Tetrasubstituted α‐amino allenoates were generated by a chiral phosphoric acid catalyzed dearomative γ‐addition of 2,3‐disubstituted indoles to β,γ‐alkynyl‐α‐imino esters. This method provides access to a series of highly functionalized tetrasubstituted allenes featuring quaternary stereocenters with excellent regio‐, diastereo‐, and enantioselectivities. Abstract The first asymmetric synthesis of tetrasubstituted α‐amino allenoates by a chiral phosphoric acid catalyzed dearomative γ‐addition...
Fri Nov 22, 2019 22:05
Makes sense: As two ligands offer more opportunity than one to tune MOF conductivity and topology, a 2D π‐conjugated copper‐based electronically conductive MOF with two different trigonal organic ligands was developed (see structure). The semiconductivity and high porosity of the resulting nanowires provided a low conductivity baseline and highly accessible surface areas, thus resulting in excellent room‐temperature chemiresistive sensing properties. Abstract Single‐ligand‐based electronically...
Fri Nov 22, 2019 22:05
A versatile supramolecular sensing platform based on the switching mechanism of a self‐aggregated coumarin‐quinazoline derivative was used to selectively detect parallel G‐quadruplex (G4) DNA structures both in vitro and in cells. The programmed reorganization of tightly packed chromophores was further used to build up a programmable label‐free molecular logic system. Abstract The design of turn‐on dyes with optical signals sensitive to the formation of supramolecular structures provides fascinating...
Fri Nov 22, 2019 22:05
Sharp as a needle: Reported here is the first aqueous ring‐opening polymerization (ROP) of carboxyanhydrides (NCAs) using α‐amino‐poly(ethylene oxide) as the macroinitiator to protect NCA monomers from hydrolysis through spontaneous in situ self‐assembly (ISA). This ROPISA process affords well‐defined amphiphilic diblock copolymers that simultaneously form needle‐like nanoparticles. Abstract Reported here is the first aqueous ring‐opening polymerization (ROP) of N‐carboxyanhydrides (NCAs) using...
Fri Nov 22, 2019 22:05
An NHC‐ligated 3‐benzoborepin with a bridged structure is transformed to an NHC‐ligated boranorcaradiene by a thermal 6π‐electrocyclic reaction followed by a 1,5‐boron shift with stereoinversion at boron. DFT calculations support the reaction mechanism, stereoselectivity, and the unusual thermodynamic stability of both intermediary and isolated NHC‐boranorcaradienes. (NHC= N‐heterocyclic carbene). Abstract An N‐heterocyclic‐carbene‐ligated 3‐benzoborepin with a bridged structure has been synthesized...
Fri Nov 22, 2019 22:00
We report herein the first examples of palladium‐catalyzed enantioselective Cacchi reaction for the synthesis of indoles bearing a chiral C2‐aryl axis. In the presence of a catalytic amount of Pd(OAc)2 and (R,R)‐QuinoxP* ligand, reaction of N‐aryl(alkyl)sulfonyl‐2‐alkynylanilides with arylboronic acids under oxygen atmosphere afforded enantioenriched 2,3‐disubstituted indoles in high yields and enantioselectivities. The indole ring was de novo constructed in this process and a complexation‐induced...
Fri Nov 22, 2019 19:00
Pathogenesis hallmarks for tuberculosis (TB) are the mycobacterium tuberculosis (Mtb) escape from phagolysosomal destruction and limited drug delivery into host cells. Several nanomaterials can entrap into lysosomes, but how to develop functional nanomaterials to promote phagolysosomal Mtb clearance remains a big challenge. Here, we first reported the bactericidal effects of selenium nanoparticles (Se NPs) against Mtb and further introduced a novel nanomaterial‐assisted anti‐TB strategy manipulating...
Fri Nov 22, 2019 18:59
Secondary lithium metal batteries afford great promises for future energy storage applications. However, high‐energy‐density Li metal batteries suffer from short lifespan under practical conditions including limited lithium, high cathode loading, and lean electrolyte due to the absence of appropriate solid electrolyte interphase (SEI). Herein, a sustainable SEI was designed rationally by combining fluorinated co‐solvents with sustained‐release additives in response to challenges from practical conditions....
