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Comprehensive Summary: We report a palladium‐catalyzed asymmetric [4+4] cycloaddition reaction between 2‐alkylidenetrimethylene carbonate and electron‐deficient indole‐2,3‐quinodimethanes (IQDMs). This reaction features exclusive regioselectivity, high yield (up to 98%), excellent enantioselectivity (up to 95% ee), and easy scale‐up without any loss of efficiency, making it valuable for the synthesis of indole‐fused eight‐membered oxa‐rings. [ABSTRACT FROM AUTHOR]

Despite the considerable potential applications for helically chiral molecules across various sectors, their catalytic asymmetric synthesis remains nascent and has seen very limited advancement compared to that of central and axial chiral compounds, primarily owing to the scarcity of available starting materials and the immense challenges associated with achieving stereochemical control. Herein, we report an innovative approach to the facile synthesis and catalytic kinetic resolution of uniquely structured and stereochemically complex helical polycyclic phenols by using a steric hindrance-regulated enantioselective dearomative amination reaction. The distinguished aspects of this method include the exceptional stability of the dearomatized products and impressive versatility of the recovered substrates in the construction of enantioenriched helical frameworks. This work showcases that the strategic incorporation of appropriate steric groups near the reaction site of an electron-rich aromatic compound can indeed enable an interrupted Friedel-Crafts reaction, thus opening an alternate avenue for the study of dearomatization in nonfunctionalized arenes. [ABSTRACT FROM AUTHOR]

The first enantioselective Friedel‐Crafts (FC) allenylation reaction for the creation of central chirality is developed under cooperative Ir(I)/(phosphoramidite,olefin) and Lewis acid catalysis. This enantioconvergent reaction utilizes racemic allenylic alcohol as the electrophile and shows compatibility with a variety of electron‐rich arenes and heteroarenes. The resulting highly enantioenriched (up to >99.5 : 0.5 e.r.) 1,1‐disubstituted allenylic methanes, bearing a benzylic carbon stereocenter, are obtained with complete regiocontrol – both on (hetero)arenes as well as on the allenylic fragment. This protocol allows for the enantioselective formal introduction of a 4‐carbon alkyl chain into (hetero)arenes, along with the creation of a benzylic stereocenter. Judicious synthetic elaborations not only lead to formal enantioselective FC alkylation products of less electron‐rich arenes but also of substituted arenes in ortho‐ and even meta‐selective fashion. An intramolecular version of this FC allenylation is shown to proceed with promising enantioselectivity under the same catalytic conditions. Mechanistic studies revealed the involvement of dynamic kinetic asymmetric transformation (DyKAT) of racemic allenylic alcohols in this reaction. [ABSTRACT FROM AUTHOR]

A relay catalytic system is developed for the asymmetric hydrogenative coupling of indoles with α,β-unsaturated ketones, affording enantioenriched chiral γ-indole alcohols with broad substrate scope and excellent enantioselectivities (32 examples, up to >99% ee). Mechanistic studies suggest that the relay catalytic system consists of copper-catalyzed alkylation and ruthenium-catalyzed asymmetric hydrogenation. [ABSTRACT FROM AUTHOR]

A strategy driven and induced by cation-π interaction was employed to obtain a magnetic porous composite material (Fe3O4/PIN) with a uniform dispersion of ferroferric oxide (Fe3O4). Utilizing ferric chloride as the catalyst, indole-based porous polymer (PIN) was successfully synthesized through the Friedel-Crafts alkylation reaction. Concurrently with the preparation of the PIN, the cation-π interaction played a pivotal role, not only driving but also inducing the effective dispersion of iron ions from the catalyst around the indole groups. Subsequently, the introduction of ferrous sulfate into the reaction mixture triggered an in-situ reaction, resulting in the uniform distribution of Fe3O4 around the indole groups within the PIN. At a temperature of 298 K, Fe3O4/PIN demonstrated remarkable adsorption efficiency for TNT, boasting a maximum adsorption capacity of 290.697 mg/g, with the ability to achieve 74% of this capacity within one hour. Moreover, Fe3O4/PIN also exhibited a commendable adsorption efficiency for TNT in real water samples. In addition, Fe3O4/PIN could be recovered rapidly due to its excellent magnetic properties. After five adsorption-desorption cycles, the adsorption capacity of Fe3O4/PIN for TNT remained at 90% of its maximum capacity. Hence, Fe3O4/PIN was anticipated to serve as an effective adsorbent for TNT. The uniform distribution of Fe3O4 in porous materials through the driving and inducing effects of cation-π is an unprecedented innovation, offering a new perspective and approach to the synthesis and utilization of similar composite materials. [ABSTRACT FROM AUTHOR]

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]

Using highly sulfonated poly(ether ether ketone) (SPEEK) as the base material, the structure and properties of poly(ether ether ketone) (PEEK) membranes are optimized by precisely controlling the doping of phosphotungstic acid (HPW), dopamine (DA), and various amounts of carbon nanomaterials. Compared with conventional PEEK membranes, this optimized membrane exhibits higher proton conductivity, lower water absorption swelling rate, and excellent thermal stability. Highly SPEEK is soluble in water, thus fails to be used in fuel cell applications. Herein, we conduct Friedel‐Crafts method to obtain cross‐linked highly sulfonated membrane with controlled water uptake and swelling while still maintaining high proton conductivity. The polymer is then doped with phosphotungstic acid (HPW) to acquire enhanced performance. To control HPW leakage, polydopamine (PDA) acting as double‐sided adhesive is incorporated within the membrane. By distributing 1 wt.% PDA, the HPW leakage is reduced almost three times. The composite C‐SPEEK/HPWx/PDAy membranes have exhibited excellent overall performance. Specifically, the best proton conductivity result of C‐SPEEK/HPW50 has reached 0.271 S/cm. Moreover, it has presented superb performance in H2/O2 single cell test recorded as power density of 886.13 mW/cm2 while current density is 1614.20 mA/cm2 at 60°C. [ABSTRACT FROM AUTHOR]

