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Catalytic enantioselective preparation of alkene atropisomers with multiple stereogenic elements and discovery of their applications have become significant but challenging issues in the scientific community due to the unique structures of this class of atropisomers. We herein report the first catalytic atroposelective preparation of cyclopentenyl[b]indoles, a new kind of alkene atropisomers, with stereogenic point and axial chirality via an unusual rearrangement reaction of 3‐indolylmethanols under asymmetric organocatalysis. Notably, this novel type of alkene atropisomers have promising applications in developing chiral ligands or organocatalysts, discovering antitumor drug candidates and fluorescence imaging materials. Moreover, the theoretical calculations have elucidated the possible reaction mechanism and the non‐covalent interactions to control the enantioselectivity. This approach offers a new synthetic strategy for alkene atropisomers with multiple stereogenic elements, and represents the first catalytic enantioselective rearrangement reaction of 3‐indolylmethanols, which will advance the chemistry of atropisomers and chiral indole chemistry. [ABSTRACT FROM AUTHOR]

In the chemistry community, catalytic asymmetric synthesis of furan‐based compounds bearing both axial and central chirality has proven to be a significant but challenging issue owing to the importance and difficulty in constructing such frameworks. In this work, we have realized the first catalytic asymmetric synthesis of five‐five‐membered furan‐based compounds bearing both axial and central chirality via organocatalytic asymmetric (2+4) annulation of achiral furan‐indoles with 2,3‐indolyldimethanols with uncommon regioselectivity. By this strategy, furan‐indole compounds bearing both axial and central chirality were synthesized in high yields with excellent regio‐, diastereo‐, and enantioselectivities. Moreover, theoretical calculations were conducted to provide an in‐depth understanding of the reaction pathway, activation mode, and the origin of the selectivity. [ABSTRACT FROM AUTHOR]

With the rapid development of asymmetric catalysis, the demand for the enantioselective synthesis of complex and diverse molecules with different chiral elements is increasing. Owing to the unique features of atropisomerism, the catalytic asymmetric synthesis of atropisomers has attracted a considerable interest from the chemical science community. In particular, introducing additional chiral elements, such as carbon centered chirality, heteroatomic chirality, planar chirality, and helical chirality, into atropisomers provides an opportunity to incorporate new properties into axially chiral compounds, thus expanding the potential applications of atropisomers. Thus, it is important to perform catalytic asymmetric transformations to synthesize atropisomers bearing multiple chiral elements. In spite of challenges in such transformations, in recent years, chemists have devised powerful strategies under asymmetric organocatalysis or metal catalysis, synthesizing a wide range of enantioenriched atropisomers bearing multiple chiral elements. Therefore, the catalytic asymmetric synthesis of atropisomers bearing multiple chiral elements has become an emerging field. This review summarizes the rapid progress in this field and indicates challenges, thereby promoting this field to a new horizon. [ABSTRACT FROM AUTHOR]

Heterogeneously catalyzed N‐formylation of amines to formamide with CO2/H2 is highly attractive for the valorization of CO2. However, the relationship of the catalytic performance with the catalyst structure is still elusive. Herein, mixed valence catalysts containing Cu2O/Cu interface sites were constructed for this transformation. Both aliphatic primary and secondary amines with diverse structures were efficiently converted into the desired formamides with good to excellent yields. Combined ex and in situ catalyst characterization revealed that the presence of Cu2O/Cu interface sites was vital for the excellent catalytic activity. Density functional theory (DFT) calculations demonstrated that better catalytic activity of Cu2O/Cu(111) than Cu(111) is attributed to the assistance of oxygen at the Cu2O/Cu interface (Ointer) in formation of Ointer‐H moieties, which not only reduce the apparent barrier of HCOOH formation but also benefit the desorption of the desired N‐formylated amine, leading to high activity and selectivity. [ABSTRACT FROM AUTHOR]

This study establishes the first organocatalytic enantioselective synthesis of axially chiral N,N′‐bisindoles via chiral phosphoric acid‐catalyzed formal (3+2) cycloadditions of indole‐based enaminones as novel platform molecules with 2,3‐diketoesters, where de novo indole‐ring formation is involved. Using this new strategy, various axially chiral N,N′‐bisindoles were synthesized in good yields and with excellent enantioselectivities (up to 87 % yield and 96 % ee). More importantly, this class of axially chiral N,N′‐bisindoles exhibited some degree of cytotoxicity toward cancer cells and was derived into axially chiral phosphine ligands with high catalytic activity. This study provides a new strategy for enantioselective synthesis of axially chiral N,N′‐bisindoles using asymmetric organocatalysis and is the first to realize the applications of such scaffolds in medicinal chemistry and asymmetric catalysis. [ABSTRACT FROM AUTHOR]

Valuable formamides were "pulled out of the hat" upon reaction of amines with biomass‐based starting materials such as 1,3‐dihydroxyacetone, glycolaldehyde and glycerolaldehyde by avoiding any waste products using environmentally benign oxygen as oxidant, as reported by Haijun Jiao, Feng Shi, Jabor Rabeah, Angelika Brückner et al. in their Research Article (e202402241). This reaction may be regarded as "green" and somehow "magic"...By Xingchao Dai; Yunyan Han; Haijun Jiao; Feng Shi; Jabor Rabeah and Angelika BrücknerReported by Author; Author; Author; Author; Author; Author [Extracted from the article]

