A study in contrast: An optical probe with turn‐on chemiluminescence and NIR fluorescence in the presence of superoxide anion (O2.−) and N‐acetyl‐β‐d‐glucosaminidase (NAG), respectively, was synthesized. The probe enables real‐time in vivo imaging and early detection of contrast‐induced acute kidney injury. Abstract Despite its high morbidity and mortality, contrast‐induced acute kidney injury (CIAKI) remains a diagnostic dilemma because it relies on in vitro detection of insensitive late‐stage...
Thu Oct 24, 2019 14:35
Breaking the silence: A silent gene cluster was engaged by the expression of a positive regulator gene in tandem mode, directing the biosynthesis of eight aromatic polyketides. These polyketides comprise two different frameworks, two pentacyclic isomers (1 and 2) and six glycosylated tetracyclines (3–8), which are proposed to arise from divergent pathways originating from a common intermediate. Abstract One biosynthetic gene cluster (BGC) usually governs the biosynthesis of a series of compounds...
Thu Oct 24, 2019 14:34
Discovered by oxidant: A novel umpolung strategy for α‐functionalization of aldehydes with nucleophiles is presented. The strategy uses organocatalytic enamine activation and quinone‐promoted oxidation to access O‐bound quinol‐intermediates that undergo nucleophilic substitution reactions. Abstract Nucleophile–nucleophile coupling is a challenging transformation in organic chemistry. Herein we present a novel umpolung strategy for α‐functionalization of aldehydes with nucleophiles. The strategy...
Thu Oct 24, 2019 14:34
Jumping crystals: Multifunctional amphidynamic crystalline materials based on dumbbell shape gold(I) complexes are characterized by motion at the molecular and macroscopic scales. Macroscopic motion occurs in the form thermosalient crystal moving and/or jumping as the result of anisotropic thermal expansion. Phosphorescence of the crystals is correlated to the molecular rotation. Abstract Herein we report a crystalline molecular rotor with rotationally modulated triplet emission that displays...
Thu Oct 24, 2019 16:16
Thu Oct 24, 2019 14:31
Suck it up! An isolated monoalumoxane anion reacts with the greenhouse gases CO2 and N2O to generate potentially useful chemical compounds. Abstract The deoxygenative conversion of carbon dioxide to carbon monoxide is promoted by the aluminyl anion [Al(NONAr)]− (NONAr=[O(SiMe2NAr)2]2−, Ar=2,6‐iPr2C6H3). The reaction proceeds via the isolable monoalumoxane anion [Al(NONAr)(O)]−, containing a terminal aluminum‐oxygen bond. This species reacts with a second equivalent of carbon dioxide to afford...
Thu Oct 24, 2019 14:25
Spring loaded: A spring‐like highly oriented mesoporous graphitic carbon anode (OGCS) undergoes K‐adsorption in mesopores then K‐intercalation in the graphite layer to form KC8 with a low discharge voltage. It provides a large number of active edge‐plane sites and expands one‐dimensionally along the long axis, resulting in ultra‐high capacity and long‐term stability over 10 000 cycles. Abstract A highly oriented mesoporous graphitic carbon nanospring (OGCS) with graphitic layers that are perpendicular...
Thu Oct 24, 2019 14:23
We're jammin’: The formation, assembly, and jamming of a new type MXene‐based Janus‐like nanoparticle surfactants, termed MXene‐surfactants (MXSs), is reported through the cooperative assembly of MXene and amine‐functionalized polyhedral oligomeric silsesquioxane at the oil–water interface. The MXSs can significantly enhance the interfacial activity of MXene nanosheets. Abstract 2D transition metal carbides and nitrides (MXenes), a class of emerging nanomaterials with intriguing properties,...
Thu Oct 24, 2019 14:20
That simple: The enantioselective dearomatization of indoles by an organocatalytic (3+2) reaction has been established. The reaction makes use of simple indole derivatives as substrates and azoalkenes as 1,3‐diople reaction partners. A wide range of pyrroloindolines containing an all‐carbon quaternary stereogenic center were readily prepared in high yields and with excellent enantioselectivities. Abstract The enantioselective dearomatization of indoles by an organocatalytic (3+2) reaction has...
Thu Oct 24, 2019 14:20
Sb is the new B: A new family of Lewis acidic and hydridic diaminostibines were prepared and used in the catalyst‐ and initiator‐free hydrostibination of robust multiple bonds. The results further the concept of a diagonal relationship between boron and the heaviest Group 15 elements. Abstract A rigid naphthalenediamine framework has been used to prepare antimony hydrides that feature LUMO shapes and energies similar to those found in secondary boranes. By exploiting this feature, we introduce...