Fri Nov 22, 2019 15:53
Azacycles such as indoles and tetrahydroquinolines are privileged structures in drug development. Efficient strategies for the diverse synthesis of azacycles are highly sought after. Here, we report on an unprecedented regiodivergent intramolecular nucleophilic addition reaction of imines as a flexible approach to access N‐functionalized indoles or tetrahydroquinolines, by the control of reaction at the N‐terminus or C‐terminus. Using ketimines derived from 2‐(2‐nitroethyl)anilines with isatins or...
Fri Nov 22, 2019 15:29
A supramolecular assembly of single‐chain magnets (SCM) is reported that self‐organize to form chiral supramolecular nanotubes where their magnetic behavior is preserved. Magnetic relaxation with both finite and infinite‐size regimes is observed and confirms the validity of the Ising approximation. Abstract We report a single‐chain magnet (SCM) made of a terbium(III) building block and a nitronyl‐nitroxide radical (NIT) functionalized with an aliphatic chain. This substitution is targeted to...
Fri Nov 22, 2019 14:33
Unactivated aryl fluorides engage in SNAr reactions at room temperature and without the strong base using DDQ as an electrophotocatalyst. Abstract The electrophotocatalytic SNAr reaction of unactivated aryl fluorides at ambient temperature without strong base is demonstrated.
Fri Nov 22, 2019 14:32
Of the Li metal batteries, the Li–O2 battery has the highest theoretical specific energy. In their Communication (DOI: https://doi.org/10.1002/anie.20191042710.1002/anie.201910427), Y.‐Y. Sun, T Zhang, and co‐workers find that the synergic effect of the strong binding of RuO2 to I2 and the strong solvation effect of DMSO on I2 could shift the direction of the well‐known reaction I− + I2⇄I3− to the left‐hand side. A Li–O2 battery with the Li/DMSO+LiI/RuO2 structure shows significantly enhanced stability...
Fri Nov 22, 2019 14:31
A new image: A benzothiadiazole‐based covalent organic framework is reported to promote two‐photon induction and overcome the aggregation‐caused emission quenching of the chromophores. The design improves upon current near‐infrared two‐photon induced fluorescence imaging techniques. Abstract Fluorescent materials exhibiting two‐photon induction (TPI) are used for nonlinear optics, bioimaging, and phototherapy. Polymerizations of molecular chromophores to form π‐conjugated structures were hindered...
Fri Nov 22, 2019 14:31
Duchenne muscular dystrophy (DMD) is a fatal muscle‐wasting disease arising from mutations in the dystrophin gene. Upregulation of utrophin to compensate for the missing dystrophin offers a potential therapy independent of patient genotype. The first‐in‐class utrophin modulator ezutromid/SMT C1100 was developed from a phenotypic screen through to a Phase 2 clinical trial. Promising efficacy and evidence of target engagement was observed in DMD patients after 24 weeks of treatment, however trial endpoints...
Fri Nov 22, 2019 14:30
Artificial humic acids made from biomass in a hydrothermal process are a practical route to solubilize otherwise insoluble phosphorous species, as shown by F. Yang, M. Antonietti et al. in their Communication (DOI: https://doi.org/10.1002/anie.20191106010.1002/anie.201911060). The picture recalls a famous Chinese artpiece, “The man who broke the mountains”. It symbolizes in this context the crushing of phosphate rock to nutriate the flowers shown on the right side of the picture. The man represents...
Fri Nov 22, 2019 14:30
Thermoelectric conversion is made possible by exploiting selenium substitution along with side chain modifications, which is a powerful strategy for designing high‐mobility organic semiconductors. In their Research Article (DOI: https://doi.org/10.1002/anie.20191105810.1002/anie.201911058), C.‐a. Di, D. Zhang et al. demonstrate that selenium‐substituted diketopyrrolopyrrole derivatives can exhibit state of the art thermoelectric performance, which provides a novel way towards rationally designed...
Fri Nov 22, 2019 14:28
We have developed photo‐caged antibody fragments that are impaired in their antigen binding capacity and can be activated by irradiation with UV light (365 nm). Our rational design concept builds on the selective photo‐caging of a single residue in a central position of the antibody’s paratope region. We selected tyrosine residues because of their frequent occurrence in the complementarity determining regions (CDRs) and incorporated o‐nitrobenzyl‐protected tyrosine variants using the genetic code...
