Herein, we disclose the first manganese-catalyzed hydrosilylation of alkynes featuring diverse selectivities. The highly selective formation E-products was achieved by using mononuclear MnBr(CO)5 with arsenic ligand, AsPh3 . Whereas dinuclear catalyst Mn2 (CO)10 and LPO (dilauroyl peroxide) enabled reversed generation Z-products in good to excellent stereo- regioselectivity. Such a way controlling reaction stereoselectivity is unprecedented. Mechanistic experiments revealed dichotomy...

Abstract So far, the direct C−H alkenylation of aromatic nitriles with alkynes has not been achieved. Herein, we discribe first manganese‐catalyzed N−H imidates to access mono ‐alkenylated nitriles. The reaction is accelerated by presence a catalytic amount sodium pivalate. This protocol also highlighted simple system, good compatibility functional groups, and excellent mono‐/dialkenylation selectivity as well E / Z stereoselectivity. magnified image

Abstract Manganese‐catalyzed hydrosilylation of alkenes has been underdeveloped for a long time. Herein, we describe general, chemo‐ and regio‐ selective by using the Mn(CO) 5 Br catalyst with ample substrate scopes. Meanwhile, dehydrogenative silylation aryl olefins can be selectively achieved upon catalysis dinuclear Mn 2 (CO) 10 . Mechanistic experiments revealed diverse fates common intermediate β‐silyl radical, namely, hydrogen atom transfer (HAT) organometallic β‐H elimination olefins.

Hemostatic materials have played a significant role in mitigating traumatic injury by controlling bleeding, however, the fabrication of desirable material's structure to enhance accumulation blood cells and platelets for highly efficient hemostasis is still great challenge. In this work, directed assembly poly(vinyl alcohol) (PVA) macromolecules covering rigid Kevlar nanofiber (KNF) network during 3D printing process utilized fabricate hydrophilic, biocompatible, mechanically stable KNF-PVA...

Abstract Polyurethane foams were prepared from the liquefied cornstalk polyol, which was obtained by liquefaction of in presence polyhydric alcohols using sulfuric acid as catalyst. The advisable reaction conditions selected investigating their influences on properties taking account requirement for preparation appropriate polyurethane foams. contents catalysts, water, surfactant, and isocyanate also discussed, feasible formulations preparing cornstalk‐based proposed. results indicated that...

This paper presents a phase retrieval algorithm that incorporates sparsity priors into total variation and framelet regularization. The proposed exploits the in both gradient domain spatial distribution to impose desirable characteristics on reconstructed image. We utilize structured illuminated patterns holography, consisting of three light fields. theoretical numerical analyses demonstrate when illumination pattern parameters are non-integers, diffracted data sets sufficient for image...

Cobalt-free manganese-rich layered oxide is considered one of the most promising cathode materials for next-generation lithium-ion batteries due to its high capacity and low cost. However, irreversible anionic redox (OAR) leads serious failure problems hinders wide application. To solve above problems, entropy design strategy sites proposed, which more direct relevant regulation OAR process compared traditional TM sites. The entropic improves structural diversity long-range disorder...

Abstract Polyborylated organic compounds have been emerging as versatile building blocks in chemical synthesis. Here we report a selective cobalt-catalyzed deoxygenative 1,1,3-triborylation reaction of allylic ethers with pinacolborane to prepare 1,1,3-triborylalkane compounds. With naturally abundant and/or synthetic cinnamic methyl starting materials, achieved the synthesis variety 1,1,3-triborylalkanes (25 examples). The utility these is demonstrated through site-selective allylation,...

A rhenium and base co-catalyzed [3 + 2] carbocyclization of N–H ketimines alkynes through C–H bond activation is developed.

Abstract Herein, we disclose the first manganese‐catalyzed hydrosilylation of alkynes featuring diverse selectivities. The highly selective formation E ‐products was achieved by using mononuclear MnBr(CO) 5 with arsenic ligand, AsPh 3 . Whereas dinuclear catalyst Mn 2 (CO) 10 and LPO (dilauroyl peroxide) enabled reversed generation Z in good to excellent stereo‐ regioselectivity. Such a way controlling reaction stereoselectivity is unprecedented. Mechanistic experiments revealed dichotomy...

We have developed a cobalt-catalyzed regioselective 1,1,3-triborylation reaction of terminal alkynes with pinacolborane (HBpin) catalyst generated in situ from readily available and bench-stable Co(acac)2 xantphos. A variety undergo this triborylation reaction, affording the corresponding 1,1,3-triborylalkanes good yields high selectivity. The synthetic utility catalytic protocol has been demonstrated by developing selective stepwise functionalization 1,1,3-triborylalkane products. results...

The purpose of this study was to prepare the oleanolic acid–phospholipid complex (OA-PC) and then solidify it employing fumed silica by simple solvent evaporation technique improve dissolution rate acid complex. process OA-PC optimized type proportion were studied text. structures phospholipid solidified powder also characterized differential scanning calorimetry, X-ray diffraction, electron microscope. In tests, OA from further released compared with that pure in different kinds media....

Celestial navigation subsystem of airborne celestial/inertial integrated system periodically correct the positioning error and heading drift inertial system, by which can greatly improve accuracy long-endurance navigation. Thus celestial directly decides if it works for long time. By building mathematical model based on using method linear coordinate transformation, we establish transfer equation algorithm system. Based these built And then, analyze simulate are caused star tracking platform...

It is possible to enhance energy density in sodium-ion batteries by increasing the cutoff voltage, however, high voltage operation brings challenges performance of cathode materials. The integration honeycomb-like superlattice structures into materials has potential high-voltage performance; yet, risk irreparable structural damage occurring under extreme conditions cannot be ignored. This study introduces a valence element, Nb, an innovative manner, using its induced elemental segregation...

To overcome the disadvantage of current measurement methods using theodolites in an environment with shock and long working hours so on, this paper proposes a new method for 3D coordinate that is based on immovable measuring system. According to principle, mathematics model established uncertainty analysed. The function theodolite observation angles their uncertainty, can be reduced by optimizing theodolites' placement. Compared other methods, allows positions changed process, mutual...

The star sensor is a high-precision attitude sensitive measuring instruments, which determine spacecraft by detecting different positions on the celestial sphere. Imaging camera an important portion of sensor. purpose this study to design driving circuit based Kodak CCD KAI-04022 discussed, and timing analyzed. By testing laboratory imaging experiments, it found that circuits can meet requirements