• Issue

    Angewandte Chemie International Edition: Volume 61, Issue 5

    January 26, 2022

Cover Pictures

Free Access

Cover Picture: Bimetallic Copper/Ruthenium/Osmium Complexes: Observation of Conformational Differences Between the Solution Phase and Solid State by Atomic Pair Distribution Function Analysis (Angew. Chem. Int. Ed. 5/2022)

  • First Published: 20 December 2021
Cover Picture: Bimetallic Copper/Ruthenium/Osmium Complexes: Observation of Conformational Differences Between the Solution Phase and Solid State by Atomic Pair Distribution Function Analysis (Angew. Chem. Int. Ed. 5/2022) Volume 61 Issue 5, 2022

The solution-phase molecular structure of five redox- and photo-active bimetallic complexes was directly probed using high-energy X-ray scattering and atomic pair distribution function analysis in the Research Article by Xiaosong Li, Karen L. Mulfort et al. (e202111764). The analysis reveals significant conformational differences between the solution-phase and solid-state structures of these complexes that may be relevant for interactions between the two metal centers.

Free Access

Inside Cover: Stable Isotope Phosphate Labelling of Diverse Metabolites is Enabled by a Family of 18O-Phosphoramidites (Angew. Chem. Int. Ed. 5/2022)

  • First Published: 10 January 2022
Inside Cover: Stable Isotope Phosphate Labelling of Diverse Metabolites is Enabled by a Family of 18O-Phosphoramidites (Angew. Chem. Int. Ed. 5/2022) Volume 61 Issue 5, 2022

18O-labelled condensed phosphates can be synthesized with a family of 18O-phosphoramidite reagents, as reported by Henning J. Jessen and co-workers in their Research Article (e202112457). “Heavy” phosphoramidites, based on a 4-hydroxyphenol core, are equipped with 18O-isotopes derived from H218O. The toolbox includes a versatile array of protecting groups, removable by acid, base, or fluoride upon self-immolation of a quinone methide. Straightforward access to major classes of biologically relevant 18O-phosphorylated metabolites is demonstrated, including nucleotides, inositol phosphates, and inorganic polyphosphates.

Free Access

Inside Back Cover: Generation of Oxyphosphonium Ions by Photoredox/Cobaloxime Catalysis for Scalable Amide and Peptide Synthesis in Batch and Continuous-Flow (Angew. Chem. Int. Ed. 5/2022)

  • First Published: 20 December 2021
Inside Back Cover: Generation of Oxyphosphonium Ions by Photoredox/Cobaloxime Catalysis for Scalable Amide and Peptide Synthesis in Batch and Continuous-Flow (Angew. Chem. Int. Ed. 5/2022) Volume 61 Issue 5, 2022

Amides are ubiquitous in biological and medicinal chemistry. In their Research Article (e202112668), Jiannan Zhao and co-workers report an “oxidation–reduction condensation” reaction through the use of PPh3 as an organic reductant. Synergistic cooperation between a Co(III) and an Ir(III) photoredox catalyst captures electrons from phosphorus and facilitates the formation of acyloxyphosphonium species, which enable direct amidation. The synthetic utility of this photocatalytic method is highlighted by rapid gram-scale peptide synthesis and successful assembly of a tetrapeptide through SPPS.

Free Access

Back Cover: Unravelling Channel Structure–Diffusivity Relationships in Zeolite ZSM-5 at the Single-Molecule Level (Angew. Chem. Int. Ed. 5/2022)

  • First Published: 23 December 2021
Back Cover: Unravelling Channel Structure–Diffusivity Relationships in Zeolite ZSM-5 at the Single-Molecule Level (Angew. Chem. Int. Ed. 5/2022) Volume 61 Issue 5, 2022

Single-molecule tracking is used to follow the motion of individual molecules. In their Communication (e202114388), Bert M. Weckhuysen and co-workers compare the molecules’ motion behavior in different zeolite channel geometries at the single-molecule level. This approach provides mechanistic insight into the channel geometry–diffusivity relationships and the enhancement of diffusion in hierarchical zeolites.

Frontispiece

Free Access

Frontispiece: Aggregation-Enhanced Sonodynamic Activity of Phthalocyanine–Artesunate Conjugates

  • First Published: 18 January 2022
Frontispiece: Aggregation-Enhanced Sonodynamic Activity of Phthalocyanine–Artesunate Conjugates Volume 61 Issue 5, 2022

Sonosensitizers An aggregation-enhanced sonodynamic activity (AESA) effect is reported by Mei-Rong Ke, Jian-Dong Huang et al. in their Communication (e202113506). The AESA effect could open up a new avenue for the development of efficient sonosensitizers.

