Latest Articles(S, S)-Me-BI-DIME/Pd(0)-catalyzed ennantioselective C–H functionalization of N-ferrocenyl o-bromo-benzanilides has been realized, affording isoquinolinone-fused ferrocenes with up to 97% ee. The products can be transformed into planar chiral ferrocenyl monophosphines, which demonstrate their preliminary application.
A simple method to synthesize luminescent λ5-phosphanaphthalenes and zwitterionic nido-carborane fused six-membered phosphacycles was developed from the reaction of ortho-phosphinobenzoalde-hydes or ortho-phosphinocarboranylaldehydes with an electron-deficient alkyne, respectively. Similar results were obtained with the imino analogues.
The necessity to explore high-efficiency and high-value utilization strategy for biomass-waste is desirable. Herein, the strategy for direct conversion biomass-waste (rice husks) to Si/C composite structure anode was built. The Si/C composite materials were successfully obtained via the typical thermal reduction with magnesium, and the Si nanoparticle was uniformly embedded in carbon frame, as revealed by Raman, X-ray diffraction (XRD) and transmission electron microscope (TEM) measurement. The carbon structure among rice husks was effectively used as a protective layer to accommodate the volume variation of Si anode during the repeated lithiation/delithiation process. Benefitting from the structure design, the batteries show a superior electrochemical stability with the capacity retention rate above 90% after 150 cycles at the charge/discharge rate of 0.5 C (1 C = 600 mAh/g), and hold a high charge capacity of 420.7 mAh/g at the rate of 3 C. Therefore, our finding not only provides a promising design strategy for directly conversion biomass-waste to electrochemical storage materials but broadens the high-efficiency utilization method for other biomass by-products.
Polymeric nanomedicine is a promising and rapidly evolving field. Among the different polymeric carriers, polymeric micelle (PM) with nanoscale size exhibit potent physical and biological advantages including excellent solubility and pharmacokinetics, enhanced efficacy and lower toxicity. PM has garnered increasing interest in research and in the clinic. This review will highlight the clinical outcomes of several PM-based formulations, and further summarized their preparation methods, strengths and challenges.
Colorimetric sensing strategies as a powerful point-of-care testing (POCT) tool have attracted significant interest in various chem/biosensing applications. Taking the excellent bare-eye-detectable signaling feature, nanozymes-based colorimetric sensors enable more potential applications and have been a new forefront in the colorimetric POCT analysis toward different target analytes. However, the low catalytic activity of nanozymes in most cases limits their practical application. Recent efforts demonstrate that the aggregation-induced nanozymes provide a general means to modulate nanozymes activity and enhance colorimetric sensing performances of some nanozymes-based colorimetric sensors. But there are few reports are explored to discuss and review such aggregation-induced nanozymes and their colorimetric sensing applications. To highlight the advances and progress in aggregation-induced nanozymes based colorimetric assays, we herein summary the fundamentals, classify and applications of this newly-developing field, focusing on the aggregation-induced activity enhancement of nanozymes (AIAE-nanozymes) with a significant "signal-on" feature and aggregation-induced activity inhibition of nanozymes (AIAI-nanozymes) with a dramatical "signal-off" characteristics. Finally, we also propose the current challenges and the future prospects on both AIAE-nanozymes and AIAI-nanozymes.
Density functional theory calculations have been performed to investigate the copper-catalyzed borocyanation of 1-aryl-1,3-butadienes. The computations show that the regio- and enantioselectivity is determined by the borocupration step. The π-electron withdrawing aryl group at the C1 atom makes the C4 atom more electrophilic than the other carbon atoms, which together with the steric repulsion around the forming C—B bond, results in the experimentally observed exclusive 4,3-regioselectivity. The origins of the enantioselectivity were attributed to the steric effect and π-π stacking interaction between the butadiene moiety and the ligand.
Sulfonium salts and sulfur ylides are important S(Ⅳ) motifs, and have displayed many unique reactivities to provide simple, effective, and often stereoselective synthesis toward sulfur containing compounds. Impressive developments have been witnessed within this field during the past several years. In light of the increasing demand of organosulfur compounds across the range of chemical sciences, our aim of this review is to provide a concise overview of recent advances of sulfonium salt and sulfur ylide chemistry. Selected examples are organized in three parts on the basis of their role in organic reactions (reactants, intermediates and catalysts).
Generation of multi-substituted pyrroles is accomplished through an unexpected iron(Ⅱ)-promoted reaction of N-arylprop-2-yn-1-imines with water. This transformation proceeds smoothly with excellent chemoselectivity and regioselectivity. A stoichiometric amount of Fe(OTf)2 is necessary for the successful conversion. A Lewis acid-promoted tandem reaction pathway is proposed.
Two sulfonated seco C20-diterpenoid alkaloids, aconapelsulfonines A (1) and B (2), were isolated from an aqueous extract of the raw material of "Fu Zi" (the Aconitum carmichaelii lateral roots), of which the structures were elucidated by various spectroscopic data, combined with X-ray crystallographic analysis. The unprecedented skeletons are biogenetically proposed to be derived via Criegee rearrangements of the napelline-type architecture. The two compounds exhibited dose-depended analgesic activities on an acetic acid-induced mice writhing test.
A hierarchically structured MnOx-NiCo2O4 monolithic catalyst with rich phase interfaces was designed by a simple, eco-friendly and time-saving in-situ electro-deposition method. The abundance of active oxygen species due to this rich phase interfaces contributed to the excellent benzene combustion performance of MnOx-NiCo2O4-2:2 sample, oxidizing about 90% of benzene (T90) at 198 ℃ under 12000 h-1 gaseous hourly space velocity. This work shed new light on the design of excellent monolithic catalysts, which might pave the way for the industrialization of benzene combustion.