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A photochemical cyclization of F‐tagged, o‐alkynylated N‐alkylamides to indoles catalyzed by [Ir(dF(CF3)ppy)2(dtbpy)]PF6 is presented. This straightforward and efficient reaction involves an intramolecular rearrangement due to the presence of an electron withdrawing group in the acyl moiety and is the first example of photochemically induced 1,3‐acyl shift in the cyclization towards 3‐acylindoles. A four‐step reaction sequence including the photoreaction as a key step to the desired indoles has been developed and optimized. The compatibility of differently substituted F‐tagged precursors with the photocyclization step was investigated and the robustness of this step towards modifications could be shown. In total, 16 so far unknown derivatives with diverse modifications in positions N1 and C2, bearing a pentadecafluorooctanoyl moiety as F‐tag, were synthesized in very good yields and fully characterized. [ABSTRACT FROM AUTHOR]

Fuel cells used for transport applications hold polymer membranes as a key element. Their efficiency can be significantly increased if structured ion channels are implemented at the molecular level into the proton‐conducting membrane. New functional molecules with selective affinity for ionomers are needed to obtain such a membrane design. This study presents a method to screen for selective peptide binders to perfluorinated sulfonic acid ionomers, e.g., Nafion using ultra‐high density peptide arrays with a spot size of up to 30 µm. First, the ionomer dispersion is incubated with the peptide chip containing 56014 randomly chosen 6‐mer peptides. Afterward, the peptide chip is washed. The peptide WIWHCW with the helix structure is identified as a selective binder to Nafion. The invariant amino acids responsible for binding are also determined using a peptide chip approach. The specific binding pocket of WIWHCW is formed by histidine and tryptophan. Its dissociation constant to the ionomer is measured at ≈140 µM. [ABSTRACT FROM AUTHOR]

The synthesis of linear symmetric ethynyl‐ and acetylide‐amidinates of the coinage metals is presented. Starting with the desilylation of the complexes [{Me3SiC≡CC(NDipp)2}2M2] (Dipp=2,6‐diisopropylphenyl) (M=Cu, Au) it is demonstrated that this compound class is suitable to serve as a versatile metalloligand. Deprotonation with n‐butyllithium and subsequent salt metathesis reactions yield symmetric tetranuclear gold(I) acetylide complexes of the form [{(PPh3)AuC≡CC(NDipp)2}2M2] (M=Cu, Au). The corresponding Ag complex [{(PPh3)AuC≡CC(NDipp)2}2Ag2] was obtained by a different route via metal rearrangement. All compounds show bright blue or blue‐green microsecond long phosphorescence in the solid state, hence their photophysical properties were thoroughly investigated in a temperature range of 20–295 K. Emission quantum yields of up to 41 % at room temperature were determined. Furthermore, similar emissions with quantum yields of 15 % were observed for the two most brightly luminescent complexes in thf solution. [ABSTRACT FROM AUTHOR]

In the article "Selective Peptide Binders to the Perfluorinated Sulfonic Acid Ionomer Nafion," researchers Patrizia Gartner, Alexander Nesterov-Mueller, and their colleagues discuss a new screening technique for identifying specific peptide binders for Nafion ionomers. These binders have the potential to enhance fuel cell membrane design at the molecular level. The researchers used peptide chip methodology to identify the conserved amino acids responsible for ionomer binding. This research opens up new possibilities for innovative fuel cell technology. [Extracted from the article]

The versatile metalloligand [{HC≡CC(NDipp)2}2Au2] (dipp = 2,6-diisopropylphenyl) was converted into early-late heterotetrametallic complexes [{ClCp2MC≡CC(NDipp)2}2Au2] (M = Ti, Zr). These compounds show photoluminescence with either remarkably different (Ti) or similar (Zr) features as compared to related solely coinage metal containing acetylide amidinate complexes. [ABSTRACT FROM AUTHOR]

Cover Feature: Efficient Blue Phosphorescence in Gold(I)-Acetylide Functionalized Coinage Metal Bis(amidinate) Complexes (Chem. Eur. J. 70/2020) Keywords: acetylide; amidinate; desilylation; gold; luminescence EN acetylide amidinate desilylation gold luminescence 16564 16564 1 12/18/20 20201215 NES 201215 B The synthesis of linear symmetric ethynyl- and acetylide- amidinates b of the coinage metals is presented. Acetylide, amidinate, desilylation, gold, luminescence. [Extracted from the article]