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Few‐layered MoSe2 nanosheets have great promise as a low‐cost alternative to noble Pt‐based electrocatalysts for electrochemical hydrogen evolution reaction (HER). In this work, arrays of ZnSe/MoSe2 nanotubes on fluorine‐doped tin oxide (FTO) glass substrates are synthesized and employed as an efficient binder‐free HER electrocatalyst for the first time. The hybrid ZnSe/MoSe2 nanotubes have thicknesses of 3–20 nm. The growth of ZnSe layer is attributed to ion exchange with ZnO nanorods while the formation of MoSe2 layer is resulted from chemical bath deposition. Compared with the bare MoSe2 electrocatalyst, the hybrid ZnSe/MoSe2 nanotube electrocatalyst exhibits striking kinetic metrics with a small Tafel slope (73 mV per decade) and a low onset potential (68 mV). Beside benefits from the nanoarray structure as binder‐free electrode as well as interlayer expansion of layered MoSe2, electron transfer from n‐type ZnSe to MoSe2 induced by alignment of energy levels at heterointerface contributes to fast electron transport and active electrocatalytic behavior of MoSe2 at the electrocatalyst–electrolyte interface, which is responsible for the significant improvement in HER performance. This work opens up a new door for developing high‐performance HER electrocatalysts by designing semiconductor heterojunction.

The first enantioselective conjugate addition of silyl ketene imines to in situ generated indol-2-ones was performed in the presence of a chiral N,N'-dioxide/Ni catalyst. This method provides efficient access to chiral β-alkyl nitriles bearing congested vicinal all-carbon quaternary stereocenters in up to 90 % yield with 23:1 d.r. and 98 % ee. The products enable facile transformations to chiral pyrroloindoline frameworks and spirocyclohexane oxindole derivatives. A possible transition state was also proposed to explain the origin of the asymmetric induction.

Ah ighly enantioselective formal conjugate allyl addition of allylboronic acids to b,g-unsaturated a-ketoesters has been realized by employing ac hiral Ni II /N,N'-dioxide complex as the catalyst. This transformation proceeds by an allylboration/oxy-Cope rearrangement sequence,p roviding af acile and rapid route to g-allyl-a-ketoesters with moderate to good yields (65-92 %) and excellent ee values (90-99 %ee). The isolation of 1,2-allylboration products provided insight into the mechanism of the subsequent oxy-Cope rearrangement reaction:s ubstrate-induced chiral transfer and ac hiral Lewis acid accelerated process.Based on the experimental investigations and DFT calculations,arare boatlike transition-state model is proposed as the origin of high chirality transfer during the oxy-Cope rearrangement.

An ew catalytic asymmetric tandem a-alkenyl addition/proton shift reaction of silyl enol ethers with ketimines was serendipitously discovered in the presence of chiral N,N'dioxide/Zn II complexes.T he proton shift preferentially proceeded instead of as ilyl shift after a-alkenyl addition of silyl enol ether to the ketimine.Awide range of b-amino silyl enol ethers were synthesized in high yields with good to excellent ee values.C ontrol experiments suggest that the Mukaiyama-Mannich reaction and tandem a-alkenyl addition/proton shift reaction are competitive reactions in the current catalytic system. The obtained b-amino silyl enol ethers were easily transformed into b-fluoroamines containing two vicinal tetrasubstituted carbon centers.

The asymmetric synthesis of γ-alkenyl butenolides was accomplished by conjugated addition of butenolides to alkynones. Both terminal alkynones and nonterminal alkynones were applicable to the N,N′-dioxide−scandium(III) catalytic system. The corresponding products were obtained in good to excellent yields (up to 99%) with high E/Z ratios and high enantioselectivities (up to 98% ee). The novel methods of building both γ-alkenyl butenolides and continuing epoxidation products facilitated constructing core structure of biologically active natural products and synthetic intermediates. Additionally, one-pot Michael addition/epoxidation performed well with our catalytic system.

A carbon film was prepared by filter paper and modified by radio-frequency magnetron sputtering as a conductive interlayer for lithium–sulfur batteries.

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