In this work, we present an ew synthetics trategy for fourfold-substituted perylene monoimides via tetrabrominated perylene monoanhydrides. X-ray diffraction analysis unveiled the intramolecular stacking orientation between the substituents and semicircular packing behavior.W eo bserved the remarkable influence of the substituent on the longevity and nature of the excited state upon visible light excitation.I nt he presenceo fp oly(dehydroalanine)-graftpoly(ethylene glycol)g raft copolymers as solubilizing template, the chromophores are capable of sensitizing [Mo 3 S 13 ] 2À clustersi na queous solution for stable visible light driven hydrogen evolution over three days.

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We report on a photocatalytic setup that utilizes the organic photosensitizer (PS) diiodo-BODIPY and the non-precious-metal-based hydrogen evolution reaction (HER) catalyst (NH4)2[Mo3S13] together with a polyampholytic unimolecular matrix poly(dehydroalanine)-graft-poly(ethylene glycol) (PDha-g-PEG) in aqueous media. The system shows exceptionally high performance with turnover numbers (TON > 7300) and turnover frequencies (TOF > 450 h–1) that are typical for noble-metal-containing systems. Excited-state absorption spectra reveal the formation of a long-lived triplet state of the PS in both aqueous and organic media. The system is a blueprint for developing noble-metal-free HER in water. Component optimization, e.g., by modification of the meso substituent of the PS and the composition of the HER catalyst, is further possible.

This study describes the first example for shielding of a high performing terpolymer that consists of N‐(2‐hydroxypropyl)methacrylamide (HPMA), N‐(3‐guanidinopropyl)methacrylamide (GPMA), and N‐(2‐indolethyl)methacrylamide monomers (IEMA) by block copolymerization of a polyethylene glycol derivative – poly(nona(ethylene glycol)methyl ether methacrylate) (P(MEO9MA)) via reversible addition–fragmentation chain transfer (RAFT) polymerization. The molecular weight of P(MEO9MA) is varied from 3 to 40 kg mol–1 while the comonomer content of HPMA, GPMA, and IEMA is kept comparable. The influence of P(MEO9MA) block with various molecular weights is investigated over cytotoxicity, plasmid DNA (pDNA) binding, and transfection efficiency of the resulting polyplexes. Overall, the increase in molecular weight of P(MEO9MA) block demonstrates excellent biocompatibility with higher cell viability in L‐929 cells and an efficient binding to pDNA at N/P ratio of 2. The significant transfection efficiency in CHO‐K1 cells at N/P ratio 20 is obtained for block copolymers with molecular weight of P(MEO9MA) up to 10 kg mol–1. Moreover, a fluorescently labeled analogue of P(MEO9MA), bearing perylene monoimide methacrylamide (PMIM), is introduced as a comonomer in RAFT polymerization. Polyplexes consisting of labeled block copolymer with 20 kg mol–1 of P(MEO9MA) and pDNA are incubated in Hela cells and investigated through structured illumination microscopy (SIM).

In this work, we present two bipyridine-annulated perylene tetracarboxylic ester (P-L) photocatalysts with PtCl2 and PdCl2. X-ray photoelectron spectroscopy showed that their binding energies match precisely the binding energies of the respective M(bpy)Cl2 complexes. Cyclic voltammetry measurements of the complexes displayed additional reduction potentials upon metal insertion. Light-driven catalysis demonstrated that both compounds are catalytically active, with P-Pt outcompeting P-Pd with a TON of 186 over 48 h in the presence of ascorbic acid (P-Pd: 50). Mercury poisoning experiments were carried out to validate the catalytically competent component. Almost quantitative quenching of the catalytic turnover was observed for P-Pd, whereas the hydrogen production rate remained unaffected for P-Pt, making it a photocatalyst that contains the structure PtN^NCl2 and nonetheless operates without a second noble metal nucleus or a separate photosensitizer under visible light. Time-resolved (fs and ns) spectroscopy on P-L and P-Pt yields insights into the light-induced intramolecular processes. In P-Pt, we observed that both 1IL (400 nm) and 1MLCT (500 nm) excitation leads to intersystem crossing with a solvent polarity-dependent distribution between 3MLCT and 3IL, where the 3IL population increases in ACN vs DCM, indicating that in aqueous catalytic samples, the 3IL state plays a major role in the catalytic process.

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