Sulfur functional groups are ubiquitous in molecules used in the pharmaceutical and agrochemical industries, and within these collections sulfones hold a prominent position. The double aza‐analogues of sulfones, sulfondiimines, offer significant potential in discovery chemistry but to date their applications have been limited by the lack of convenient synthetic routes. The existing methods mainly rely on imination of low‐valent‐sulfur intermediates, or the combination of pre‐formed organometallic reagents and electrophilic S(VI)‐functionalities. Herein, we describe a Friedel–Crafts‐type reaction of sulfondiimidoyl fluorides with (hetero)aryls. This new SuFEx reactivity benefits from broad functional group tolerance, mild reaction conditions, and does not require the use of pre‐formed organometallic reagents. The efficient use of unprotected indoles and pyrroles, as well as furan, thiophene and carbocyclic aromatics, further demonstrates the advantages of these reactions. We show that the reactivity of the sulfondiimidoyl fluorides can be tuned by switching the N‐substituents, allowing an expansion of the range of coupling partners. The utility of the transformation is exemplified by the synthesis of the sulfondiimine analogue of the HIV‐I reverse transcriptase‐inhibitor L‐737,126. [ABSTRACT FROM AUTHOR]

The document is the contents list for the journal "Chemical Communications" published on October 4, 2024. It includes various articles and communications on topics such as solar energy, catalysis, coordination chemistry, and organic synthesis. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document provides a comprehensive overview of the articles included in the issue, allowing library patrons to quickly identify relevant research topics. [Extracted from the article]

The Friedel-Crafts alkylation reaction represents a pivotal organic transformation for the formation of carbon-carbon bonds, holding extensive applications within the realms of both organic synthesis and pharmaceutical chemistry. This article presents a comprehensive review of the mechanism underlying the Friedel-Crafts alkylation reaction, alongside recent advancements in various catalytic approaches, such as metal catalysis, organocatalysis, visible light photocatalysis, enzymatic and electrochemical catalysis. By merging cutting-edge scientific developments with undergraduate teaching content, this review endeavors to inspire students' learning interests while fostering their capacity for innovative thinking. [ABSTRACT FROM AUTHOR]

Chiral pincer complexes, characterized by their rigid tridentate coordination framework, have emerged as powerful catalysts in asymmetric synthesis. This review provides a comprehensive overview of recent advancements in the development of chiral pincer-type ligands and their corresponding transition metal complexes. We highlight the latest progress in their application across a range of catalytic asymmetric reactions, including the (transfer) hydrogenation of polar and non-polar bonds, hydrophosphination, alkynylation, Friedel-Crafts reactions, enantioselective reductive cyclization of alkynyl-tethered cyclohexadienones, enantioselective hydrosilylation, as well as Aza–Morita–Baylis–Hillman reactions. The structural rigidity and tunability of chiral pincer complexes enable precise control over stereoselectivity, resulting in high enantioselectivity and efficiency in complex molecular transformations. As the field advances, innovations in ligand design and the exploration of new metal centers are expected to expand the scope and utility of these catalysts, bearing significant implications for the synthesis of enantioenriched compounds in pharmaceuticals, materials science, and beyond. [ABSTRACT FROM AUTHOR]

Photocatalysis holds a pivotal position in modern organic synthesis, capable of inducing novel reactivities under mild and environmentally friendly reaction conditions. However, the merger of photocatalysis and transition‐metal‐catalyzed asymmetric C−H activation as an efficient and sustainable method for the construction of chiral molecules remains elusive and challenging. Herein, we develop a cobalt‐catalyzed enantioselective C−H activation reaction enabled by visible‐light photoredox catalysis, providing a synergistic catalytic strategy for the asymmetric dearomatization of indoles with high levels of enantioselectivity (96 % to >99 % ee). Mechanistic studies indicate that the excited photocatalyst was quenched by divalent cobalt species in the presence of Salox ligand, leading to the formation of catalytically active chiral Co(III) complex. Moreover, stoichiometric reactions of cobaltacycle intermediate with indole suggest that the irradiation of visible light also play a critical role in the dearomatization step. [ABSTRACT FROM AUTHOR]

The article focuses on recent advancements in chemistry, highlighting the development of new materials and chemical processes. Topics include the synthesis of insensitive energetic materials with enhanced detonation performance, the use of vanadium(V) complexes for syndiospecific ring-opening metathesis polymerization (ROMP) of cyclic olefins, and the exploration of metal-support interactions to enhance catalytic activity for hydrogen production.

The present work involves an improved, pseudo-three-component synthetic approach for the synthesis of dimeric indoles using 4 mol% [BCMIM][Cl] ionic liquid via metal-free synthesis in aqueous ethanol under reflux conditions. A series of 35 derivatives were furnished in up to 95% yields in 0.5 h to 1.5 h. These derivatives were then analyzed using various spectroscopic techniques. The salient features of this methodology are mild reaction conditions, metal-free synthesis, simple work-up procedure, short reaction time, reusability for up to 4 cycles, good to excellent yields and low catalyst loading. The UV-visible and fluorescence spectroscopy techniques were used to investigate the photophysical characteristics of selected derivatives. The absorption and emission spectra reveal a peak wavelength (λmax) in the ranges of 216–228 nm (π–π*), 262–294 nm (n–π*), and 389–407 nm, respectively. A similar trend to the experimental data can be observed in density functional theory (DFT) calculations. The binding affinities of the synthesised derivatives with bovine serum albumin (BSA) and deoxyribonucleic acid (DNA) were computed using AutoDock Vina. Furthermore, 7af, 7ai, 7aj and 7gk were investigated for BSA and DNA binding studies. The ligands exhibited a binding strength of 105 and 103 M−1 with BSA and DNA, respectively. The ethidium bromide (EtBr) displacement assay discloses intercalation as the mode of binding with Ksv values in the order of 102–103 M−1. [ABSTRACT FROM AUTHOR]

