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The field of bioorthogonal chemistry has revolutionized our ability to interrogate and manipulate biological systems at the molecular level. However, the range of chemical reactions that can operate efficiently in biological environments without interfering with the native cellular machinery, remains limited. In this context, the rapidly growing area of photocatalysis offers a promising avenue for developing new type of bioorthogonal tools. The inherent mildness, tunability, chemoselectivity, and external controllability of photocatalytic transformations make them particularly well-suited for applications in biological and living systems. This minireview summarizes recent advances in bioorthogonal photocatalytic technologies, with a particular focus on their potential to enable the selective generation of designed products within biologically relevant or living settings., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Within the emerging field of bismuth redox catalysis, the catalytic formation of C-C bonds using aryl halides would be highly desirable; yet such a process remains a synthetic challenge. Herein, we present a chemoselective bismuth-photocatalyzed activation and subsequent coupling of (hetero)aryl iodides with pyrrole derivatives to access C(sp 2 )-C(sp 2 ) linkages through C-H functionalization. This unique reactivity is the result of the bismuth complex featuring two redox state-dependent interactions with light, which 1) activates the Bi(I) complex for oxidative addition via MLCT, and 2) promotes the homolytic cleavage of aryl Bi(III) intermediates through a LLCT process., (© 2024 The Author(s). Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Whereas indications of radical reactivity in bismuth compounds can be traced back to the 19 th century, the preparation and characterization of both transient and persistent bismuth-radical species has only been established in recent decades. These advancements led to the emergence of the field of bismuth radical chemistry, mirroring the progress seen for other main-group elements. The seminal and fundamental studies in this area have ultimately paved the way for the development of catalytic methodologies involving bismuth-radical intermediates, a promising approach that remains largely untapped in the broad landscape of synthetic organic chemistry. In this review, we delve into the milestones that eventually led to the present state-of-the-art in the field of radical bismuth chemistry. Our focus aims at outlining the intrinsic discoveries in fundamental inorganic/organometallic chemistry and contextualizing their practical applications in organic synthesis and catalysis., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Enabling self-healing of materials is crucially important for saving resources and energy in numerous emerging applications. While strategies for the self-healing of polymers are advanced, mechanisms for semiconducting inorganic materials are scarce due to the lack of suitable healing agents. Here a concept for the self-healing of metal oxides is developed. This concept consists of metal oxide nanoparticle growth inside the bulk of halogenated polymers and their subsequent entropy-driven migration to externally induced defect sites, leading to recovery of the defect. Herein, it is demonstrated that the pool of self-healing materials is expanded to include semiconductors, thereby increasing the reliability and sustainability of functional materials through the use of metal oxides. It is revealed that electrical properties of tin-doped indium oxide can be partially restored upon healing. Such properties are of immediate interest for the further development of transparent flexible electrodes., (© 2022 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

We report a state-of-the-art spectroscopic study of an archetypical barbaralone, conclusively revealing the valence tautomerism phenomena for this bistable molecular system. The two distinct 1- and 5-substituted valence tautomers have been isolated in a supersonic expansion for the first time and successfully characterized by high-resolution rotational spectroscopy. This work provides irrefutable experimental evidence of the [3,3]-rearrangement in barbaralones and highlights the use of rotational spectroscopy to analyze shape-shifting mixtures. Moreover, this observation opens the window toward the characterization of new fluxional systems in the isolation conditions of the gas phase and should serve as a reference point in the general understanding of valence tautomerism., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The formal (4+3) cycloaddition of 1,3-dienes with Rh(II) and Au(I) non-acceptor vinyl carbenes, generated from vinylcycloheptatrienes or alkoxyenynes, respectively, leads to 1,4-cycloheptadienes featuring complex and diverse substitution patterns, including natural dyctiopterene C' and a hydroxylated derivative of carota-1,4-diene. A complete mechanistic picture is presented, in which Au(I) and Rh(II) non-acceptor vinyl carbenes were shown to undergo a vinylcyclopropanation/Cope rearrangement or a direct (4+3) cycloaddition that takes place in a non-concerted manner., (© 2020 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Rhodium carbenes are key intermediates in a range of cycloadditions and insertion reactions. Herein, we report the first generation of donor Rh II carbenes by decarbenation of 7-substituted 1,3,5-cycloheptatrienes. This discovery unlocks an improved retro-Buchner-cyclopropanation sequence, a Si-H insertion reaction for a broad-scope synthesis of allylsilanes, and a new method for the vinylogation of aldehydes. The last strategy led to the development of an iterative synthesis of E-polyenes, and to the total synthesis of navenones B and C., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The formal (3+2) cycloaddition between terminal allenes and aryl or styryl gold(I) carbenes generated by a retro-Buchner reaction of 7-substituted 1,3,5-cycloheptatrienes led to indenes and cyclopentadienes, respectively. These cycloaddition processes have been applied to the construction of the carbon skeleton of the cycloaurenones and the dysiherbols as well as to the total synthesis of (±)-laurokamurene B., (© 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Hierarchical micro-/nano-structures made easy. By using extremely rough, chemically etched microstructured aluminium foils, anodization in phosphoric acid under very harsh conditions, e.g., 10 wt% phosphoric acid and room temperature, can be repeatedly accomplished without suffering from breakdown. As a result, an alumina membrane with a three-dimensionally distributed nanopore structure is formed, which can be used as a general template to fabricate hierarchical micro-/nano-structures., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Highy crystalline NiO nanoparticles are uniformly grown on the walls of carbon nanotubes (CNTs) by atomic layer deposition (ALD) at moderate temperature.Their size and stoichiometry are controlled by the ALD process parameters. The obtained NiO/CNT hybrids exhibit excellent performance in the electro-oxidation of methanol., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A flexible, nondestructive, and cost-effective replication technique for nanostructures is presented. The advantages of the process are: 1) it allows for tailoring structural parameters of the replica (e.g., line width) nearly independent of the structural geometry of the master; 2) it allows for replication of high-aspect-ratio structures also in polymer materials from solution (especially noncurable polymers) such as polystyrene and polymethylmethacrylate; 3) it includes an easy separation process, thus preserving the master for repeated use. Linear grating replicas with line widths ranging from 88 to 300 nm are obtained using a single nanostructured master. Nanofibers and complex nanopatterned replicas are achievable. The presented technique and its flexibility show that atomic layer deposition is a unique tool for the preparation of high-efficiency polarizer diffractive optics, photonics, electronics, and catalysts.

New uses for ALD: By applying standard metal oxide atomic layer deposition (ALD) to two types of porphyrins, site-specific chemical infiltration of substrate molecules is achieved: Diethylzinc can diffuse into the interior of porphyrin supramolecular structures and induce metalation of the porphyrin molecules from the vapor phase. A = Ph, p-HO(3)SC(6)H(4).