Daniel Perleth

Nature Chemistry, Published online: 18 March 2024; doi:10.1038/s41557-024-01482-4

The spontaneous recombination of photogenerated radicals surrounded by solvent molecules is an important energy-wasting elementary step in photoredox reactions. Now the decisive role that cage escape plays in these reactions is shown in three benchmark photocatalytic reactions, with quantitative correlations observed between photoredox product formation rates and cage escape quantum yields.

Nature Chemistry, Published online: 27 January 2022; doi:10.1038/s41557-021-00850-8

Decoupling the processes of light harvesting and catalytic hydrogen evolution could be a potentially important step in storing solar energy. This has now been achieved with a single molecular unit: a light-harvesting ruthenium complex–polyoxometalate dyad that absorbs light, separates and stores charge and then generates hydrogen on demand following the addition of a proton donor.

Nature Chemistry, Published online: 25 March 2021; doi:10.1038/s41557-021-00652-y

Molecular catalysts can be made more practical by anchoring them onto electrode surfaces, but such systems are less stable than standard heterogeneous electrocatalysts. Now, supramolecular hosts bound to electrode surfaces have enabled the immobilization of molecular electrocatalysts through host–guest interactions. Desorbed or degraded guest molecules can be replaced with fresh guest molecules, extending their lifetimes.

While dinuclear Pd^I complexes first received attention for being excellent pre‐catalysts that lead to high cross‐coupling reactivities, more recent work has uncovered that direct dinuclear catalysis can also take place and reaction modes are accessible which are not amenable to Pd⁰/Pd^II cycles. This Minireview highlights the use of dinuclear Pd^I complexes in catalysis showcasing their unique reactivity and selectivity.

Abstract

Dinuclear Pd^I complexes have found widespread applications as diverse catalysts for a multitude of transformations. Initially their ability to function as pre‐catalysts for low‐coordinated Pd⁰ species was harnessed in cross‐coupling. Such Pd^I dimers are inherently labile and relatively sensitive to oxygen. In recent years, more stable dinuclear Pd^I−Pd^I frameworks, which feature bench‐stability and robustness towards nucleophiles as well as recoverability in reactions, were explored and shown to trigger privileged reactivities via dinuclear catalysis. This includes the predictable and substrate‐independent, selective C−C and C−heteroatom bond formations of poly(pseudo)halogenated arenes as well as couplings of arenes with relatively weak nucleophiles, which would not engage in Pd⁰/Pd^II catalysis. This Minireview highlights the use of dinuclear Pd^I complexes as both pre‐catalysts for the formation of highly active Pd⁰ and Pd^II−H species as well as direct dinuclear catalysts. Focus is set on the mechanistic intricacies, the speciation and the impacts on reactivity.

Nature Chemistry, Published online: 14 September 2020; doi:10.1038/s41557-020-0520-6

The vast majority of species capable of converting dinitrogen to ammonia rely on transition metals. Now, a boron compound has been shown to mediate the one-pot binding, cleavage and reduction of N2 to ammonium salts under mild conditions through a complex cascade mechanism involving multiple reduction–protonation sequences.

<p class="Standard"><span lang="EN‐US" style="color:black">Advanced applications of the Nobel Prize winning olefin metathesis reaction requires user‐friendly and highly universal catalysts. From many successful metathesis catalysts, belonging to two distinct classes of Schrock and Grubbs type catalysts, the sub‐class of the chelating‐benzylidene ruthenium complexes (so‐called Hoveyda‐Grubbs catalysts) additionally activated by Electron Withdrawing Groups (EWGs) provided a highly tunable platform. In the present review the origin of the EWG‐activation concept and selected applications of the resulted catalysts in ta</span><span lang="EN‐US">rget oriented synthesis, medicinal chemistry, as well as in preparation of fine chemicals and in material chemistry is discussed. Based on the discussed examples some suggestions for the end‐users regarding minimization of catalysts loading, selectivity control and general optimization hints of the olefin metathesis reaction are provided.<o:p></o:p></span></p>

While the art of DNA origami has been investigated extensively in recent years and demonstrated to work in a reliable manner, precise engineering of such patterns with polymers represents an emerging topic. Compared to conventional top‐down approaches ( i.e. lithography) or bottom‐up functionalization tech­niques ( i.e. self‐assembly), the com­bination of DNA origami nano­structures and polymers pro­vides a new toolbox to access defined structures in the 100 nm range. In general, DNA origami serves as a versatile template for the highly specific arrangement of polymer chains. Polymeric DNA hybrid nanostructures can either be created by growing the polymer from the DNA template or by attaching preformed polymers to the DNA scaffold. These conjugations can be of a covalent nature or be based on base‐pair hybridization between respectively modified polymers and DNA origami. Furthermore, the negatively charged DNA backbone permits interaction with positively charged poly­electro­lytes forming stable complexes. The combination of polymers with tuneable characteristics and DNA origami allows the creation of a new class of hybrid materials, which could offer exciting platforms for controlling energy transfer, nanoscale or­ga­nic circuits or the templated synthesis of nanopatterned poly­meric structures.