Free Access

Frontispiece: Creating Dynamic Nanospaces in Solution by Cationic Cages as Multirole Catalytic Platform for Unconventional C(sp)−H Activation Beyond Enzyme Mimics

  • First Published: 18 January 2022
Frontispiece: Creating Dynamic Nanospaces in Solution by Cationic Cages as Multirole Catalytic Platform for Unconventional C(sp)−H Activation Beyond Enzyme Mimics Volume 61 Issue 5, 2022

Supramolecular Catalysis In their Research Article (e202114070), Cheng-Yong Su et al. report the generation of dynamic nanospaces in solution by cationic cages as a catalytic platform for C(sp)−H activation.

Graphical Abstract

Free Access

Graphical Abstract: Angew. Chem. Int. Ed. 5/2022

  • First Published: 18 January 2022

Introducing …

Free Access

Christine Beemelmanns

  • First Published: 29 November 2021
Christine Beemelmanns

My biggest motivation is to accomplish and create something that makes a difference … My motto is that new findings always pave the way to new intriguing research questions, and that Mother Nature might have already invented it …” Find out more about Christine Beemelmanns in her Introducing … Profile.

Free Access

Jiannan Zhao

  • First Published: 10 December 2021
Jiannan Zhao

I am waiting for the day when someone will discover the origin of homochirality in nature … A key experience in my education was a trip to Germany and attending the 65th Lindau Nobel Laureates Meeting with ambitious young scientists from all natural science disciplines…” Find out more about Jiannan Zhao in his Introducing … Profile.

Meeting Review

Organic Chemistry

Plugging the Leak: Empowering Women in Organic Chemistry

  • First Published: 20 December 2021

Held June 24–25, 2021, the third annual Empowering Women in Organic Chemistry (EWOC) conference gathered organic chemists at all stages of the career pipeline for rich professional development opportunities and a showcase of recent scientific achievements. This Meeting Review outlines the program.

Minireviews

Metals in Medicine

Clinical Development of Metal Complexes as Photosensitizers for Photodynamic Therapy of Cancer

  • First Published: 08 November 2021
Clinical Development of Metal Complexes as Photosensitizers for Photodynamic Therapy of Cancer

Photodynamic therapy has complemented traditional cancer treatment modalities. Despite its success, the clinically applied photosensitizers are not ideal. To overcome their limitations increasing research efforts have been devoted towards the incorporation of a metal ion. In this Minireview, the clinical status of metal-containing compounds as photosensitizers for photodynamic therapy is reviewed.

Reviews

Homogeneous Catalysis

Open Access

Metathesis by Partner Interchange in σ-Bond Ligands: Expanding Applications of the σ-CAM Mechanism

  • First Published: 25 October 2021
Metathesis by Partner Interchange in σ-Bond Ligands: Expanding Applications of the σ-CAM Mechanism

This review highlights advances in the characterization and dynamic rearrangements of σ-bond complexes, most notably alkane and zincane complexes, but also different geometries of silane and borane complexes. We set out a selection of catalytic and stoichiometric examples of the σ-complex assisted metathesis mechanism that are supported by strong experimental and/or computational evidence.

Metal Halide Perovskites

Open Access

Atomic Level Insights into Metal Halide Perovskite Materials by Scanning Tunneling Microscopy and Spectroscopy

  • First Published: 13 October 2021
Atomic Level Insights into Metal Halide Perovskite Materials by Scanning Tunneling Microscopy and Spectroscopy

Scanning tunneling microscopy and spectroscopy are powerful techniques to visualize the topographic and electronic structures of metal halide perovskites with atomic-level resolution. These techniques can also be used to reveal the dynamics of surface defects and charge carriers as well as on-surface reactions and optoelectronic properties at the surface and interfaces of perovskite materials.

Communications

Sonodynamic Therapy | Hot Paper

Aggregation-Enhanced Sonodynamic Activity of Phthalocyanine–Artesunate Conjugates

  • First Published: 10 November 2021
Aggregation-Enhanced Sonodynamic Activity of Phthalocyanine–Artesunate Conjugates

An interesting aggregation-enhanced sonodynamic activity (AESA) effect was first observed based on the studies of phthalocyanine–artesunate conjugates and common organic sonosensitizers, which arose from boosted ultrasonic cavitation caused by nanostructured aggregates. We believed that the AESA effect in this work could open up a new avenue for the development of efficient sonosensitizers.

Zeolites | Very Important Paper

Open Access

Unravelling Channel Structure–Diffusivity Relationships in Zeolite ZSM-5 at the Single-Molecule Level

  • First Published: 17 November 2021
Unravelling Channel Structure–Diffusivity Relationships in Zeolite ZSM-5 at the Single-Molecule Level

The microscopic channel structure–diffusivity relationships in zeolites were unraveled using a combination of single-molecule localization microscopy and uniformly oriented zeolite thin films. New insights into the mechanism of the enhanced diffusion in hierarchical zeolites were obtained.

