The narrowest armchair graphene nanoribbon (AGNR) with five carbons across the width of the GNR (5-AGNR) was synthesized on Au(111) surfaces via sequential dehalogenation processes in a mild condition by using 1,4,5,8-tetrabromonaphthalene as the molecular precursor. Gold-organic hybrids were observed by using high-resolution scanning tunneling microscopy and considered as intermediate states upon AGNR formation. Scanning tunneling spectroscopy reveals an unexpectedly large band gap of Δ = 2.8 ± 0.1 eV on Au(111) surface which can be interpreted by the hybridization of the surface states and the molecular states of the 5-AGNR.

An efficient method to synthesize 3,4,9,10-tetrabromoperylenes is reported under optimized Hunsdiecker conditions. Various octasubstituted perylenes were obtained by reaction of 1,6,7,12-tetrachloro-3,4,9,10-tetrabromoperylene with phenol, trimethylsilyl chloride, cooper cyanide, or sulfur via metal-catalyzed couplings or nucleophilic substitutions. These new perylenes show completely different optical and redox properties, thus opening a facile way to develop new chromophophore structures.

Soluble ultra-narrow armchair graphene nanoribbons (AGNRs) with length of ≈20 nm and completely fused cores exceeding 5 nm in length, pronounced near-infrared (NIR) absorption up to 1400 nm, and a low band gap (≈0.9 eV) are synthesized from 3,9(3,10)-dibromoperylene and 3,4,9,10-tetrabromoperylene. Since the monomers are obtained from perylene carboxyanhydrides, a remarkable link between dye and graphene chemistry is established. The two-step protocol for the AGNR synthesis by aryl-aryl coupling and subsequent cyclodehydrogenation is compared with a direct Yamamoto polymerization. Ultrafast photoconductivity analysis by optical pump-terahertz (THz) probe spectroscopy of the longest AGNRs excited in the NIR regime (800 nm) reveal their high intrinsic charge carrier mobility.

The self-assembly of an amphiphilic monomolecular electron acceptor-donor dyad into electroactive π-π stacked fibrillar structures can be triggered by irradiation with visible light. These fibers, exposing hydrophilic ethylene glycol in their external shell, show unique characteristics as resistive humidity sensors that exhibit high sensitivity and ultrafast response.

Biocompatible organic dyes emitting in the near-infrared are highly desirable in fluorescence imaging techniques. Herein we report a synthetic approach for building novel small peri-guanidine-fused naphthalene monoimide and perylene monoimide chromophores. The presented structures possess near-infrared absorption and emission, high photostability, and good water solubility. After a fast cellular uptake, they selectively stain mitochondria with a low background in live and fixed cells. They can be additionally modified in a one-step reaction with functional groups for covalent labeling of proteins. The low cytotoxicity allows a long time exposure of live cells to the dyes without the necessity of washing. Successful application in localization super-resolution microscopy was demonstrated in phosphate-buffered saline without any reducing or oxidizing additives.

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.

Synthetic models of the active site of [FeFe]-hydrogenase containing naphthalene monoimide (NMI) of peri-substituted dichalcogenides as bridging linkers have been prepared and characterized using different spectroscopic methods. The influence of the imide functionality and the chalcogen atoms on the redox properties and the catalytic behaviour of complexes 7-10 was studied using cyclic voltammetry. The results revealed that the imide functionality has improved the chemical stability of the reduced species and the replacement of the S atoms by Se caused a cathodic shift in the oxidation peaks. Moreover, the optical properties of compounds 1, 2, 4, and 5 and the respective diiron complexes 7-10 were investigated by UV-Vis absorption and fluorescence spectroscopy assisted by quantum chemical simulations. The structures of complexes 6-9 were confirmed by X-ray diffraction analysis.

An efficient synthesis of 9,10-dibromo-1,6,7,12-tetrachloro-perylene-3,4-dicarboxylic acid monoimides from easily available 1,6,7,12-tetrachloro-perylene-3,4,9,10-tetracarboxylic acid dianhydride is reported. Therefrom, unprecedented perylene monoimides with pronounced donor-acceptor character were obtained via twofold aromatic amination. The halogen substituents in the 1,6,7,12-positions of perylene were removed under basic conditions. To the best of our knowledge, this is the first efficient synthetic route toward 9,10-doubly functionalized perylene-3,4-dicarboxylic acid monoimides.