Fri Nov 22, 2019 11:55
Starting from diverse alkene‐tethered aryl iodides and O‐benzoyl‐hydroxylamines, the enantioselective reductive cross‐electrophilic 1,2‐carboamination of unactivated alkenes was achieved using a chiral pyrox−nickel complex as the catalyst. This mild, modular, and practical protocol provides rapid access to a variety of β‐chiral amines with an enantioenriched aryl‐substituted quaternary carbon center in good yield and with excellent enantioselectivity. This process reveals a complementary regioselectivity...
Fri Nov 22, 2019 11:30
Electronic building blocks: 1,3‐Indandione‐terminated quinoids with various termini and central cores were synthesized by an alkoxide‐mediated rearrangement reaction. Their properties can be regulated by tuning the central cores and the aryl termini. These compounds display unipolar n‐type semiconductor characteristics with electron mobilities of up to 0.38 cm2 V−1 s−1. Abstract A series of 1,3‐indandione‐terminated π‐conjugated quinoids were synthesized by alkoxide‐mediated rearrangement reaction...
Fri Nov 22, 2019 11:03
The progress in nanomedicine (NM) using nanoparticles (NPs) is mainly based on drug carriers for the delivery of classical chemotherapeutics. While low NM delivery rates limit therapeutic efficacy, an entirely different approach was investigated. A homologous series of engineered CuO NPs was designed for dual purpose (carrier and drug) with a direct chemical composition‐biological functionality relationship. Model‐based dissolution kinetics (initial burst‐like followed by a solid state diffusion...
Fri Nov 22, 2019 11:03
The Sonogashira‐type cross‐coupling reaction is one of the most significant alkynylation transformations in organic chemistry. The first palladium‐catalyzed intramolecular Heck/Sonogashira reaction of alkenes with terminal alkynes was realized. With this method, a variety of unique substituted chiral benzene‐fused cyclic skeletons bearing an alkynyl all‐carbon quaternary stereocenter were facilely accessed in a straightforward, high‐yielding, and highly stereoselective manner under mild conditions....
Thu Nov 21, 2019 21:59
Herein is described an Ir(III) porphyrin‐catalyzed intermolecular C(sp³)–H insertion reaction of quinoid carbene (QC). The reaction was designed by harnessing the hydrogen atom transfer (HAT) reactivity of metal‐QC species with aliphatic substrates followed by a radical rebound process to afford C–H arylation products. This methodology is efficient for the arylation of activated hydrocarbons such as 1,4‐cyclohexadienes (down to 40 min reaction time, up to 99% yield, up to 1.0...
Thu Nov 21, 2019 20:24
Organic‐inorganic hybrid cathode materials have advantages of both components. Herein, we report an attractive diphenyl trisulfide‐selenium nanowire (DPTS‐Se) hybrid cathode material for rechargeable lithium batteries. During discharge, three voltage plateaus associated with three lithiation processes are observed. During recharge, the combination of the radicals formed upon delithiation leads to several new phenyl sulfoselenide compounds which are confirmed by HPLC‐QTof‐MS. The formation of S‐Se...
Thu Nov 21, 2019 18:59
Heterostructural metal/metal oxides are the very promising substituents of noble‐metal catalysts; however, generation and further stabilization of accessible metal/metal oxide heterojunctions are very difficult. Herein, a strategy to in situ encapsulate and stabilize Cu/Cu2O nanojunctions in porous organic frameworks is developed by tuning the acrylate contents in copper‐based metal‐organic frameworks (Cu‐MOFs) and the pyrolytic conditions. The acrylate groups play important roles on improving the...
Thu Nov 21, 2019 17:05
Palladium‐catalyzed asymmetric [4 + 3] cyclization of trimethylenemethane donors with benzofuran‐derived azadienes has been established, furnishing chiral benzofuro[3,2‐b]azepine frameworks in high yields (up to 98%) with exclusive regioselectivities and excellent stereoselectivities (up to >20:1 dr, >99% ee). This reaction represents the first catalytic asymmetric [4 + 3] cyclization of Pd‐trimethylenemethane (Pd‐TMM), which would enrich arsenal of Pd‐TMM chemistry in organic synthesis. In...
Thu Nov 21, 2019 17:00
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