Fluorescent Probes | Hot Paper

Rational Design of a Two-Photon Fluorescent Probe for Human Cytochrome P450 3A and the Visualization of Mechanism-Based Inactivation

  • First Published: 01 December 2021
Rational Design of a Two-Photon Fluorescent Probe for Human Cytochrome P450 3A and the Visualization of Mechanism-Based Inactivation

A two-photon fluorescent probe for CYP3A was developed using a rational design strategy that optimized the key binding domain of the fluorophore. The probe semi-quantitatively detects and images CYP3A activity in various living systems, thereby providing a high-throughput screening system facilitating the evaluation of MBI-associated hepatotoxicity by CYP3A.

Supramolecular Chemistry

Entropy Versus Enthalpy Controlled Temperature/Redox Dual-Triggered Cages for Selective Anion Encapsulation and Release

  • First Published: 18 November 2021
Entropy Versus Enthalpy Controlled Temperature/Redox Dual-Triggered Cages for Selective Anion Encapsulation and Release

Cage 1P, which selectively encapsulates BPh4 over a wide range of temperatures, can be quantitatively oxidized to cage 1PO with more negative enthalpy (Δ) and entropy (Δ) that releases the captured BPh4 anions at high temperature but strongly encapsulates BPh4 at low temperature.

CO2 Reduction

A Reconstructed Cu2P2O7 Catalyst for Selective CO2 Electroreduction to Multicarbon Products

  • First Published: 02 December 2021
A Reconstructed Cu2P2O7 Catalyst for Selective CO2 Electroreduction to Multicarbon Products

The electrochemical in situ reconstruction of Cu2P2O7 during CO2 electroreduction generates highly porous Cu with abundant defects and low-coordinated sites, which facilitate CO adsorption with bridge and atop configurations, thus resulting in a high-rate production of C2+ fuels and chemicals.

Fluorescent Probes | Very Important Paper

A Bright, Renal-Clearable NIR-II Brush Macromolecular Probe with Long Blood Circulation Time for Kidney Disease Bioimaging

  • First Published: 30 November 2021
A Bright, Renal-Clearable NIR-II Brush Macromolecular Probe with Long Blood Circulation Time for Kidney Disease Bioimaging

A series of bright NIR-II brush macromolecular fluorophores (FBP) with high renal-clearance efficiency and long-blood circulation time has been developed. These achieve real-time in vivo NIR-II imaging of renal ischemia-reperfusion injury, tumor passive targeted imaging and renal cell carcinoma active targeted imaging with higher signal-to-noise ratio and extended retention time.

Photoacoustic Imaging

Cathespin B-Initiated Cypate Nanoparticle Formation for Tumor Photoacoustic Imaging

  • First Published: 08 December 2021
Cathespin B-Initiated Cypate Nanoparticle Formation for Tumor Photoacoustic Imaging

A near-infrared photoacoustic (PA) probe Cypate-CBT was designed for specific imaging and real-time tracking of cathespin B (CTSB) activity in CTSB-overexpressing cells and tumors. After Cypate-CBT entered into CTSB-overexpressing cells, it underwent glutathione reduction and CTSB cleavage to generate cypate nanoparticles Cypate-CBT-NPs, which enhanced both the intensity and retention time of the PA signal in tumor sites.

Medicinal Chemistry

Potent and Selective RIPK1 Inhibitors Targeting Dual-Pockets for the Treatment of Systemic Inflammatory Response Syndrome and Sepsis

  • First Published: 01 December 2021
Potent and Selective RIPK1 Inhibitors Targeting Dual-Pockets for the Treatment of Systemic Inflammatory Response Syndrome and Sepsis

A series of highly potent dual-mode RIPK1 inhibitors occupying both the allosteric and the ATP binding pockets were developed, exemplified by compound 21 (ZB-R-55), which is about 10-fold more potent than GSK2982772, and exhibits excellent kinase selectivity, good oral pharmacokinetics and good therapeutic effects in the LPS-induced sepsis model.

Materials Science | Hot Paper

Orienting an Organic Semiconductor into DNA 3D Arrays by Covalent Bonds

  • First Published: 30 November 2021
Orienting an Organic Semiconductor into DNA 3D Arrays by Covalent Bonds

The orienting of an organic semiconductor, a heptamer of poly(p-phenylene vinylene) (HPV), into DNA 3D arrays was achieved by rational design. Addressed with covalent bonds in a DNA tensegrity triangle motif, the quasi-one-dimensional molecules were well-aligned inside the crystalline lattices, as indicated by polarized fluorescent emission. This experiment demonstrated a simple approach to constructing photonic crystals with DNA-templated band-gap materials.

CO2 Reduction | Hot Paper

Proton/Electron Donors Enhancing Electrocatalytic Activity of Supported Conjugated Microporous Polymers for CO2 Reduction

  • First Published: 01 December 2021
Proton/Electron Donors Enhancing Electrocatalytic Activity of Supported Conjugated Microporous Polymers for CO2 Reduction

Phthalocyanines are polymerized via a solid ionothermal Scholl reaction in the presence of carbon nanotubes, resulting in an ultrathin conjugated microporous polymer sheath containing single-atom CoN4 as catalytic sites and H2Pc units as proton/electron donors, both of which interplay to enhance the electrocatalytic reduction of CO2 to CO.