A mechanism‐navigated enantioselective alkylation of an indole C2 C−H bond with an internal alkene was developed. Under the unconventional ligand‐to‐metal catalyst ratio, a moderate enantiomeric ratio (er), ranging from 70:30 to 88:12, was achieved with our original ligand. We propose that chain‐walking and bond formation are mechanistically independent and suggest that hydridoiridium generated from the C−H source does not play a role in the chain‐walking process. [ABSTRACT FROM AUTHOR]

A highly enantioselective Pd/Bim-catalyzed dearomative Michael reaction applying polycyclic tropones as non-benzenoid aromatic Michael acceptors and arylboronic acids as aryl pronucleophiles has been developed. The bridged biaryls bearing central and axial chirality, including pentacyclic cyclohepta[b]indoles and 6,7-dihydrodibenzo- [a,c][7]annulen-5-ones, are generally generated in good to high yields and excellent enantioselectivities and can be readily transformed into useful derivatives. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal Chemical Communications. It provides a list of articles and their authors that are featured in the journal's latest issue. The articles cover a range of topics in the field of chemistry, including electrocatalytic water-to-oxygen conversion, catalyst development for oxidative dehydrogenation, and photomechanical properties in metal-organic crystals. The journal aims to connect the global chemistry community and invest its profits back into the field. [Extracted from the article]

We synthesized a cyclic molecule from diarylalkynes and Meldrum's acid derivatives as the methylenation reagent via double Friedel–Crafts reaction. Single-crystal X-ray structure analysis confirmed the twisted structure of the molecule. We also investigated their physical properties and homoconjugation by UV-Vis, photoluminescence, DFT and TD-DFT calculations. [ABSTRACT FROM AUTHOR]

In 1,1,1,3,3,3‐hexafluoroisopropyl alcohol (HFIP), gem‐bis(triflyl)cyclobutenes, which can be prepared by the (2+2) cycloaddition reaction of Tf2C=CH2 with alkynes, underwent desulfination to generate the corresponding cyclobutenyl cation. This unique reactivity was successfully applied to the Friedel–Crafts type cyclobutenylation reaction of several (hetero)aromatic compounds. [ABSTRACT FROM AUTHOR]

A hitherto unknown class of C4‐symmetric Caryl−Cβ (C3, C8, C13, C18) axially chiral porphyrins has been synthesized and the application of their iridium (Ir) complexes in catalytic asymmetric C(sp3)−H functionalization is documented. Cyclotetramerization of enantioenriched axially chiral 2‐hydroxymethyl‐3‐naphthyl pyrroles under mild acidic conditions affords, after oxidation with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ), the C4‐symmetric α,α,α,α‐atropenantiomer as an only isolable diastereomer. Both regioisomeric Ir(Por*)(CO)(Cl) complexes catalyze the carbene C−H insertion reaction affording the same enantiomer, albeit with slight difference in enantioselectivity. With the optimum Ir‐complex 3 e, the 2‐substituted arylacetic acid derivatives were generated from diazo compounds and cyclohexadiene in excellent yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

The use of halogen bonding interactions as an alternative to acid and metal catalysts for substrate activation has gained popularity in recent years. In this work we demonstrate a halogen bond assisted activation of chalcones under visible light irradiation for the Friedel‐Crafts reaction with indole to yield β‐indolylketones. The simple and scalable protocol uses the readily available CBr4 as halogen bond catalyst. The targets are produced in 31–94% of yield with excellent functional group tolerance. The proposed mechanism of the reaction is supported by UV‐vis, fluorescence, and NMR spectroscopic studies. Further it is demonstrated that the β‐indolylketones can be oxidised to indole substituted α, β‐unsaturated ketones by DDQ or cyclized to thieno[2,3‐b]indoles in the presence of elemental sulfur and base. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The privileged C2‐symmetric rigid phenol‐type ligand is more attractive but challenging in asymmetric catalysis. Herein, we designed and synthesized a class of rigid‐featured chiral tridentate Phenol‐2NO ligands, that incorporate the advantages of both the phenol skeleton and pyrroloimidazolone‐based N‐oxide moiety, from readily available L‐prolinamides in operationally simple two steps and up to 44% overall yield. More importantly, using an achiral quinoline derivative as an additive, the newly developed Phenol‐2NO ligand could serve as the anioic ligand upon deprotonative activation to coordinate to Zn(II) to form a highly enantioselective catalyst for the asymmetric Michael‐type Friedel‐Crafts alkylation reaction of indoles with 2,3‐dioxopyrrolidines. Excellent yields (up to 90%) and high enantioselectivities (up to 99% ee) are obtained for a wide range of substrates under mild conditions. Experiments and DFT calculations revealed the reaction mechanism and the origins of the enantioselectivity. This also represented the first activation of phenol‐type ligand/metal complex by an achiral organic base as the additive in asymmetric catalysis. [ABSTRACT FROM AUTHOR]

