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On a Wendelstein 7-X (W7-X), an alkali metal beam (AMB) diagnostic system was installed in order to measure the plasma edge electron density profiles and turbulence transport. A sodium beam was injected in the plasma, and the light emission was observed by an optical system. During the last operation phase, OP1.2b campaign trial spectral measurements were performed with a dedicated optical branch. The results showed the emergence of potential CX lines in the light spectra during sodium injection. The lines were identified as Carbon III, which were the dominant lines observed by other diagnostics at the edge plasma. Based on these results, an additional dedicated optical system was developed and installed in 2021 for the upcoming operational phase, OP2. The optics were designed for multiple purposes: spectral measurements for the AMB system and for a He/Ne gas jet. The system was designed to allow implementation of further diagnostics on this port later (e.g., coherence imaging system). The details of the implementation of the design requirements and the main challenges of the manufacturing process and installation are discussed in this paper. [ABSTRACT FROM AUTHOR]

The active site of particulate methane monooxygenase (pMMO) and its mechanism of action are not known. Recently, the CuC site emerged as a potential active site, but to date it lacks any study on biomimetic resemblance of the coordination environment provided by the enzyme. Here, the synthesis of a cage ligand providing such an environment is reported. Copper is incorporated, and coordination occurs by the two imidazole and one carboxylate group offered by the ligand. Depending on the oxidation state, it can adopt different coordination modes, as evidenced by the solid‐state structures and computational investigation. The copper(I) state readily reacts with dioxygen and thereby undergoes CH activation. Moreover, the catalytic aerobic oxidation of hydroquinones as ubiquinol mimics is shown. Clean one‐electron oxidation occurs under mild conditions and EPR analysis of the copper(II) state in the presence of water reveals striking similarities to the data obtained from pMMO. [ABSTRACT FROM AUTHOR]

Keywords: bioinorganic chemistry; confined space; organocatalysis; self-assembly; size-selective catalysis EN bioinorganic chemistry confined space organocatalysis self-assembly size-selective catalysis 1 1 1 05/11/23 20230508 NES 230508 B The Front Cover b illustrates the self-assembly of a cartoon parachute group conducting experiments. Bioinorganic chemistry, confined space, organocatalysis, self-assembly, size-selective catalysis Front Cover: Reactions in Endohedral Functionalized Cages (Eur. J. Org. [Extracted from the article]

The active site of particulate methane monooxygenase (pMMO) and its mechanism of action are not known. Recently, the Cu C site emerged as a potential active site, but to date it lacks any study on biomimetic resemblance of the coordination environment provided by the enzyme. Here, the synthesis of a cage ligand providing such an environment is reported. Copper is incorporated, and coordination occurs by the two imidazole and one carboxylate group offered by the ligand. Depending on the oxidation state, it can adopt different coordination modes, as evidenced by the solid-state structures and computational investigation. The copper(I) state readily reacts with dioxygen and thereby undergoes CH activation. Moreover, the catalytic aerobic oxidation of hydroquinones as ubiquinol mimics is shown. Clean one-electron oxidation occurs under mild conditions and EPR analysis of the copper(II) state in the presence of water reveals striking similarities to the data obtained from pMMO., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

C-H amination and amidation by catalytic nitrene transfer are well-established and typically proceed via electrophilic attack of nitrenoid intermediates. In contrast, the insertion of (formal) terminal nitride ligands into C-H bonds is much less developed and catalytic nitrogen atom transfer remains unknown. We here report the synthesis of a formal terminal nitride complex of palladium. Photocrystallographic, magnetic, and computational characterization support the assignment as an authentic metallonitrene (Pd-N) with a diradical nitrogen ligand that is singly bonded to Pd II . Despite the subvalent nitrene character, selective C-H insertion with aldehydes follows nucleophilic selectivity. Transamidation of the benzamide product is enabled by reaction with N 3 SiMe 3 . Based on these results, a photocatalytic protocol for aldehyde C-H trimethylsilylamidation was developed that exhibits inverted, nucleophilic selectivity as compared to typical nitrene transfer catalysis. This first example of catalytic C-H nitrogen atom transfer offers facile access to primary amides after deprotection., (© 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

An azide masked amine is used to obtain a cage of lower symmetry that possess one terpy-group in an exo -position. This group can coordinate to iron(ii), yielding selectively an easy to purify Fe(terpy-cage) 2 dumbbell. The dumbbell can also be obtained in a one pot reaction, which proceeded without isolation of the exo -functionalized cage., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)