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Comprehensive Summary: Lewis base catalyzed and Brønsted acid controlled chemodivergent electrophilic selenofunctionalizations of alkynes were developed for the first time. Various selenium‐containing tetrasubstituted alkenes were readily obtained in moderate to excellent yields with complete E/Z selectivities. As the substrates were 1‐ethynyl naphthol derivatives, linear selenium‐containing tetrasubstituted alkenes were produced via intermolecular oxygen nucleophilic attack in the absence of acid additive; in contrast, cyclic selenium‐containing tetrasubstituted alkenes were generated through intramolecular carbon nucleophilic capture with the addition of Brønsted acid. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Lewis base catalyzed and Brønsted acid controlled chemodivergent electrophilic selenofunctionalizations of alkynes were developed for the first time. Various selenium‐containing tetrasubstituted alkenes were readily obtained in moderate to excellent yields with complete E/Z selectivities. As the substrates were 1‐ethynyl naphthol derivatives, linear selenium‐containing tetrasubstituted alkenes were produced via intermolecular oxygen nucleophilic attack in the absence of acid additive; in contrast, cyclic selenium‐containing tetrasubstituted alkenes were generated through intramolecular carbon nucleophilic capture with the addition of Brønsted acid. [ABSTRACT FROM AUTHOR]

An efficient catalytic asymmetric electrophilic sulfenylation reaction for the synthesis of planar‐chiral sulfur‐containing cyclophanes has been developed for the first time. This was achieved by using a new Lewis base catalyst and a new ortho‐trifluoromethyl‐substituted sulfenylating reagent. Using the substrates with low rotational energy barrier, the transformation proceeded through a dynamic kinetic resolution, and the high rotational energy barrier of the substrates allowed the reaction to undergo a kinetic resolution process. Meanwhile, this transformation was compatible with a desymmetrization process when the symmetric substrates were used. Various planar‐chiral sulfur‐containing cyclophanes were readily obtained in moderate to excellent yields with moderate to excellent enantioselectivities (up to 97 % yield and 95 % ee). This approach was used to synthesize pharmaceutically relevant planar‐chiral sulfur‐containing molecules. Density functional theory calculations showed that π‐π interactions between the sulfenyl group and the aromatic ring in the substrate play a crucial role in enantioinduction in this sulfenylation reaction. [ABSTRACT FROM AUTHOR]

Recently, aqueous zinc‐based batteries (AZBs) have become a promising candidate for energy storage devices due to the high safety of aqueous electrolytes and the appealing features of Zn anodes, for example, low cost and high theoretical capacity. However, the excessive growth of Zn electrodeposits as well as the uneven stacking of large hexagonal Zn crystal units always render loose and irregular electrodeposition or even dendritic growth, which seriously deteriorates the actual performance of AZBs. Herein, to refine the grain size of Zn electrodeposits, a trace of Pb2+ ions as a novel electrolyte additive is performed to inhibit the growth of Zn grain during the Zn electrodeposition. Owing to the higher adsorption energy of Pb2+ ions on Zn crystal when compared with Zn2+ ions, the strongly positively‐charged Pb2+ ions are tightly absorbed on the typical crystal planes of initially‐formed Zn nuclei, which block the way for the subsequent absorption and electroreduction of Zn2+ ions. As a result, the Pb2+ ions‐containing electrolyte refines the grain size of Zn electrodeposits from 7.43–7.87 μm to 0.88–2.26 μm, and affords a high reversibility of Zn plating/stripping behavior with a high Coulombic efficiency of 99.9 % over 1000 cycles. [ABSTRACT FROM AUTHOR]

Aqueous Zn-based batteries deliver thousands of cycles at high rates but poor recyclability at low rates. Herein, we reveal that this illogical phenomenon is attributed to the reconstructed electrode/electrolyte interface at high rates, wherein the condensed electrical double layer (EDL) and the tightly absorbed Zn2+ ions on the Zn electrode surface afford compact and corrosion-resistant Zn deposits. [ABSTRACT FROM AUTHOR]

Vicinal dihalides not only emerge as reactive intermediates in synthetic organic chemistry, but also are extensively existing in bioactive marine natural products. The dihalogenation of alkenes is the most direct and effective method for the synthesis of vicinal dihalides. Because there is always an exchange process between the chiral haloniums and the unreacted olefins to cause racemization, the development of catalytic enantioselective dihalogenation of alkenes is of great difficulty. Recently, great progress has been made in catalytic asymmetric manner. However, there is a lack of related review of discussions of the mechanisms and reaction systems. This review is aimed at summarizing enantioselective dihalogenation of alkenes, including 1,2-dichlorination, 1,2-dibromination, and 1,2-difluorination, which is expected to encourage more researchers to participate in this field. 1 Introduction 2 Enantioselective 1,2-Dichlorination and 1,2-Dibromination of Alkenes 2.1 Chiral-Boron-Complex-Promoted Enantioselective 1,2-Dichlorination 2.2 Organocatalytic Asymmetric 1,2-Dichlorination and 1,2-Dibromination 2.3 Chiral-Titanium-Complex-Catalyzed 1,2-Dihalogenation 3 Chiral-Iodide-Catalyzed Enantioselective Oxidative 1,2-Difluorination 4 Summary and Outlook [ABSTRACT FROM AUTHOR]