We report the construction of C5‐indole unnatural amino acid derivatives via the diastereoselective Pd(II)‐catalyzed prochiral β‐C(sp3)‐H arylation of racemic (DL), and enantiopure L‐ and D‐carboxamides of amino acids with 5‐iodoindoles. Independently, indole‐based compounds and amino acid motifs are important small molecules in organic synthesis and drug discovery research. This report aimed to contribute to enriching the library of indole‐based unnatural amino acid derivatives. The synthesis of examples of C5‐indole motif‐installed amino acid derivatives comprising norvaline, phenylalanine, leucine, norleucine, 2‐aminooctanoic acid having anti‐stereochemistry was accomplished. The synthesis of the C5‐indole motif‐containing non‐α‐amino acid (aminoalkanoic acid) derivatives was also reported. The C−H arylation reactions of racemic and enantiopure carboxamides with 5‐iodoindoles afforded the corresponding indole unnatural amino acid derivatives with good diastereoselectivity (anti, dr>95 : 5 and enantiopurity (er up to 99 : 1). Removal of the directing group (8‐aminoquinoline), phthalimide group and preparation of indole amino acid esters and free amino group‐containing indole unnatural amino acid motifs were also shown. The utility of the methodology was shown by synthesizing indole motif‐containing pyrrolidone and peptide molecules. The stereochemistry of the major (anti) diastereomers was ascertained from the X‐ray structure of a representative compound. [ABSTRACT FROM AUTHOR]

In this study, triphenylaniline-based porous organic polymers (TPA-POPs) were successfully prepared by the Friedel–Crafts reaction and applied to adsorb malachite green (MG) dye from water. The TPA-POP was characterized using TEM, SEM, FTIR, 13C (CP/MAS) NMR, BET surface area, and XRD analysis. The results exhibited that the TPA-POP has a high surface area (1625.14 m2/g) with pore volume (0.353 cm3/g) and pore radius (1.57 nm) that reflect the high quantity of MG adsorbed on the TPA-POP. The polymer was evaluated as an excellent adsorbent for MG adsorption from water using the batch method. MG dye removal was optimized as 99.60% (at pH: 6.0, adsorbent dosage (m): 0.01 g, temperature (T): 45 °C, and contact time (t): 300 min). The kinetic data follow the Elovich model, while the isotherm data fit the Langmuir model well with uptake capacity (755.72 mg/g) at T: 45 °C. According to thermodynamic parameters, the adsorption process was endothermic and spontaneous. The adsorption of MG on the TPA-POP occurred via different mechanisms (π–π interaction, electrostatic attraction, and hydrogen bonding). Reusability experiments exhibited that the TPA-POP still maintained high removal efficiency (82.12%) after five cycles. In conclusion, the TPA-POP is a promising adsorbent owing to its cost-effectiveness, high adsorption capacity, high surface area, excellent reusability, and efficient MG removal from aqueous media. [ABSTRACT FROM AUTHOR]

Two metal‐ and acid‐free anthracene (AN) and anthraquinone (AQ)‐based photocatalysts (HCP‐AQ‐2Ph and HCP‐AN‐2Ph) are synthesized and used for the effective acetalization of glycerol to obtain selectively solketal, an added‐value compound with several industrial applications and high demand as an oxygenated additive of fuels. HCP‐AQ‐2Ph and HCP‐AN‐2Ph are prepared by a Friedel–Crafts coupling reaction between the AQ or AN and biphenyl (2Ph) as comonomer which leads to the formation of high thermally stable hyper‐crosslinked porous networks with specific surface areas of 295 and 596 m2 g−1, respectively. Initial tests suggest that HCP‐AN‐2Ph is a less efficient catalyst compared to HCP‐AQ‐2Ph. However, subsequent runs indicate that during the first trial, the AN units are oxidized, resulting in a catalyst (HCP‐AN(OX)‐2Ph) just as effective as the AQ‐based one. The quantitative and selective conversion of glycerol into solketal is achieved in just 3 h using a 4 wt% catalyst and maintaining this catalytic performance for at least 5 cycles. In addition, the process can be scaled allowing the obtaining of solketal with high purity on a gram scale. These results place these catalysts among the most effective for the selective production of solketal from glycerol compared to previously reported metal‐ or acid‐catalyzed reaction. [ABSTRACT FROM AUTHOR]

A ethylene - octene copolymer (OBC)/waste polystyrene (WPS) compatibilizing masterbatch was prepared through the Friedel-Crafts alkylation reaction. The effects of anhydrous; AlCl3 dossage on the grafting rate of WPS and the properties of the masterbatch and the effects of the masterbatch dosage on the comprehensive performance of ethylene -propylene-diene rubber (EPDM) were investigated. The results indicated that WPS could react with OBC to form an OBC-g-WPS graft copolymer. There was no gelation at an anhydrous AlCl3 dosage of 0. 4 and a WPS grafting rate of 25. 3 wt%, resulting in the best comprehensive properties of the masterbatch. When this compatibilizing masterbatch was used for EPDM, the resultant rubber exhibited higher tensile strength, higher tear strength, and better heat aging resistance than pure EPDM vulcanized rubber, and its performance was also better than that of the EPDM containing the same amount of an OBC/WPS physical blend. Scanning electron microscopy indicated that WPS was uniformly dispersed in the vulcanized EPDM rubber with the addition of the OBC/WPS compatibilizing masterbatch. [ABSTRACT FROM AUTHOR]

Herein, we report a chiral Brønsted acid‐catalyzed enantioselective Friedel‐Crafts reaction of ortho‐alkynylnaphthols with various naphthofurans, realizing the asymmetric synthesis of axially chiral styrenes with naphthofurans in 67 to 93% yield and with 34 to 96% ee. [ABSTRACT FROM AUTHOR]

Takemoto's catalysts were used to organocatalyze the enantioselective Friedel–Crafts reaction with different electron-rich phenols and substituted isatins. The resulting 3-aryl-3-hydroxyl-2-oxindoles were obtained in good yields (85–96%) with up to 99% ee. The substrate scope was broadened with this methodology compared to reported examples catalyzed by cinchonidine thiourea. [ABSTRACT FROM AUTHOR]

