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    Researchers create ‘shortcut’ to terpene biosynthesis in E. coli

    Researchers from North Carolina State University have developed an artificial enzymatic pathway for synthesizing isoprenoids, or terpenes, in E. coli. This shorter, more efficient, cost-effective and customizable pathway transforms E. coli into a factory that can produce terpenes for use in everything from cancer drugs to biofuels. …read more

    Source:: Physorg Latest

          

    Researchers discover molecules ‘spin flip’ from magnetic to non-magnetic forms dynamically

    An unexpected discovery in Professor Arthur Suits’ chemistry lab could have implications for manufacturing more efficient solar cells and improving photodynamic therapies for treating cancer, and it may contribute to research into quantum computing. At the heart of the discovery is the spin of electrons. Molecules are either nonmagnetic or magnetic depending on whether two electrons are paired with opposite spins or unpaired with same spins. Molecules can switch from magnetic to nonmagnetic forms or vice versa in a process called flipping a spin, but Suits says that process is inefficient and happens slowly. …read more

    Source:: Physorg Latest

          

    A Facile Route to Nonlinear Optical Materials: Three‐Site Aliovalent Substitution Involving One Cation and Two Anions

    Trading places: Two new nonlinear optical materials, α‐ and β‐Ba2[GaF4(IO3)2](IO3) (1 and 2), were designed via three‐site aliovalent substitution of VO4F2 in α‐ and β‐Ba2[VO2F2(IO3)2](IO3) by GaO2F4. The new materials display large second‐harmonic generation responses (≈6×KH2PO4 (KDP)), wide energy band gaps (4.61 and 4.35 eV), and high laser damage thresholds (29.7× and 28.3× relative to that of AgGaS2).

    Abstract

    Two mixed‐metal gallium iodate fluorides, namely, α‐ and β‐Ba2[GaF4(IO3)2](IO3) (1 and 2), have been designed by the aliovalent substitutions of α‐ and β‐Ba2[VO2F2(IO3)2](IO3) (3 and 4) involving one cationic and two anionic sites. Both 1 and 2 display large second‐harmonic generation responses (≈6×KH2PO4 (KDP)), large energy band gaps (4.61 and 4.35 eV), wide transmittance ranges (≈0.27–12.5 μm), and high relevant laser‐induced damage thresholds (29.7× and 28.3×AgGaS2, respectively), which indicates that 1 and 2 are potential second‐order nonlinear optical materials in the ultraviolet to mid‐infrared. Our studies propose that three‐site aliovalent substitution is a facile route for the discovery of good NLO materials.

    …read more

    Source:: Angewandte Chemie Int. edition

          

    Access to N‐Substituted 2‐Pyridones by Catalytic Intermolecular Dearomatization and 1,4‐Acyl Transfer

    When the fearless Don Quixote was charging at windmills, he left his slow companion, Sancho Panza, behind. In their Communication (DOI: 10.1002/anie.201812937), J. Sun et al. describe a novel rhodium‐catalyzed dearomatization and rearrangement of O‐substituted pyridines to access N‐substituted 2‐pyridones, a challenging target since their straightforward synthesis by simple alkylation of 2‐pyridones is thwarted by their preferred O‐reactivity. The key to this transformation is the formation of the pyridinium ylide and subsequent 1,4‐acyl migratory rearrangement.

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    Source:: Angewandte Chemie Int. edition

          

    Helicoidal Patterning of Nanorods with Polymer Ligands

    Gold nanorods, end‐grafted with achiral polymer ligands, show a new mechanism of chiral surface patterning giving a helicoidal morphology. This morphology is dictated by the relationship between the polymer grafting density and the ratio of the polymer length to the nanorod radius.

    Abstract

    Chiral packing of ligands on the surface of nanoparticles (NPs) is of fundamental and practical importance, as it determines how NPs interact with each other and with the molecular world. Herein, for gold nanorods (NRs) capped with end‐grafted nonchiral polymer ligands, we show a new mechanism of chiral surface patterning. Under poor solvency conditions, a smooth polymer layer segregates into helicoidally organized surface‐pinned micelles (patches). The helicoidal morphology is dictated by the polymer grafting density and the ratio of the polymer ligand length to nanorod radius. Outside this specific parameter space, a range of polymer surface structures was observed, including random, shish‐kebab, and hybrid patches, as well as a smooth polymer layer. We characterize polymer surface morphology by theoretical and experimental state diagrams. The helicoidally organized polymer patches on the NR surface can be used as a template for the helicoidal organization of other NPs, masked synthesis on the NR surface, as well as the exploration of new NP self‐assembly modes.

    …read more

    Source:: Angewandte Chemie Int. edition

          

    Atomically Dispersed Molybdenum Catalysts for Efficient Ambient Nitrogen Fixation

    Electrocatalytic N2 reduction under ambient conditions offers a promising carbon‐free strategy toward clean and sustainable NH3 production. In their Communication (DOI: 10.1002/anie.201811728), J. Luo, R. R. Adzic, H. L. Xin et al. report single molybdenum atoms anchored on nitrogen‐doped porous carbon. The catalyst achieves a high NH3 yield rate, Faradaic efficiency, and stability at room temperature because of a high density of active sites within a hierarchically porous carbon framework.

    …read more

    Source:: Angewandte Chemie Int. edition

          

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