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This research is performed on a selection of archaeological glass finds with corresponding soil samples, excavated on the site of the High Medieval castle Cucagna in Friuli/Northern Italy. In the frame of understanding medieval glass technology and the chemical–physical conditions that influenced the state of preservation of the glass finds, this study uses a multi-analytical line-up of methods to characterize the composition of the glass and basic parameters of the soil including texture, mineralogical composition, pH, redox potential (Eh) and electric conductivity (EC). The results show that glass corrosion in soil not only depends on acidity, alkalinity or glass composition but also on the texture of the soil, measurable as grain-size distribution, and the mineralogical composition. The compositional groups of the glassware from Cucagna indicate the use of various raw material sources, pointing to Northern and Central Italian glass workshops with primary or secondary glass production.

We report a novel example of electro‐mediated photoredox catalysis (e‐PRC) in the reductive cleavage of C(sp3)−O bonds of phosphinated alcohols to alkyl carbanions. As well as deoxygenations, olefinations are reported which are E‐selective and can be made Z‐selective in a tandem reduction/photosensitization process where both steps are photoelectrochemically promoted. Spectroscopy, computation, and catalyst structural variations reveal that our new naphthalene monoimide‐type catalyst allows for an intimate dispersive precomplexation of its radical anion form with the phosphinate substrate, facilitating a reactivity‐determining C(sp3)−O cleavage. Surprisingly and in contrast to previously reported photoexcited radical anion chemistries, our conditions tolerate aryl chlorides/bromides and do not give rise to Birch‐type reductions. [ABSTRACT FROM AUTHOR]

This research is performed on a selection of archaeological glass finds with corresponding soil samples, excavated on the site of the High Medieval castle Cucagna in Friuli/Northern Italy. In the frame of understanding medieval glass technology and the chemical–physical conditions that influenced the state of preservation of the glass finds, this study uses a multi-analytical line-up of methods to characterize the composition of the glass and basic parameters of the soil including texture, mineralogical composition, pH, redox potential (Eh) and electric conductivity (EC). The results show that glass corrosion in soil not only depends on acidity, alkalinity or glass composition but also on the texture of the soil, measurable as grain-size distribution, and the mineralogical composition. The compositional groups of the glassware from Cucagna indicate the use of various raw material sources, pointing to Northern and Central Italian glass workshops with primary or secondary glass production. [ABSTRACT FROM AUTHOR]

Keywords: Elektrophotokatalyse; Photoelektrochemie; Photoredoxkatalyse; Vorassemblierung; Wasserstoffatomtransfer DE Elektrophotokatalyse Photoelektrochemie Photoredoxkatalyse Vorassemblierung Wasserstoffatomtransfer 1 1 1 03/11/22 20220314 NES 220314 B Molekulare Photoelektrochemie b , nur einen Katzensprung entfernt, entwickelt sich zu einem vielseitigen Werkzeug für die Synthese und selektive Funktionalisierung komplexer Moleküle. Die molekulare Photoelektrochemie erlaubt den Zugang zu einem breiteren Spektrum umweltfreundlicher Einelektronentransfer-Chemie. In ihrem Aufsatz (e202107811) beleuchten Joshua Barham et al. aufregende synthetische Möglichkeiten, mechanistische Einblicke und sich fortentwickelnde Reaktorplattformen, welche das Screening und die Skalierbarkeit von Reaktionen ermöglichen. [Extracted from the article]

Keywords: electrophotocatalysis; hydrogen atom transfer; photoelectrochemistry; photoredox catalysis; preassembly EN electrophotocatalysis hydrogen atom transfer photoelectrochemistry photoredox catalysis preassembly 1 1 1 03/11/22 20220314 NES 220314 B Molecular photoelectrochemistry b , allowing access to a broader window of single electron transfer chemistry in a greener way, is a rapidly expanding toolbox for synthesis and selective functionalizations of complex molecules. Inside Cover: Synthetic Molecular Photoelectrochemistry: New Frontiers in Synthetic Applications, Mechanistic Insights and Scalability (Angew. Electrophotocatalysis, hydrogen atom transfer, photoelectrochemistry, photoredox catalysis, preassembly. [Extracted from the article]

Synthetic photoelectrochemistry (PEC) is receiving increasing attention as a new frontier for the generation and handling of reactive intermediates. PEC permits selective single-electron transfer (SET) reactions in a much greener way and broadens the redox window of possible transformations. Herein, the most recent contributions are reviewed, demonstrating exciting new opportunities, namely, the combination of PEC with other reactivity paradigms (hydrogen-atom transfer, radical polar crossover, energy transfer sensitization), scalability up to multigram scale, novel selectivities in SET super-oxidations/reductions and the importance of precomplexation to temporally enable excited radical ion catalysis., (© 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)