The covalent attachment of molecular photosensitizers (PS) to polyoxometalates (POMs) opens new pathways to PS‐POM dyads for light‐driven charge‐transfer and charge‐storage. Here, we report a synthetic route for the covalent linkage of BODIPY‐dyes to Anderson‐type polyoxomolybdates by using CLICK chemistry (i. e. copper‐catalyzed azide‐alkyne cycloaddition, CuAAC). Photophysical properties of the dyad were investigated by combined experimental and theoretical methods and highlight the role of both sub‐components for the charge‐separation properties. The study demonstrates how CLICK chemistry can be used for the versatile linkage of organic functional units to molecular metal oxide clusters.

Moritz F. Kuehnel opened a discussion of the paper by Andrew I. Cooper: What do you know about the HOMO and LUMO localisation on the polymers? I suppose this is strongly affected by introducing heteroatoms such as sulfur, and that this causes the changes observed when oxidising the thiophene to sulfolane moieties. Can you use different heteroatoms to tweak the redox potentials? Andrew I. Cooper answered: Yesby changing the heteroatom one can change the catalytic activity, but this can also change a variety of other things such as the surface hydrophilicity and (in some cases) the polymer molecular weight, or, in the case of networks, the surface area. As such, it is oen unclear whether these effects come from changes to the redox potentials or a variety of factors.Moritz F. Kuehnel asked: How much is known about the residual palladium in the polymer? What do you know about its environment, which I assume will depend on functional groups in the polymer backbone, e.g. donor groups? I am wondering if the observed differences in activity for different polymers are a result of the different palladium environments, rather than other, more easily determined factors. such as the band gap, etc. Do you have any EXAFS data?

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The new bis(bidentate) tetraphosphane cis,trans,cis‐1,2,3,4‐tetrakis(diphenylphosphanyl)buta‐1,3‐diene (dppbd) (7) was obtained by applying a photochemical synthetic protocol. The key step of the photochemical reaction consisted of an intramolecular [2+2] cycloaddition involving a C–C double and triple bond of the Pt‐dimer species of the formula [Pt2Cl4(dppa)(trans‐dppen)] (2) {dppa = 1,2‐bis(diphenylphosphanyl)acetylene and dppen = 1,2‐bis(diphenylphosphanyl)ethene} leading to [Pt2Cl4(dppbd)] (5). The asymmetrically bridged precursor complex 2 was obtained by combinatorial chemistry. Single crystal X‐ray structure analyses of 2 and 5 proved that the intramolecular photochemical reaction occurred. Cyanolysis of 5 gave 7, which was oxidized to dppbdO4 (8). Compounds 7, 8, and the PdII dimer complex [Pd2Cl4(dppbd)] (9) were characterized in the solid state by a single‐crystal X‐ray structure analysis. Interesting photophysial properties emerged from the UV/Vis spectra acquired for 7 and the dimer Os complexes meso‐Δ,Λ/Λ,Δ‐[Os2(bpy)4(dppbd)](PF6)4 (10) and rac‐Δ,Δ/Λ,Λ‐[Os2(bpy)4(dppbd)](PF6)4 (11).

The Front Cover shows the important steps of the synthesis of dppbd. After the formation of the initial intermediate, comes the second and key step, which is a light induced pericyclic cycloaddition, immediately followed by a thermally induced ring opening reaction. The third step is the removal of platinum, which was used as a template. The last step shows two examples of the coordination of metal centers. In the background is an excitation/emission spectrum of a compound consisting of osmium and the title compound, demonstrating its application as a photosensitizer. More information can be found in the https://doi.org/10.1002/ejic.201800804 For more on the story behind the cover research, see the https://doi.org/10.1002/ejic.201801436.

Invited for the cover of this issue is the group of Peter Brüggeller from the University of Innsbruck, Austria. The cover image shows the multi‐step synthesis of dppbd.