An enantioselective sulfenylation/semipinacol rearrangement of 1,1‐disubstituted and trisubstituted allylic alcohols was accomplished with a chiral Lewis base and a chiral Brønsted acid as cocatalysts, generating various β‐arylthio ketones bearing an all‐carbon quaternary center in moderate to excellent yields and excellent enantioselectivities. These chiral arylthio ketone products are common intermediates with many applications, for example, in the design of new chiral catalysts/ligands and the total synthesis of natural products. Computational studies (DFT calculations) were carried out to explain the enantioselectivity and the role of the chiral Brønsted acid. Additionally, the synthetic utility of this method was exemplified by an enantioselective total synthesis of (−)‐herbertene and a one‐pot synthesis of a chiral sulfoxide and sulfone. [ABSTRACT FROM AUTHOR]

An efficient catalytic asymmetric electrophilic sulfenylation reaction for the synthesis of planar-chiral sulfur-containing cyclophanes has been developed for the first time. This was achieved by using a new Lewis base catalyst and a new ortho-trifluoromethyl-substituted sulfenylating reagent. Using the substrates with low rotational energy barrier, the transformation proceeded through a dynamic kinetic resolution, and the high rotational energy barrier of the substrates allowed the reaction to undergo a kinetic resolution process. Meanwhile, this transformation was compatible with a desymmetrization process when the symmetric substrates were used. Various planar-chiral sulfur-containing cyclophanes were readily obtained in moderate to excellent yields with moderate to excellent enantioselectivities (up to 97 % yield and 95 % ee). This approach was used to synthesize pharmaceutically relevant planar-chiral sulfur-containing molecules. Density functional theory calculations showed that π-π interactions between the sulfenyl group and the aromatic ring in the substrate play a crucial role in enantioinduction in this sulfenylation reaction., (© 2024 Wiley-VCH GmbH.)

Alkaline Zn-MnO 2 batteries feature high security, low cost, and environmental friendliness while suffering from severe electrochemical irreversibility for both the Zn anode and MnO 2 cathode. Although neutral electrolytes are supposed to improve the reversibility of the Zn anode, the MnO 2 cathode indeed experiences a capacity degradation caused by the Jahn-Teller effect of the Mn 3+ ion, thus shortening the lifespan of the neutral Zn-MnO 2 batteries. Theoretically, the MnO 2 cathode undergoes a highly reversible two-electron redox reaction of the MnO 2 /Mn 2+ couple in strongly acidic electrolytes. However, acidic electrolytes would inevitably accelerate the corrosion of the Zn anode, making long-lived acidic Zn-MnO 2 batteries impossible. Herein, to overcome the challenges faced by Zn-MnO 2 batteries, we propose a hybrid Zn-MnO 2 battery (HZMB) by coupling the neutral Zn anode with the acidic MnO 2 cathode, wherein the neutral anode and acidic cathode are separated by a proton-shuttle-shielding and hydrophobic-ion-conducting membrane. Benefiting from the optimized reaction conditions for both the MnO 2 cathode and Zn anode as well as the well-designed membrane, the HZMB exhibits a high working voltage of 2.05 V and a long lifespan of 2275 h (2000 cycles), breaking through the limitations of Zn-MnO 2 batteries in terms of voltage and cycle life.

An enantioselective selenocyclization of 1,1-disubstituted alkenes was achieved for the first time, which is enabled by a novel combination of a chiral BINAM-derived sulfide and an achiral Lewis acid. Various selenium-containing 4 H -3,1-benzoxazines, which are widely present in a range of medicinally relevant molecules, were readily obtained in moderate to good yields and good to excellent enantioselectivities. A series of tetrasubstituted carbon stereocenters were facilely constructed.

Enantioselective synthesis of axially chiral sulfur-containing biaryl derivatives through the electrophilic sulfenylation of biaryl phenols has been achieved for the first time. This catalytic asymmetric system, which involves sequential desymmetrization and kinetic resolution, is enabled by a combination of a novel 3,3'-disubstituted BINOL-derived selenide catalyst and an achiral sulfonic acid. Control experiments and computational studies suggest that multiple noncovalent interactions between the cocatalysts and substrate, especially a network of hydrogen bond interactions, play a crucial role in determining the enantioselectivity and reactivity.

An enantioselective sulfenylation/semipinacol rearrangement of 1,1-disubstituted and trisubstituted allylic alcohols was accomplished with a chiral Lewis base and a chiral Brønsted acid as cocatalysts, generating various β-arylthio ketones bearing an all-carbon quaternary center in moderate to excellent yields and excellent enantioselectivities. These chiral arylthio ketone products are common intermediates with many applications, for example, in the design of new chiral catalysts/ligands and the total synthesis of natural products. Computational studies (DFT calculations) were carried out to explain the enantioselectivity and the role of the chiral Brønsted acid. Additionally, the synthetic utility of this method was exemplified by an enantioselective total synthesis of (-)-herbertene and a one-pot synthesis of a chiral sulfoxide and sulfone., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)