Transition‐Metal‐Free Acceptorless Decarbonylation of Formic Acid Enabled by a Liquid Chemical‐Looping Strategy

The selective decarbonylation of formic acid was achieved under transition‐metal‐free conditions. Using a liquid chemical‐looping strategy, the thermodynamically favored dehydrogenation of formic acid was shut down, yielding a pure stream of CO with no H₂ or CO₂ contamination. The transformation involves a two‐step sequence where methanol is used as a recyclable looping agent to yield methylformate, which is subsequently decomposed to carbon monoxide using alkoxides as catalysts.     

A Triphenylphosphine-Based Microporous Polymer for a Wittig Reaction Cycle in the Solid State

The Wittig reaction is a key step in industrial processes to synthesise large quantities of vitamin A and various other important chemicals that are used in daily life. This article presents a pathway to achieve the Wittig reaction in a solid network. A highly porous triphenylphosphine-based polymer was applied as a solid Wittig reagent that undergoes, in a multi-step cycle, in total six post-synthetic modifications. This allowed for regeneration of the solid Wittig reagent and reuse for the same reaction cycle. Of particular industrial relevance is that the newly developed material also enables a simple way of separating the product by filtration. Therefore, additional costly and difficult separation and purification steps are no longer needed.     

A Nickel(II) Nitrite Based Molecular Perovskite Ferroelectric

The X‐site ion in organic–inorganic hybrid ABX₃ perovskites (OHPs) varies from halide ion to bridging linkers like HCOO^?, N₃^?, NO₂^?, and CN^?. However, no nitrite‐based OHP ferroelectrics have been reported so far. Now, based on non‐ferroelectric [(CH₃)₄N][Ni(NO₂)₃], through the combined methodologies of quasi‐spherical shape, hydrogen bonding functionality, and H/F substitution, we have successfully synthesized an OHP ferroelectric, [FMeTP][Ni(NO₂)₃] (FMeTP=N‐fluoromethyl tropine). As an unprecedented nitrite‐based OHP ferroelectric, the well‐designed [FMeTP][Ni(NO₂)₃] undergoes the ferroelectric phase transition at 400 K with an Aizu notation of 6/mmmFm, showing multiaxial ferroelectric characteristics. This work is a great step towards not only enriching the molecular ferroelectric families but also accelerating the potential practical applications.     

Looping mechanics of rods and DNA with non-homogeneous and discontinuous stiffness

DNA molecules may form loops in response to binding with regulatory proteins that control the expression of genes. While DNA looping is a widely accepted gene regulatory mechanism, basic questions regarding the mechanics of the looping process remain open. The present paper contributes a computational rod model that accounts for non-homogeneous and discontinuous changes in stiffness to support the analysis of DNA looping. We pursue this objective in two steps. First, we illustrate the effects of non-homogeneous stiffness on the looping of generic rods under pure torsion. Results computed for this idealized case support our intuition that elastic deformation and strain energy localize in ‘soft’ regions and that equilibrium bifurcations are sensitive to non-homogenous stiffness. Next, we extend the formulation to describe the combined bending, torsion and compression induced on DNA by the LacR protein. We demonstrate that while moderate stiffness variations have only modest influence on LacR-mediated DNA looping, highly localized softening (e.g., ‘kinkable’ or ‘melted’ subdomains) may substantially reduce the energetic cost of looping and profoundly affect loop geometry.