Thu Oct 24, 2019 14:18
Homogenization of Li nucleation from the nucleation stage and normalization of Li growth can be achieved on PNIPAM polymer brushes with lithiophilic functional groups modified Cu substrates. The obtained planar columnar Li anode exhibits excellent cycle stability at an ultra‐high current density of 20 mA cm−2. Abstract Inducing uniform deposition of lithium from the stage of metal crystallization nucleation is of vital importance to achieve dendrite‐free lithium anodes. Herein, using experiments...
Thu Oct 24, 2019 14:18
Amino‐functionalized aluminum reagents enable effective coordinative chain transfer polymerization of butadiene with selective chain initiation by the aminoalkyl substituent. This is illustrated visually by the fluorescence of carbazole end groups. Abstract Functionalized aluminum alkyls enable effective coordinative chain transfer polymerization with selective chain initiation by the functionalized alkyl. (ω‐Aminoalkyl)diisobutylaluminum reagents (12 examples studied) obtained by hydroalumination...
Thu Oct 24, 2019 14:16
In a fix: Graphene was introduced into Li‐N2 batteries to investigate the stability of the reaction cycle. The instability and hygroscopicity of the discharge product Li3N leads to the low efficiency and irreversibility of Li‐N2 batteries. Moreover, modification by in situ generated Li3N and LiOH reduces the loss and volume change of Li anodes during stripping and plating, thereby promoting the rechargeability of Li‐N2 batteries. Abstract Tremendous energy consumption is required for traditional...
Thu Oct 24, 2019 14:15
Unlocked: Dearomatization of indoles and their derivatives provides efficient synthetic routes for substituted indolines. For this asymmetric dearomatization reaction the indoles function as electrophiles. The combined utilization of a photocatalyst and chiral phosphoric acid (CPA) open to air unlocks the umpolung reactivity of indoles, enabling enantioselective dearomatization of indoles with N‐hydroxycarbamates as nucleophiles. Abstract Dearomatization of indoles provides efficient synthetic...
Thu Oct 24, 2019 14:15
“My favorite saying is ‘everybody is made of molecules’. My favorite molecule is water …” Find out more about Bing Xu in his Author Profile.
Thu Oct 24, 2019 14:15
The degradation mechanisms occurring during high‐voltage hold of supercapacitors are revealed through a self‐consistent approach combining operando analyses of evolving gases by electrochemical mass spectrometry (EMS) and post‐mortem analyses of electrodes by temperature programmed desorption–TPD. Abstract Enhancing the operating voltage of supercapacitors (SCs), hence their specific energy, is important. However, long‐term hold at high voltage entails loss of capacitance, increase of resistance...
Thu Oct 24, 2019 14:14
Within the framework: By controlling of the reductants and reaction conditions, reduction of 2,4,6‐tri(4‐pyridyl)‐1,3,5‐triazine (TPT) resulted in four radical anion salts and a diradical dianion salt. One of the radical anion salts forms one‐dimensional (1D) magnetic chain of TPT.−, and two of the others form radical metal‐organic frameworks (RMOFs). TPT..2− in the diradical dianion salt features an open‐shell singlet ground state. Abstract The reduction of 2,4,6‐tri(4‐pyridyl)‐1,3,5‐triazine...
Thu Oct 24, 2019 14:13
The effective manipulation of interfacial properties has broad implications for the development of high‐performance coatings. Metal–phenolic networks (MPNs) are an emerging class of responsive, universally adherent materials. Herein, we integrate host–guest chemistry with MPNs to modulate their surface chemistry and interfacial properties. Macrocyclic cyclodextrins (host) are conjugated to catechol or galloyl groups and subsequently used as components for the assembly of functional MPNs. The assembled...
Thu Oct 24, 2019 13:03
Metal on metal: Rhodium complexes with an indium metalloligand were successfully synthesized by utilizing a pyridine‐tethered cyclopentadienyl ligand as a support for an In−Rh bond. The indium metalloligand dramatically changes the electronic and redox properties of the rhodium metal, thereby conferring catalytic activity for sp2C−H bond activation. Abstract Rhodium complexes with an indium metalloligand were successfully synthesized by utilizing a pyridine‐tethered cyclopentadienyl ligand...
Wed Oct 23, 2019 22:00
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