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This article explores the potential of imidazo[1,2-a]pyridine-based donor-acceptor chromophores for the development of novel fluorophores and donor-acceptor chromophores. The authors conducted density functional theory calculations and proposed a modular synthesis approach to access the desired structures. The results show promising potential for the development of thermally activated delayed fluorescence emitters. The article also discusses the synthesis and characterization of a series of donor-acceptor chromophores with a 3-aminoimidazo[1,2-a]pyridine donor motif, highlighting the need for further adjustments and optimizations to improve their optoelectronic properties. The modular synthesis approach used in this study provides a versatile platform for the development of new fluorescent emitters. [Extracted from the article]

This article explores the use of bicyclopentane (BCP) as a bioisostere in medicinal chemistry. BCP can replace phenyl rings or alkynes in molecules, altering their physical properties. The authors focus on the synthesis of BCP-sulfoxides, which can enhance the pharmacological properties of compounds. They present a new method using a BCP-sulfinate precursor that is more convenient and stable. The authors successfully synthesized a previously inaccessible methyl-substituted sulfoxide and suggest the potential for further modifications. [Extracted from the article]

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]

This report describes the synthesis of a [2.2]paracyclophane‐derived annulated 3‐amino‐imidazole ligand library through a Groebke‐Blackburn‐Bienaymé three‐component reaction (GBB‐3CR) approach employing formyl‐cyclophanes in combination with diverse aliphatic and aromatic isocyanides and heteroaromatic amidines. The GBB‐3CR process gives access to skeletally‐diverse cyclophanyl imidazole ligands, namely 3‐amino‐imidazo[1,2‐a]pyridines and imidazo[1,2‐a]pyrazines. Additionally, a one‐pot protocol for the GBB‐3CR by an in situ generation of cyclophanyl isocyanide is demonstrated. The products were analyzed by detailed spectroscopic techniques, and the cyclophanyl imidazo[1,2‐a]pyridine was confirmed unambiguously by single‐crystal X‐Ray crystallography. The cyclophanyl imidazole ligands can be readily transformed to showcase their useful utility in preparing N,C‐palladacycles through regioselective ortho‐palladation. [ABSTRACT FROM AUTHOR]

Fused-imidazoles, Groebke-Blackburn-Bienaymé (GBB) reaction, Isocyanide Chemistry, Multicomponent reactions, [2.2]Paracyclophane Cover Feature: Diversity-Oriented Synthesis of [2.2]Paracyclophane-derived Fused Imidazo[1,2-a]heterocycles by Groebke-Blackburn-Bienaymé Reaction: Accessing Cyclophanyl Imidazole Ligands Library (Chem. Eur. J. 3/2022) Keywords: Fused-imidazoles; Groebke-Blackburn-Bienaymé (GBB) reaction; Isocyanide Chemistry; Multicomponent reactions; [2.2]Paracyclophane EN Fused-imidazoles Groebke-Blackburn-Bienaymé (GBB) reaction Isocyanide Chemistry Multicomponent reactions [2.2]Paracyclophane 1 1 1 01/18/22 20220113 NES 220113 B The Groebke-Blackburn-Bienaymé three-component reaction b (GBB-3CR) has contributed enormously to the progress of organic synthesis, medicinal chemistry, and materials science. [Extracted from the article]

This report describes the synthesis of a [2.2]paracyclophane‐derived annulated 3‐amino‐imidazole ligand library through a Groebke‐Blackburn‐Bienaymé three‐component reaction (GBB‐3CR) approach employing formyl‐cyclophanes in combination with diverse aliphatic and aromatic isocyanides and heteroaromatic amidines. The GBB‐3CR process gives access to skeletally‐diverse cyclophanyl imidazole ligands, namely 3‐amino‐imidazo[1,2‐a]pyridines and imidazo[1,2‐a]pyrazines. Additionally, a one‐pot protocol for the GBB‐3CR by an in situ generation of cyclophanyl isocyanide is demonstrated. The products were analyzed by detailed spectroscopic techniques, and the cyclophanyl imidazo[1,2‐a]pyridine was confirmed unambiguously by single‐crystal X‐Ray crystallography. The cyclophanyl imidazole ligands can be readily transformed to showcase their useful utility in preparing N,C‐palladacycles through regioselective ortho‐palladation. [ABSTRACT FROM AUTHOR]

Chemical vapor deposition (CVD) polymerization is a commonly used approach in surface chemistry, providing a substrate‐independent platform for bioactive surface functionalization strategies. This work investigates the Arbuzov reaction of halogenated polymer coatings readily available via CVD polymerization, using poly(4‐chloro‐para‐xylylene) (Parylene C) as a model substance. Postpolymerization modification of these coatings via catalyst‐free and UV‐induced Arbuzov reaction using phosphites results in phosphonate‐functionalized polymers. The combination of infrared reflection‐absorption spectroscopy (IRRAS), X‐ray photoelectron spectroscopy (XPS), and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) provides detailed insights into the reaction progress. Time‐dependent studies suggest that the non‐polar phosphites penetrate deep into the CVD films and react with the polymer film. In addition, ToF‐SIMS, scanning electron microscopy (SEM), and atomic force microscopy (AFM) confirm spatial control of the reaction, resulting in localized chemical and topographical surface modification, recognizable by changes in interference color, fluorescence, and wettability. Preliminary 3D fluorescence spectroscopy investigations indicate tunable near‐infrared emission of these polymer films. This work is the first step toward generating multifunctional polymer coatings based on chemically modifiable, CVD polymers with potential applications in biomaterials, sensors, or optoelectronics. [ABSTRACT FROM AUTHOR]

After more than 70 years since their discovery, Criegee intermediates (CIs) are back at the forefront of modern chemistry of short-lived reactive intermediates. They play an important role in the mechanistic context of chemical synthesis, total synthesis, pharmaceuticals, and, most importantly, climate-controlling aerosol formation as well as atmospheric chemistry. This Minireview summarizes key aspects of CIs (from the mechanism of formation, for example, by ozonolysis of alkenes and photolysis methods employing diiodo and diazo compounds, to their electronic structures and chemical reactivity), highlights the most recent findings and some landmark results of gas-phase kinetics, and detection/measurements. The recent progress in synthetic and mechanistic studies in the chemistry of CIs provides a guide to illustrate the possibilities for further investigations in this exciting field., (© 2020 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)