This article provides an overview of photoredox-catalyzed C(sp2)–H bond functionalization reactions, which use low-energy photons to enable reactions under mild conditions. It discusses the contributions of researchers in advancing the field and explores the potential of using organic photocatalysts. The article focuses on the author's group's work in utilizing these reactions for C–H bond functionalizations, specifically in the context of enamides. The researchers explored various reactions, including the functionalization of enamide β-C(sp2)-H bonds, phosphorylation of alkenyl C(sp2)-H bonds, and bromination and alkylation of (hetero)arene C(sp2)-H bonds. These reactions have applications in the synthesis of natural products and pharmaceuticals, and further research is needed to develop new transformations and expand their applications. [Extracted from the article]

Herein, we present an efficient and atom‐economic tandem hydroformylation organocatalyzed Friedel‐Crafts reaction sequence for the synthesis of diindolylmethanes. Classic syntheses have relied on (Lewis) acid activation of aldehydes, which are often not commercially available and rather sensitive in handling. In contrast, the combination of rhodium‐catalyzed hydroformylation and subsequent organocatalytic activation of the in‐situ formed aldehydes allows the use of readily available and stable alkenes with various functional groups while avoiding acidic conditions to expand the range of available diindolylmethanes. A broad scope of diindolylmethanes was prepared in yields up to 85 % demonstrates the utility of the presented method. [ABSTRACT FROM AUTHOR]

We report on the synthesis and characterization of a series of (mostly) air‐stable diorganyl bis(pyridylimino) isoindolide (BPI) aluminum complexes and their chemistry upon visible‐light excitation. The redox non‐innocent BPI pincer ligand allows for efficient charge transfer homolytic processes of the title compounds. This makes them a universal platform for the generation of carbon‐centered radicals. The photo‐induced homolytic cleavage of the Al−C bonds was investigated by means of stationary and transient UV/Vis spectroscopy, spin trapping experiments, as well as EPR and NMR spectroscopy. The experimental findings were supported by quantum chemical calculations. Reactivity studies enabled the utilization of the aluminum complexes as reactants in tin‐free Giese‐type reactions and carbonyl alkylations under ambient conditions, which both indicated radical‐polar crossover behavior. A deeper understanding of the physical fundamentals and photochemical process was provided, furnishing in turn a new strategy to control the reactivity of bench‐stable aluminum organometallics. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel synthesis method of HCPs with more mesoporous and hetero atoms, which is through the incorporation of functional macromolecules. • Tetraphenylporphyrin zinc (TPP-Zn) doped HCP-based hard carbon (CTHCP) with stable structure was prepared by Friedel-Crafts reaction. • Uncovered the design rules of HC anode materials suitable for Li+/Na+ batteries and provided a new idea for the preparation of high-performance HC anode materials. Hyper cross-linked polymers (HCPs), as a key precursor of hard carbon (HC) anode materials, stand out because of their capacity for molecular-scale structural design and comparatively straightforward preparation techniques, which are not seen in other porous materials synthesized procedure. A novel synthesis method of HCPs is developed in this paper, which is through the incorporation of functional macromolecules, the structural control and heteroatom doping of the product has been achieved, thus augmenting its electrochemical performance in batteries. In this work, carbonized tetraphenylporphyrin zinc (TPP-Zn) doped HCP-based hard carbon (CTHCP) with stable structure was prepared by Friedel-Crafts reaction and carbonization by using naphthalene and trace TPP-Zn as monomers, dimethoxybenzene (DMB) as crosslinking agent and FeCl 3 as catalyst. The introduction of TPP-Zn, a functional macromolecule with unique two-dimensional structure, realized the pore structure regulation and N doping of the raw carbonized HCP-based hard carbon (CHCP). The results showed that CTHCP had higher mesoporous volume, N content and wider layer spacing than CHCP. In addition, CTHCP anode exhibited excellent Li+/Na+ storage performance, initial reversible capacity, rate performance and long cycle life. More amount of N -containing (N-5) active sites and mesoporous content in CTHCP anode was the main reason for the improvement of Na+ storage effect. While the increased interlayer spacing had a greater effect on the lithium storage capacity. This study uncovered the design rules of HC anode materials suitable for Li+/Na+ batteries and provided a new idea for the preparation of high-performance HC anode materials. [ABSTRACT FROM AUTHOR]

High temperature proton exchange membrane (HT-PEM) is a core component for high temperature proton exchange membrane fuel cells (HT-PEMFCs). Although phosphoric acid (PA) doped polybenzimidazole (PBI) membranes are widely applied in HT-PEMFCs, the synthetic procedure is rather tough and the carcinogenic monomer should be used. Thus, it is of significance to obtain cheaper and easily prepared HT-PEMs with moderate physicochemical properties and good fuel cell performance. Herein, using a straightforward Friedel-Crafts reaction between 4-acetylpyridine, biphenyl and para -terphenyl, a series of poly(biphenyl- co -terphenyl pyridine) copolymers (Co- x %BP- y %TP) are developed. The obtained Co- x %BP- y %TP membranes exhibit excellent capability of absorbing PA owing to the existence of pyridine units in polymers, and meanwhile PA absorption capacity of membranes increase with the increased percentage of the biphenyl moiety in copolymers. Through immersing in 85 wt% PA at 100 °C, the Co–25%BP-75%TP membrane achieves a PA uptake of 274%, displays a moderate tensile strength of 4.7 MPa and possesses a high conductivity of 0.099 S cm−1 at 180 °C. Consequently, under 200 °C and no backpressure condition, the peak power density of the H 2 –O 2 cell equipped with Co–25%BP-75%TP/274%PA membrane reached a high value of 773 mW cm−2, demonstrating a big potential to be operated in HT-PEMFCs. • Series of poly(biphenyl- co -terphenyl pyridine) copolymers are synthesized through one-step polymerization. • Co–25%BP-75%TP/274%PA shows a high conductivity of 0.099 S cm−1 at 180 °C. • HT-PEMFCl with Co–25%BP-75%TP/274%PA exhibits a high peak power density of 773 mW cm−2 at 200 °C. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive review of the total synthesis of ferruginol, an aromatic abietane diterpenoid. Ferruginol is known for its unique structure and diverse range of bioactive natural products. The article explores the biological activity of ferruginol, including its antimicrobial, antioxidant, antitumor, and antimalarial properties. It also discusses various synthesis strategies used for ferruginol, such as the Bogert-Cook synthesis and Robinson annulation. The article emphasizes the achievements and methodologies used in the total synthesis of ferruginol, offering valuable insights for researchers in the field. [Extracted from the article]