A new class of axially chiral styrene‐based thiourea tertiary amine catalysts, which have unique characteristics such as an efficient synthetic route, multiple chiral elements, and multiple activating groups, has been rationally designed. These new chiral catalysts have proven to be efficient organocatalysts, enabling the chemo‐, diastereo‐, and enantioselective (2+4) cyclization of 2‐benzothiazolimines with homophthalic anhydrides in good yields (up to 96 %) with excellent stereoselectivities (all >95:5 dr, up to 98 % ee). More importantly, theoretical calculations elucidated the important role of an axially chiral styrene moiety in controlling both the reactivity and enantioselectivity. This work not only represents the first design of styrene‐based chiral thiourea tertiary amine catalysts and the first catalytic asymmetric (2+4) cyclization of 2‐benzothiazolimines, but also gives an in‐depth understanding of axially chiral styrene‐based organocatalysts. [ABSTRACT FROM AUTHOR]

The regio‐ and enantioselective (3+3) cycloaddition of nitrones with 2‐indolylmethanols was accomplished by the cooperative catalysis of hexafluoroisopropanol (HFIP) and chiral phosphoric acid (CPA). Using this approach, a series of indole‐fused six‐membered heterocycles were synthesized in high yields (up to 98 %), with excellent enantioselectivities (up to 96 % ee) and exclusive regiospecificity. This approach enabled not only the first organocatalytic asymmetric (3+3) cycloaddition of nitrones but also the first C3‐nucleophilic asymmetric (3+3) cycloaddition of 2‐indolylmethanols. More importantly, theoretical calculations elucidated the role of the cocatalyst HFIP in helping CPA control the reactivity and enantioselectivity of the reaction, demonstrating a new mode of cooperative catalysis. [ABSTRACT FROM AUTHOR]

Light‐driven micropumps, which are based on electro‐osmosis with the electric field generated by photocatalytic reactions, are among most attractive research topics in chemical micromotors. Until now, research in this field has mainly been focused on the directional motion or collective behavior of microparticles, which lack practical applications. In this study, we have developed a photowelding strategy for repeated photoinduced conductivity recovery of cracked flexible circuits. We immersed the circuit in a suspension of conductive healing particles and applied photoillumination to the crack; photocatalysis of a predeposited pentacene (PEN) layer triggered electro‐osmotic effects to gather conductive particles at the crack, thus leading to conductivity recovery of the circuit. This photowelding strategy is a novel application of light‐driven micropumps and photocatalysis for conductivity restoration. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The first enantioselective construction of a new class of axially chiral naphthyl-indole skeletons has been established by organocatalytic asymmetric coupling reactions of 2-naphthols with 2-indolylmethanols (up to 99 % yield, 97:3 e.r.). This approach not only affords a new type of axially chiral heterobiaryl backbone, but also provides a new catalytic enantioselective strategy for constructing axially chiral biaryl scaffolds by making use of the C3-electrophilicity of 2-indolylmethanols. [ABSTRACT FROM AUTHOR]

The first catalytic asymmetric inverse-electron-demand (IED) oxa-Diels-Alder reaction of ortho-quinone methides, generated in situ from ortho-hydroxybenzyl alcohols, has been established. By selecting 3-methyl-2-vinylindoles as a class of competent dienophiles, this approach provides an efficient strategy to construct an enantioenriched chroman framework with three adjacent stereogenic centers in high yields and excellent stereoselectivities (up to 99 % yield, >95:5 d.r., 99.5:0.5 e.r.). The utilization of ortho-hydroxybenzyl alcohols as precursors of dienes and 3-methyl-2-vinylindoles as dienophiles, as well as the hydrogen-bonding activation mode of the substrates met the challenges of a catalytic asymmetric IED oxa-Diels-Alder reaction. [ABSTRACT FROM AUTHOR]

The cover page of the journal "Angewand Chemie" is presented.

Heterogeneously catalyzed N‐formylation of amines to formamide with CO2/H2 is highly attractive for the valorization of CO2. However, the relationship of the catalytic performance with the catalyst structure is still elusive. Herein, mixed valence catalysts containing Cu2O/Cu interface sites were constructed for this transformation. Both aliphatic primary and secondary amines with diverse structures were efficiently converted into the desired formamides with good to excellent yields. Combined ex and in situ catalyst characterization revealed that the presence of Cu2O/Cu interface sites was vital for the excellent catalytic activity. Density functional theory (DFT) calculations demonstrated that better catalytic activity of Cu2O/Cu(111) than Cu(111) is attributed to the assistance of oxygen at the Cu2O/Cu interface (Ointer) in formation of Ointer‐H moieties, which not only reduce the apparent barrier of HCOOH formation but also benefit the desorption of the desired N‐formylated amine, leading to high activity and selectivity. [ABSTRACT FROM AUTHOR]