Circularly Polarized Luminescence | Hot Paper

Modulating the Excited State Chirality of Dynamic Chemical Reactions in Chiral Micelles

  • First Published: 08 December 2021
Modulating the Excited State Chirality of Dynamic Chemical Reactions in Chiral Micelles

A hydrophobic cavity of chiral spherical micelles was used as the chiral space to encapsulate hydrophobic emitters and endow them with circularly polarized luminescence (CPL) properties in the aqueous phase. Particularly, through breaking the “C=N” bonds of Nile Red molecules, we have observed white CPL emission.

Transition-Metal Catalysis

Catalysis-Enabled Concise and Stereoselective Total Synthesis of the Tricyclic Prostaglandin D2 Metabolite Methyl Ester

  • First Published: 06 December 2021
Catalysis-Enabled Concise and Stereoselective Total Synthesis of the Tricyclic Prostaglandin D2 Metabolite Methyl Ester

The clinically important tricyclic prostaglandin D2 metabolite (PGDM) methyl ester was synthesized in eight steps from a readily available known compound. The synthesis features Z-selective cross-metathesis to form the challenging Z β,γ-unsaturated ester, palladium-catalyzed carbonylative spirolactonization to build the oxaspirolactone moiety, and nickel-catalyzed Ueno–Stork-type dicarbofunctionalization to form two key C−C bonds and stereocenters.

Protein Engineering | Hot Paper

Open Access

Sortase-Mediated Multi-Fragment Assemblies by Ligation Site Switching

  • First Published: 04 November 2021
Sortase-Mediated Multi-Fragment Assemblies by Ligation Site Switching

Sortase-mediated ligation (SML) of multiple peptide fragments is enabled by ligation site switching. An active sorting motif installed by default into the ligation product is switched from an active to an inactive state while a latent nucleophile in the ligation product is activated for SML. Repetitive cycles of SML and ligation site switching allow the assembly of multiple fragments with wild type sortase.

Medicinal Chemistry

Open Access

Substrate-Inspired Fragment Merging and Growing Affords Efficacious LasB Inhibitors

  • First Published: 11 November 2021
Substrate-Inspired Fragment Merging and Growing Affords Efficacious LasB Inhibitors

An efficient fragment merging and growing strategy with simple chemistry yielded a fragment-like inhibitor of the virulence factor LasB from Pseudomonas aeruginosa with a twelve-fold boost in activity. Our optimized structure shows an improved in vivo efficacy demonstrating the significance of exploiting alternative binding modes to succeed in simple fragment merging. The graphic was created with the software tool BioRender (www.biorender.com).

Surface Chemistry

Open Access

Exploiting Cooperative Catalysis for the On-Surface Synthesis of Linear Heteroaromatic Polymers via Selective C–H Activation

  • First Published: 17 November 2021
Exploiting Cooperative Catalysis for the On-Surface Synthesis of Linear Heteroaromatic Polymers via Selective C–H Activation

The cooperative catalytic role of sodium and silver adatoms in steering the on-surface polymerization of hexaazatriphenylene molecules on Ag(111) is demonstrated. By combining high-resolution scanning probe microscopy with density functional calculations, we elucidate how complex surface processes can be enabled by addition of atomic species designed for catalyzing specific reaction steps.

Research Articles

Supramolecular Catalysis | Hot Paper

Creating Dynamic Nanospaces in Solution by Cationic Cages as Multirole Catalytic Platform for Unconventional C(sp)−H Activation Beyond Enzyme Mimics

  • First Published: 15 November 2021
Creating Dynamic Nanospaces in Solution by Cationic Cages as Multirole Catalytic Platform for Unconventional C(sp)−H Activation Beyond Enzyme Mimics

The generation of permeable porous-cage nanospaces in solution by a highly charged cationic [Pd6(RuL3)8]28+ cage for multirole and multi-way supramolecular catalysis is reported.

Peptides | Hot Paper

Open Access

Binding of Natural Peptide Ligands to the Neuropeptide Y5 Receptor

  • First Published: 25 November 2021
Binding of Natural Peptide Ligands to the Neuropeptide Y5 Receptor

Complementary biochemical methods and molecular modeling reveal how NPY and its natural analogues bind to the Y5 GPCR, filling in the gap in the knowledge of the Y multiligand/multireceptor system. This provides the first base for the rational design of selective Y5R ligands with therapeutic potential.

Photodynamic Inactivation

Design of a Metallacycle-Based Supramolecular Photosensitizer for In Vivo Image-Guided Photodynamic Inactivation of Bacteria

  • First Published: 21 November 2021
Design of a Metallacycle-Based Supramolecular Photosensitizer for In Vivo Image-Guided Photodynamic Inactivation of Bacteria

A metallacycle-based supramolecular photosensitizer (1⊃2) for in vivo image-guided photodynamic inactivation of bacteria is reported. Through host-guest interaction, the assembly 1⊃2, with improved fluorescence signals and ROS production capabilities, is employed for in vivo fluorescence tracking as well as accurate image-guided treatment of S. aureus infection without noticeable side effects.