The Friedel‐Crafts reaction stands as a powerful synthetic tool for C−H functionalization of aromatic feedstocks, which is conventionally realized through electrophilic alkylation and acylation. The burgeoning interests in axially chiral compounds across diverse fields have spurred extensive exploration of this classic transformation for catalytic atroposelective synthesis. Consequently, the past decade has witnessed the rapid expansion of various non‐canonical Friedel‐Crafts reactions, including electrophilic arylation, alkenylation, halogenation, sulfenylation, and amination of aryl C−H bonds, thereby delving into new chemical spaces. A range of catalytic atroposelective synthetic methods have been devised for these significant arene C−H functionalization. This review provides a comprehensive overview of the cutting‐edge catalytic synthesis of atropoisomers through non‐canonical Friedel‐Crafts reactions, categorized into three parts based on the type of bond formation on the aromatics: C(sp2)−C(sp3) bond formations, C(sp2)−C(sp2) bond formations and C(sp2)−heteroatom bond formations. The richness of electrophiles and the modulation of atroposelectivity by diverse chiral organocatalysts, particularly chiral Brønsted acids, are elucidated. We anticipate that the repertoire of asymmetric Friedel‐Crafts reaction will continue to flourish and to be demonstrated in not only scientific researches but also industrial organic synthesis. [ABSTRACT FROM AUTHOR]

Among inherently chiral selectors of axial stereogenicity, usually resulting in very good enantiodiscrimination performances, the biindole‐based family has the additional advantage of very easy functionalization of the two nitrogen atoms with a variety of substituents with desirable properties. Aiming to evaluate the possibility of exploiting such feature to enhance the enantiodiscrimination ability of the archetype structure, a series of three inherently chiral monomers were designed and synthesized, characterised by a 2,2'‐biindole atropisomeric core conjugated to bithiophene wings enabling fast and regular electrooligomerization, and functionalised at the nitrogen atoms with an ethyl, a methoxyethyl, or a hydroxyethyl substituent. Nitrogen alkylation was also exploited to obtain for the first time the chemical resolution of the biindole selectors without employing chiral HPLC. The enantiodiscrimination ability of the selector series was comparatively evaluated in proof‐of‐concept chiral voltammetry experiments with a "benchmark" chiral ferrocenyl probe as well as with chiral non‐steroidal anti‐inflammatory drugs naproxen and ketoprofen. The large enantiomer potential differences for all probes increased in the ethyl < methoxyethyl ≪ hydroxyethyl sequence of selector substituents, supporting our assumption on the beneficial role of an additional coordination element. The powerful hydroxyethyl selector was also applied to ketoprofen in a commercial drug matrix. [ABSTRACT FROM AUTHOR]

As phenanthroline (phen) possesses great coordination ability with various ions, the development of new chiral phen ligands is in great demand in asymmetric catalysis. Herein, we rationally designed and developed an entirely new class of C2-symmetric rigid-featured chiral phen ligands that provide the N,N,O,O-tetradentate coordination of the phen moiety and two additional N,N-dioxides. The chiral ligands, termed Phen-2NO ligands, incorporate the advantages of both the phen skeleton and the pyrroloimidazolone-based N-oxide moiety, and their electronic and steric properties can be readily tuned through the incorporation of substituents in the aromatic rings of the amide group. These ligands presented a superior performance in the Ni(II)-catalyzed asymmetric Michael-type Friedel–Crafts alkylation reaction of indoles with β,γ-unsaturated α-ketoesters. Excellent yields (up to 93%) and high enantioselectivities (up to 99% ee) are obtained for a wide range of substrates under mild conditions. These results demonstrated the promising potential of the Phen-2NO ligand as an efficient chiral phen ligand. [ABSTRACT FROM AUTHOR]

Long‐range conjugated structures are important for increasing the conductivity and broadening the application scope of hypercrosslinked polymers (HCPs). It is, however, difficult to fabricate long‐range conjugated structures using conventional HCP synthesis methods. Herein, we report a simple and efficient strategy for the synthesis of HCPs with extended π‐conjugated structures through Friedel–Crafts and intramolecular Scholl‐coupling reactions from readily available aromatic compounds under mild conditions. Two conjugated HCPs (C‐HCPs), namely, C‐HCP‐ATA and C‐HCP‐TPB, were prepared from anthracene (ATA) and triphenylbenzene (TPB), respectively, using this method. The proposed strategy not only ensures a high specific surface area of materials but also introduces a long‐range conjugated structure into HCPs. The lithium‐ion battery applications of the C‐HCPs were investigated. As anode materials, C‐HCP‐ATA and C‐HCP‐TPB displayed higher lithium storage capacities, better conductivity, and higher stability than their precursors, HCP‐ATA and HCP‐TPB, which were prepared using the conventional method. [ABSTRACT FROM AUTHOR]

