formed by non-aqueous self-assembly of a vanadate precursor in the presence of Mg 2+ , resulting in two mixed-valent (V IV/V ) species, [(MgOH)V 13 O 33 Cl] 4- (={MgV 13 }) and the di-vanadium-functionalized species [V 14 O 34 Cl] 4- (={V 14 }), which co-crystallize in a 1 : 1 molar stoichiometry. Experimental data indicate that in the native state, {MgV 13 } is reduced by three electrons, and {V 14 } is reduced by five electrons. Electrochemical studies in solution show, that the system can reversibly undergo up to fourteen redox transitions (tentatively assigned to twelve 1-electron processes and two 2-electron processes) in the potential range between -2.15 V to +1.35 V (vs Fc + /Fc). The study demonstrates how highly redox-active, well-defined molecular mixtures of mixed-valent molecular metal oxides can be accessed by redox-equilibration during synthesis, opening new avenues for molecular energy storage., (© 2024 The Author(s). Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Electrochemically generated hypervalent iodine(III) species are powerful reagents for oxidative C-N coupling reactions, providing access to valuable N-heterocycles. A new electrocatalytic hypervalent iodine(III)-mediated in-cell synthesis of 1H-N-aryl-3,4-dihydroquinolin-2-ones by dehydrogenative C-N bond formation is presented. Catalytic amounts of the redox mediator, a low supporting electrolyte concentration and recycling of the solvent used make this method a sustainable alternative to electrochemical ex-cell or conventional approaches. Furthermore, inexpensive, readily available electrode materials and a simple galvanostatic set-up are applied. The broad functional group tolerance could be demonstrated by synthesizing 23 examples in yields up to 96 %, with one reaction being performed on a 10-fold higher scale. Based on the obtained results a sound reaction mechanism could be proposed., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

In the first part of the study the prevalence and incidence of diagnosed Type 2 diabetes among adult rural populations of southern, central and northern areas of the Krasnoyarsk region of Siberia is compared. The six-year mean incidence of diabetes in the southern area was 0.86 per 1000 (95% CI: 0.66-1.06), in the central area this incidence was 0.79 (0.57-1.01). In contrast, in the northern area the mean Type 2 incidence among indigenous population was 0.16 per 1000 (0-0.43) and among aliens it was 0.38 (0.22-0.54). The age-standardised Type 2 diabetes prevalence in the population of southern and central areas were 10.23 (9.55-10.-92) and 10.77 (9.99-11.55), respectively. In the northern area among aliens it was 8.98 (8.18-9.78) and among indigenous peoples only 2.54 per 1000 (1.46-3.62). The second part of this study consists of a population based survey to determine the prevalence rate of Type 2 diabetes among 596 Evenks and 306 alien inhabitants in Evenkia (82% eligible participants of Baikit district). No cases of glucose intolerance were found among Evenks in this study and one case of Type 2 diabetes was confirmed among aliens (prevalence rate 3.27 per 1000). These data indicate that Type 2 diabetes is still rare among northern indigenous populations of Siberia and that diabetes in northern alien populations is less prevalent than among peoples of central and southern areas of Siberia.