Photocatalysis

Open Access

Photophysics of Perylene Diimide Dianions and Their Application in Photoredox Catalysis

  • First Published: 17 November 2021
Photophysics of Perylene Diimide Dianions and Their Application in Photoredox Catalysis

The two-electron reduced, luminescent forms of perylene diimides can be employed for thermodynamically challenging photoredox reactions in aqueous and in organic solution.

Artificial Metalloenzymes

Directed Evolution of Artificial Metalloenzymes in Whole Cells

  • First Published: 11 November 2021
Directed Evolution of Artificial Metalloenzymes in Whole Cells

Whole-cell E. coli platform enables directed evolution campaigns with ArMs containing an abiotic Ir-porphyrin cofactor involving the generation of more than 4000 mutants to develop an enantioselective insertion of a simple acyclic carbene from a diazo ester into the N−H bond of N-methyl aniline that has formed product with poor enantioselectivity when catalyzed by prior enzyme systems.

Zeolites | Hot Paper

Enhanced Reactivity of Accessible Protons in Sodalite Cages of Faujasite Zeolite

  • First Published: 12 November 2021
Enhanced Reactivity of Accessible Protons in Sodalite Cages of Faujasite Zeolite

Faujasite (FAU) zeolites (with Si/Al ratio of ca. 1.7) undergo mild dealumination at moderate ion exchange conditions (0.01 to 0.6 M of NH4NO3 solutions) resulting in protons circumscribed by sodalite cages becoming accessible for reaction. The ratio of protons in sodalite cages (HSOD) to supercages (HSUP) can be manipulated by adjusting ammonium concentrations used in ion exchange.

Peptides

Site-Selective Itaconation of Complex Peptides by Photoredox Catalysis

  • First Published: 29 November 2021
Site-Selective Itaconation of Complex Peptides by Photoredox Catalysis

Photoredox catalysis has emerged as a powerful approach for site-selective peptide functionalization. Herein, we report a highly N-termini-specific method to rapidly access itaconated peptide derivatives under mild photoredox conditions. Distinct from conventional methods that rely on residue nucleophilicity, this method proceeds through a highly reactive carbamoyl radical intermediate to achieve excellent selectivity. Itaconated peptides can be further functionalized to access peptide-protein conjugates.

Synthetic Methods | Hot Paper

Trifluoroethanol as a Unique Additive for the Chemoselective Electrooxidation of Enamines to Access Unsymmetrically Substituted NH-Pyrroles

  • First Published: 01 December 2021
Trifluoroethanol as a Unique Additive for the Chemoselective Electrooxidation of Enamines to Access Unsymmetrically Substituted NH-Pyrroles

A chemoselective electrooxidative heterocoupling of two different enamines is reported for the synthesis of unsymmetrically substituted NH-pyrroles. A “magic effect” of the additive trifluoroethanol is utilized to achieve the desired chemoselectivity by tuning the oxidation potentials and controlling the activation energy of the rate-determining step.

Transition Metal Complexes | Hot Paper

Bimetallic Copper/Ruthenium/Osmium Complexes: Observation of Conformational Differences Between the Solution Phase and Solid State by Atomic Pair Distribution Function Analysis

  • First Published: 17 November 2021
Bimetallic Copper/Ruthenium/Osmium Complexes: Observation of Conformational Differences Between the Solution Phase and Solid State by Atomic Pair Distribution Function Analysis

The solution phase structure of five bimetallic CuI/RuII/OsII complexes was revealed by high-energy X-ray scattering and pair distribution function analysis (HEXS/PDF). Assisted by computational simulation, conformational differences of the complexes in the solution and solid states were identified with sub-Ångström resolution.

Bioconjugation

Tunable Amine-Reactive Electrophiles for Selective Profiling of Lysine

  • First Published: 11 November 2021
Tunable Amine-Reactive Electrophiles for Selective Profiling of Lysine

Tunable and hydrolytically stable electrophiles are reported for the chemo-selective labeling of lysine with mass sensitive probes. These tunable amine-reactive electrophiles (TAREs) were used to label proteins in various subcellular compartments inside cells and for global identification of lysine in the human proteome.

Isotope Labelling | Hot Paper

Open Access

Stable Isotope Phosphate Labelling of Diverse Metabolites is Enabled by a Family of 18O-Phosphoramidites

  • First Published: 03 November 2021
Stable Isotope Phosphate Labelling of Diverse Metabolites is Enabled by a Family of 18O-Phosphoramidites**

A family of 18O2-phosphoramidites facilitates synthetic access on gram-scale to various isotopically pure 18O-labelled phosphate products, like nucleotides, inositol phosphates, polyphosphates, and DNA. The utility of these 18O-natural products is underlined in the assignment of various metabolites from biological matrices using capillary electrophoresis electrospray ionisation triple quadrupole mass spectrometry.