Herein, two sulfhydryl‐functionalized polymers, namely, EDT‐HCPS and TMPMP‐HCPS, were synthesized according to the Friedel‐Craft s alkylation and nucleophilic substitution, and they were used to adsorb Pd2+ and Ag+ from aqueous solution. The Friedel‐Crafts alkylation offered the polymers with hyper‐cross‐linking frameworks composed of plentiful rigid methylene. The nucleophilic substitution brought abundant functional SH groups (the sulfur contents were 12.6 and 9.4 wt%, respectively) to the polymers. The adsorption results showed that the capacities of Pd2+ and Ag+ on EDT‐HCPS were larger than TMPMP‐HCPS, and the higher quantities of functional SH groups and the porosity played a beneficial role. The equilibrium data can be characterized by the Langmuir model, and the maximum capacities of Pd2+ and Ag+ on EDT‐HCPS at 308 K were predicted to be 383.92 and 212.93 mg g−1, respectively. The produced polymers represented superior adsorption selectivity, reproducibility, and reusability, demonstrating their excellent performance for the adsorption of Pd2+ and Ag+, and analysis of the adsorption mechanism demonstrated that the SH groups played a major role due to the strong chemical complexation of the functional SH with Pd2+/Ag+. [ABSTRACT FROM AUTHOR]

Different ratios of octavinylsilsesquioxane (OVS) reacted with phenyl‐substituted double‐decker silsesquioxane (Ph‐DDSQ) via the simple Friedel‐Crafts reaction provides several innovative silsesquioxane‐based porous polymers (PCS‐ODs). The hybrid polymers show adjustable porosity (specific surface areas of 1235 m2 g−1 and large pore volumes >1.07 cm3 g−1). FTIR, SEM, BET, TGA, solid‐state 13C and 29Si MAS NMR spectra were employed to fully characterize these hybrid materials. They display good adsorption capacities for neonicotinoid insecticides (imidacloprid [IMI], acetamidine [ACE] and thiamethoxam [THI]), with capacities up to 117 ± 2, 70 ± 1 and 61 ± 4 mg g−1, respectively. Dyes (Congo red [CR] and rhodamine B [RB]) can also be sufficiently removed, the adsorption capacities are 1822 ± 4 and 912 ± 3 mg g−1. In addition, PCS‐ODs can be cycled at least five times. [ABSTRACT FROM AUTHOR]

Human society faces significant environmental challenges due to the rapid production and consumption of fossil fuels. Therefore, developing effective and environmentally friendly methods of generating and storing energy is essential. Hypercrosslinked polymers (HPPs) have become increasingly popular due to their diverse preparation methods, simple functionalization, large specific surface area, low cost, mild reaction conditions, high chemical and thermal stability, and small size. We synthesized two hypercrosslinked porous organic polymers using Friedel‐Crafts reactions of 2,3,5,6‐tetraphenyl pyrazine (Pyra) with 4,4′‐bis(chloromethyl)biphenyl (BP), and dimethoxymethane (DDM), resulting in Pyra‐BP‐HPP and Pyra‐DDM‐HPP, respectively. The chemical structures and thermal stability of these polymers were confirmed through solid‐state 13C NMR, FTIR, and TGA. The surface area of Pyra‐BP‐HPP and Pyra‐DDM‐HPP was determined to be 984 and 435 m2 g−1, respectively, with micro and mesoporous structures present. Pyra‐BP‐HPP displayed a high specific capacitance of 94 F g−1 at 1 A g−1, with a capacity retention of 95% after 2000 cycles, which can be attributed to its larger surface area, microporosity, and abundance of electron‐rich phenyl rings when compared to Pyra‐DDM‐HPP. [ABSTRACT FROM AUTHOR]

Herein, we report the selective synthesis of 3‐hydroxy bisindoles via an engineered myoglobin‐catalyzed Friedel–Crafts reaction of isatin and indole. Initially, the reaction was carried out using wild‐type myoglobin as a catalyst, but the conversion was low. Therefore, a library of Mb‐variants was generated utilizing a site‐directed mutagenesis technique and obtained the double‐mutated Mb(H64V, V68A) variant as a highly reactive and selective biocatalyst for this transformation. Additionally, the robustness and generality of this protocol have been demonstrated by setting up scale‐up reactions of variously substituted isatins and indoles which produce the desired 3‐hydroxy bisindoles in 66–93 % isolated yield. Next, the enzymatic approach was combined with an carbocatalytic protocol by using graphene oxide as a catalyst to generate C‐3 sulfenylated bisindole derivatives in a one‐pot manner. [ABSTRACT FROM AUTHOR]

Objective: Design and synthesis of two chalcone derivatives, evaluation of their anticancer and antiinflamatory activities. Methods: The ring-closure through an intramolecular Friedel-Crafts reaction followed by an alkaline-catalyzed Claisen-Schmidt condensation. MTT assay was conducted in anticancer activity. The chalcone derivatives tested for anti-inflammatory immunomodulatory potential by measuring pro-inflammatory cytokines production levels. Results and Discussion: Both compounds displayed anti-inflammatory effects on activated mammalian cells without being cytotoxic. Their low toxicity resulted in high IC50 values in glioblastoma cells, indicating they are safe anti-inflammatory agents, yet lack anti-cancer properties. Conclusions: Synthesized and characterized two chalcone derivatives that displayed comparable anti-inflammatory effects, reducing TNF, IL6, GMCSF, and IL12p40 levels without harming macrophages. Their high IC50 values in glioblastoma cells suggest low toxicity and highlight their potential as effective anti-inflammatory agents [ABSTRACT FROM AUTHOR]

The crosslinked polystyrene microspheres (PS) matrix was prepared by suspension polymerization, and chloroacetylated polystyrene microspheres (PS-Cl) were obtained by Friedel-Crafts reaction on the surface.The effects of solvent type, acylation reagent amount, catalyst amount, reaction time and solvent amount on PS-Cl load and chloroacetyl chloride coversion rate were investigated.The products were characterized by FTIR, SEM and PSD, and the thermal stability of the products was investigated. The results showed that the average particle size of polystyrene microspheres were 63.24 μm. The highest loading capacity of PS-Cl microspheres was 4.350 6 mmol/g and the conversion rate of chloroacetyl chloride was 57.13 % under the reaction conditions of PS, acylation reagent (Reg) and catalyst AlCl3 molar ratio of 1∶1.2∶1.2 (1.00 g of PS microspheres), reaction time of 4 h and solvent dichloromethane of 20 mL. [ABSTRACT FROM AUTHOR]

In this work, homogeneous, thin-film proton exchange membranes (PEMs) with superior proton conductivities and high methanol rejection were fabricated via a facile synthesis procedure. Sulfonated polyether ether ketone (sPEEK) was crosslinked via a Friedel–Crafts reaction by α,α′-dichloro-p-xylene, a non-hazardous and hydrophobic compound. PEMs with varying crosslinking and sulfonation degrees were fabricated to overcome the traditional trade-off between methanol rejection and proton conductivity. The sulfonation of PEEK at 60 °C for 24 h resulted in a sulfonation degree of 56%. Those highly sulfonated backbones, in combination with a low membrane thickness (ca. 20 µm), resulted in proton conductivities superior to Nafion 117. Furthermore, X-ray photoelectron spectroscopy proved it was possible to control the crosslinking degree via the crosslinking time and temperature. The PEMs with the highest crosslinking degree showed better methanol rejection compared to the commercial benchmark. The introduction of the crosslinker created hydrophobic membrane sections, which reduced the water and methanol uptake. Subsequently, the membrane became denser due to the crosslinking, hindering the solute permeation. Those two effects led to lower methanol crossovers. This study proved the successful fabrication of PEMs overcoming the trade-off between proton conductivity and methanol rejection, following a facile procedure using low-cost and non-hazardous materials. [ABSTRACT FROM AUTHOR]

The synthesis of indoles and their derivatives, more specifically bis(indolyl)methanes (BIMs), has been an area of great interest in organic chemistry, since these compounds exhibit a range of interesting biological and pharmacological properties. BIMs are naturally found in cruciferous vegetables and have been shown to be effective antifungal, antibacterial, anti-inflammatory, and even anticancer agents. Traditionally, the synthesis of BIMs has been achieved upon the acidic condensation of an aldehyde with indole, utilizing a variety of protic or Lewis acids. However, due to the increased environmental awareness of our society, the focus has shifted towards the development of greener synthetic technologies, like photocatalysis, organocatalysis, the use of nanocatalysts, microwave irradiation, ball milling, continuous flow, and many more. Thus, in this review, we summarize the medicinal properties of BIMs and the developed BIM synthetic protocols, utilizing the reaction between aldehydes with indoles, while focusing on the more environmentally friendly methods developed over the years.

The Hock cleavage, which is compatible with tandem processes, was applied to the synthesis of 1-aryltetralines through a one-pot transformation from readily available benzyl(prenyl)malonate substrates. After the photooxygenation of the prenyl moiety, the resulting hydroperoxide was directly engaged in a Hock cleavage by adding a Lewis acid. The presence of an aromatic nucleophile in the reaction mixture and that of a benzyl moiety on the substrate resulted in tandem Friedel–Crafts reactions to form the 1-aryltetraline products. These compounds share a close analogy to the cyclolignan natural products. Experimental observations and a DFT study support the involvement of an aldehyde intermediate during the Friedel–Crafts reactions, rather than an oxocarbenium.

Herein, we describe a copper‐catalyzed sequential C(sp2)−H/C(sp3)−H annulation of indoles with propargylic alcohols for the synthesis of diversely functionalized hydrobenzo[b]carbazole scaffolds. The reaction involves a Friedel‐Crafts addition, 1,5‐H shift, 6π electrocyclization, and dearomatization‐aromatization cascade. Importantly, this is a report of the use of 2‐(diarylmethyl)indoles as three‐carbon synthons in a (3+3) annulation reaction involving C(sp3)−H indole functionalization under oxidant‐free conditions. [ABSTRACT FROM AUTHOR]

This article explores the bioinspired total syntheses of gymnothelignans, which are natural products found in Gymnotheca chinensis plants. These gymnothelignans have unique structures and show moderate cytotoxic activities against cancer cells. The article presents two proposed pathways for their synthesis and discusses the total syntheses of eupodienone-type gymnothelignans. It also provides insights into their biogenetic relationships through chemical synthesis. The authors hope to initiate further discussions on this topic and provide information about their research interests. [Extracted from the article]

The catalytic influences of boric acid have been introduced on dual Friedel‐Crafts reaction between arylamines and aldehydes to install the Csp3‐center that leads to the formation of di‐ or tri‐substituted methanes. The described reaction conditions have directed the transformation to favor the para‐para substitution pattern to deliver the major products rather than the corresponding ortho‐para functionalization process. The devised transformation was examined by DFT calculation, which shows the favorable activation energy of transition states (TS) for the generation of highly substituted molecular scaffolds. The method was applicable over diversely substituted aldehydes and arylamines to afford the final products in excellent yields (60‐92 %) and selectivity. The proposed mechanism is supported by suitable control experiments, GC‐MS studies, and DFT calculations. [ABSTRACT FROM AUTHOR]