Natural Products

Open Access

A Modular Approach to the Antifungal Sphingofungin Family: Concise Total Synthesis of Sphingofungin A and C

  • First Published: 22 October 2021
A Modular Approach to the Antifungal Sphingofungin Family: Concise Total Synthesis of Sphingofungin A and C

A short and flexible total synthesis of antifungal and antiparasitic sphingofungins A–D and congeners was developed by combining a versatile decarboxylative coupling reaction and a cross metathesis protocol.

Photochemistry | Hot Paper

Generation of Oxyphosphonium Ions by Photoredox/Cobaloxime Catalysis for Scalable Amide and Peptide Synthesis in Batch and Continuous-Flow

  • First Published: 15 November 2021
Generation of Oxyphosphonium Ions by Photoredox/Cobaloxime Catalysis for Scalable Amide and Peptide Synthesis in Batch and Continuous-Flow

A photocatalytic method for the synthesis of amides and peptides is reported. Synergistic cooperation between a cobaloxime and a photoredox catalyst removes the elements of H2O through the use of PPh3 as a gentle organic reductant. The deoxygenative method is compatible with gram-scale peptide synthesis and applicable to peptide fragment condensation and SPPS, which may find applications in both organic synthesis and pharmaceutical production.

Capacitance

Open Access

Unexpectedly High Capacitance of the Metal Nanoparticle/Water Interface: Molecular-Level Insights into the Electrical Double Layer

  • First Published: 18 November 2021
Unexpectedly High Capacitance of the Metal Nanoparticle/Water Interface: Molecular-Level Insights into the Electrical Double Layer

Nano-impact electrochemistry revealed an anomalously high capacitance for Pt nanoparticles and to a lower extent for Au nanoparticles at potentials more negative than their potential of zero charge. MD calculations showed that the strong interaction of metal with water molecules leads to water chemisorption and accumulation of ions in the Helmholtz layer beyond expectation, resulting in a higher interface charge storage ability.

Hot Electrons

In Situ Raman Probing of Hot-Electron Transfer at Gold–Graphene Interfaces with Atomic Layer Accuracy

  • First Published: 22 November 2021
In Situ Raman Probing of Hot-Electron Transfer at Gold–Graphene Interfaces with Atomic Layer Accuracy

Hot-electron transfer at Au–graphene interfaces has been investigated in situ with atomic layer accuracy, and it is shown that hot electrons can be injected from plasmonic Au nanoparticles to graphene and penetrate up to four layers of graphene.

Polyoxometalate Electrocatalysts

Molecular Transition Metal Oxide Electrocatalysts for the Reversible Carbon Dioxide–Carbon Monoxide Transformation

  • First Published: 29 November 2021
Molecular Transition Metal Oxide Electrocatalysts for the Reversible Carbon Dioxide–Carbon Monoxide Transformation

A modular synthesis of trimetallo-substituted polyanions enables the preparation of designer catalysts. Here this approach was used to prepare electrocatalysts for the selective reduction of CO2 to CO using a tri-copper-substituted polyanion. In contrast, Fe–Ni-substituted polyanions preferably catalyzed the oxidation of CO to CO2, showing a reactivity profile reminiscent of the reactivity of Fe–Ni-based carbon monoxide dehydrogenase enzymes.

Zeolites | Hot Paper

Zinc Containing Small-Pore Zeolites for Capture of Low Concentration Carbon Dioxide

  • First Published: 19 November 2021
Zinc Containing Small-Pore Zeolites for Capture of Low Concentration Carbon Dioxide

Low concentration CO2 is adsorbed in zinc containing CHA-type zeolites with a high capacity of 0.67 mmol CO2/g-zeolite. The materials exhibit higher CO2 capacity, faster kinetics, lower desorption energy than low-silica 13X zeolites. Zeolite framework and the states and locations of zinc ions play crucial roles in the adsorption performance.

Medical Imaging

Open Access

A Bivalent Activatable Fluorescent Probe for Screening and Intravital Imaging of Chemotherapy-Induced Cancer Cell Death

  • First Published: 11 November 2021
A Bivalent Activatable Fluorescent Probe for Screening and Intravital Imaging of Chemotherapy-Induced Cancer Cell Death

We describe Apotracker Red as a single fluorescent activatable probe for robust quantification of cancer cell death in fluorescence-based assays and in vivo using multiphoton intravital imaging in mouse models of breast cancer.

Lewis Pairs

Linear Extension of Anthracene via B←N Lewis Pair Formation: Effects on Optoelectronic Properties and Singlet O2 Sensitization

  • First Published: 30 November 2021
Linear Extension of Anthracene via B←N Lewis Pair Formation: Effects on Optoelectronic Properties and Singlet O2 Sensitization

Linearly B←N Lewis pair extended anthracenes are prepared by highly regioselective N-directed electrophilic borylation. Their LUMOs are higher in energy and their HOMO–LUMO gaps are significantly larger compared to those of the respective laterally functionalized species. Photooxygenation studies reveal effective singlet oxygen sensitization with a largely reduced tendency for self-sensitized endoperoxide formation.

Perovskite Solar Cells

Open Access

Green-Chemistry-Inspired Synthesis of Cyclobutane-Based Hole-Selective Materials for Highly Efficient Perovskite Solar Cells and Modules

  • First Published: 16 December 2021
Green-Chemistry-Inspired Synthesis of Cyclobutane-Based Hole-Selective Materials for Highly Efficient Perovskite Solar Cells and Modules

A molecularly engineered cyclobutane-based hole-transporting material synthesised using simple and green-chemistry-inspired protocols achieves an impressive efficiency of 21 % in perovskite solar cells and over 19 % in perovskite solar module with an active area of 30.24 cm2.

Host–Guest Chemistry

A Conjugated Figure-of-Eight Oligoparaphenylene Nanohoop with Adaptive Cavities Derived from Cyclooctatetrathiophene Core

  • First Published: 24 November 2021
A Conjugated Figure-of-Eight Oligoparaphenylene Nanohoop with Adaptive Cavities Derived from Cyclooctatetrathiophene Core

Based on strained oligoparaphenylene loops and a flexible cyclooctatetrathiophene moiety, a fully conjugated bis-macrocycle is efficiently constructed, and possesses rigid and guest-adaptive cavities. Its peanut-like 1:2 host–guest complexes with C60 or C70 have been isolated and characterized, respectively.

Nanostructures

Open Access

Control over Multiple Nano- and Secondary Structures in Peptide Self-Assembly

  • First Published: 10 November 2021
Control over Multiple Nano- and Secondary Structures in Peptide Self-Assembly

We describe the nanostructural and conformational versatility of the biologically active peptide PEP-1, which self-assembles into up to six different aggregate morphologies and forms up to four different secondary structures in a controlled manner depending on pH, concentration, and temperature.

On-Surface Synthesis | Hot Paper

Abiotic Formation of an Amide Bond via Surface-Supported Direct Carboxyl–Amine Coupling

  • First Published: 28 October 2021
Abiotic Formation of an Amide Bond via Surface-Supported Direct Carboxyl–Amine Coupling

Combined scanning tunneling microscopy and X-ray photoelectron spectroscopy studies provide evidence for thermally activated abiotic formation of amide bonds between adsorbed precursors through direct carboxyl–amine coupling under ultrahigh-vacuum conditions by means of on-surface synthesis.

Hydrogenation | Very Important Paper

Local Environment Determined Reactant Adsorption Configuration for Enhanced Electrocatalytic Acetone Hydrogenation to Propane

  • First Published: 25 November 2021
Local Environment Determined Reactant Adsorption Configuration for Enhanced Electrocatalytic Acetone Hydrogenation to Propane

For acetone to propane electrohydrogenation, we unveiled how the local environmental pH determines the adsorption configuration of acetone, and further, the efficiency of the catalytic process. Moreover, it is shown that the reaction efficiency of the reaction can be improved by simply adjusting local pH instead of complex catalyst engineering.

Supramolecular Polymers

Open Access

Biasing the Hierarchy Motifs of Nanotoroids: from 1D Nanotubes to 2D Porous Networks

  • First Published: 25 November 2021
Biasing the Hierarchy Motifs of Nanotoroids: from 1D Nanotubes to 2D Porous Networks

The steric demand exerted by the peripheral side chains of the reported azobenzene dyads impedes their hierarchical self-assembly from nanotoroids into nanotubes. In contrast, they organize into 2D porous networks on substrate upon solution processing. Photoisomerization of azobenzene moieties allows efficient dissociation/reorganization of nanotoroids in solution, demonstrating their potential as photoresponsive 2D porous nanosheets.

Solar Cells | Hot Paper

Diammonium Molecular Configuration-Induced Regulation of Crystal Orientation and Carrier Dynamics for Highly Efficient and Stable 2D/3D Perovskite Solar Cells

  • First Published: 23 November 2021
Diammonium Molecular Configuration-Induced Regulation of Crystal Orientation and Carrier Dynamics for Highly Efficient and Stable 2D/3D Perovskite Solar Cells

Various diammonium spacer cations are used to construct 2D/3D perovskite. The mechanism of molecular configuration-induced regulation of crystal orientation and carrier dynamics is investigated. 2D/3D perovskite solar cells based on 2,2′-(ethylenedioxy)bis(ethylamine) achieve a device efficiency of 22.68 % and excellent moisture stability, retaining 82 % of initial efficiency after aging at 50±5 % relative humidity for 1560 h.

CO2 Reduction | Hot Paper

Imparting CO2 Electroreduction Auxiliary for Integrated Morphology Tuning and Performance Boosting in a Porphyrin-based Covalent Organic Framework

  • First Published: 21 November 2021
Imparting CO2 Electroreduction Auxiliary for Integrated Morphology Tuning and Performance Boosting in a Porphyrin-based Covalent Organic Framework

A kind of functionalizing exfoliation agent has been selected to simultaneously modify and exfoliate bulk COFs into functional nanosheets and the obtained materials can be applied in highly selective CO2 electroreduction into CH4.

Hemilabile Ligands | Hot Paper

Controlling Oxidative Addition and Reductive Elimination at Tin(I) via Hemi-Lability

  • First Published: 22 November 2021
Controlling Oxidative Addition and Reductive Elimination at Tin(I) via Hemi-Lability

A distannyne supported by a pincer ligand featuring pendant CH2NiPr2 arms is capable of reversibly activating E−H bonds at one or both of the tin centres through dissociation of the hemi-labile N–Sn donor/acceptor interactions. This chemistry can be exploited to sequentially (and reversibly) assemble mixed-valence chains of tin atoms of the type ArSn{Sn(Ar)H}nSnAr (n=1,2).

Polymerization | Very Important Paper

From Impossible to Possible: Atom-Economic Polymerization of Low Strain Five-Membered Carbonates

  • First Published: 01 December 2021
From Impossible to Possible: Atom-Economic Polymerization of Low Strain Five-Membered Carbonates

An atom-economic polymerization of five-membered propylene carbonate (PC) for preparation of polyester and polycarbonate simultaneously is reported. The key premise of our strategy is the careful elaboration of the mechanism of direct ring-opening polymerization of PC, which emphasizes the importance of the in situ released propylene oxide.

Block Copolymers | Hot Paper

Janus Photonic Microspheres with Bridged Lamellar Structures via Droplet-Confined Block Copolymer Co-Assembly

  • First Published: 02 December 2021
Janus Photonic Microspheres with Bridged Lamellar Structures via Droplet-Confined Block Copolymer Co-Assembly

A new complex photonic structure, bridged lamellae, with intriguing color reflections is successfully fabricated through well-controlled co-assembly of lipophilic and amphiphilic bottlebrush block copolymers within shrinking droplets. Self-assembled Janus microspheres with precisely tunable dual light reflections are facilely obtained through the manipulation of the co-assembly at a molecular level.

Polymer Calibration

Solvent-Independent Molecular Weight Determination of Polymers Based on a Truly Universal Calibration

  • First Published: 03 December 2021
Solvent-Independent Molecular Weight Determination of Polymers Based on a Truly Universal Calibration

A universal calibration curve for molecular weight determination is presented. Diffusion coefficients of poly(styrene) and poly(ethylene glycol) standards are measured via diffusion-ordered NMR spectroscopy. These diffusion/molecular weight relationships are calibrated to be solvent-independent. This universal calibration creates a novel platform wherein molecular weights of unknown polymers can be found using the universal calibration curve independent of what solvent is used.

Covalent Organic Frameworks

Open Access

A Nanographene-Based Two-Dimensional Covalent Organic Framework as a Stable and Efficient Photocatalyst

  • First Published: 06 December 2021
A Nanographene-Based Two-Dimensional Covalent Organic Framework as a Stable and Efficient Photocatalyst

Dibenzo[hi,st]ovalene-based covalent organic frameworks form 2D ABC stacking sp2 carbon lattices with robust olefin linkage. The resulting 2D unique structure exhibits high photoconductivity, charge-carrier mobility and photocatalytic activity in hydroxylation attributed to the narrow-energy-gap nanographene cores as active sites.

Synthetic Methods

Dynamic Kinetic Sensitization of β-Dicarbonyl Compounds—Access to Medium-Sized Rings by De Mayo-Type Ring Expansion

  • First Published: 24 November 2021
Dynamic Kinetic Sensitization of β-Dicarbonyl Compounds—Access to Medium-Sized Rings by De Mayo-Type Ring Expansion

A photocatalyzed ring expansion procedure for a two-carbon homologation of cyclic carbonyl compounds, towards medium-sized ring systems, is introduced. Key to success is the catalyst fac-[Ir(CF3-pmb)3] (ET=73.3 kcal mol−1), which allows for selective activation of the substoichiometric enol species. The mechanism has been corroborated by time-resolved spectroscopy and enabled a full kinetic analysis of the dynamic kinetic sensitization scenario.

Small Molecule Activation | Hot Paper

Open Access

Synthesis and Reactivity of a Neutral Homocyclic Silylene

  • First Published: 19 November 2021
Synthesis and Reactivity of a Neutral Homocyclic Silylene

The neutral homocyclic silylene 2 was obtained from a bicyclic silicon(I) amide J. This reaction proceeds via the anionic homoaromatic ring compound 1. The two-coordinate Si-atom in 1 is stabilized via a 3-center 2-electron π-bond and that in 2 via an allyl-type π-electron delocalization. Compound 2 undergoes cycloadditions with alkenes and alkynes and oxidative addition with methanol. The reaction with ethylene yields a tricyclic ring species.