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Comprehensive Summary: Cross‐electrophile couplings (XEC), a crucial subset of cross‐coupling reactions, center on the formation of robust C—C bonds through the union of two electrophiles. Usually, such reactions have primarily been catalyzed by transition metals. However, with the steady advancements in photochemical and electrochemical technologies, XEC reactions have significantly progressed and broadened their scope, allowing for the utilization of a wider array of tolerable functional groups, thus revealing vast application prospects. This review aims to systematically summarize the current prevalent types of electrophiles and delve into their specific application examples within XEC reactions involving electrophiles with identical functional groups. Specifically, XECs between the same type of halides have received considerable attention, whereas carboxylic acids and alcohols are still in the early stages of investigation. Furthermore, certain other common electrophiles remain unexplored in this context. Moreover, this review underscores the remarkable contributions of photochemistry and electrochemistry in the field of XEC reactions, aiming to provide valuable insights and inspiration for researchers. Also, this review hopes to spark further interest in XEC reactions, thereby fueling the continuous development and advancement of this exciting area of research. Key Scientists: Since the 1960s, advancements in the XEC reaction have been substantial, driven primarily by the application of transition metal catalysts. In this area, many distinguished scientists have contributed their wisdom and efforts. Particularly noteworthy is that, during the systematic study of XEC reactions with the identical functional groups, in 2016, MacMillan achieved a photocatalytic XEC reaction between aryl bromides and alkyl bromides; in 2020, Weix successfully realized a nickel‐catalyzed XEC reaction between aryl chlorides and alkyl chlorides. Concurrently, contributions from researchers such as Mei, Wolf, Sevov, Lin, Shen, Browne, Zhang, and Qiu have expanded the scope of XEC reactions to various halides. By 2022, MacMillan and Baran achieved a significant milestone in the XEC between carboxylic acids, further broadening the scope of research in this area. Also, advancements in the XEC of alcohols have been noted, with researchers including Weix, Lian, Tu, and Stahl conducting pioneering work and successfully executing the XEC of protective groups. It is foreseen that the ongoing research endeavors will primarily concentrate on the expansion of diverse electrophiles. [ABSTRACT FROM AUTHOR]

Pairing transition metals and heavier tetrylenes (Si, Ge, Sn, Pb) holds great potential for cooperative bond activation and catalysis. In this work, we investigate the reactivity of a low-coordinate Pt(0)/Ge(II) system that emerges from the reaction between the monoligated platinum(0) precursor [(PMe2ArDipp2)Pt(olefin)] with germylene dimer [ArDipp2GeCl]2 (where ArDipp2 = C6H3−2,6-(C6H3−2,6-iPr2)2). The resulting complex reveals ability for cooperative bond activation. Stoichiometric reactions with dihydrogen, water, methanol, ammonia and alkynes unveil the formation of Pt(II)-germyl compounds, characterized by distinct isomeric forms, whose flexibility derives from the particularly low-coordination. We explore its catalytic potential in the hydrodehalogenation of aliphatic, aromatic and main-group halides under dihydrogen atmosphere using both thermal and photochemical conditions, demonstrating promising conversions even for more challenging alkyl chlorides. Pairing transition metals and heavier tetrylenes holds potential for cooperative bond activation. Here, the authors investigate the reactivity of a low-coordinate Pt(0)/Ge(II) system that emerges from the reaction between a monoligated platinum(0) precursor with a germylene dimer and explore its application as a hydrodehalogenation catalyst. [ABSTRACT FROM AUTHOR]

Dichloromethane, as a readily available and inexpensive C1 synthon is proposed as a powerful building block for cyclopropanation of alkenes under mild conditions. Herein, we report a highly efficient and versatile dual photoredox system, involving a nickel aminopyridine coordination complex and a photocatalyst, for the cyclopropanation of aromatic olefins using dichloromethane, under visible‐light irradiation. The cyclopropanation protocol has been successfully applied at gram scale. Mechanistic studies suggest a Ni(II) pyridyl radical complex as the key intermediate for the homolytic cleavage of the Csp3−Cl bond, generating a chloromethyl radical that is captured by the olefin coupling partner. Our findings also highlight the versatility of this methodology. By directing the radical/polar crossover process, we were able to selectively drive the reaction towards either the formation of cyclopropyl derivatives or the corresponding non‐cyclic alkyl chloride products. The methodology also successfully apply to geminal dichloroalkanes, including the formation of spiro[2,2] compounds. Moreover, our methodology extends to the synthesis of deuterium‐labelled cyclopropanes, demonstrating its utility in isotopic labelling and broadening its applicability in chemical synthesis and drug development. [ABSTRACT FROM AUTHOR]

A new radical relay approach for the efficient construction of alkylsulfonated indolo[2,1-a]isoquinoline-6(5H)-ones in moderate to good yields under mild conditions via SO2 insertion/Smiles rearrangement/intramolecular cyclization is developed. This approach utilizes 4-alkyl substituted Hantzsch esters as alkyl radical sources and further undergoes in situ SO2 insertion to obtain alkylsulfonyl radical species, which avoids the use of unstable alkyl sulfonyl chlorides and highly toxic sulfonyl hydrazides. Additionally, this method for the direct assembly of alkylsulfonated polycyclic molecule skeletons displays high chemical selectivity, broad substrate scope, and step-economy. [ABSTRACT FROM AUTHOR]

Alkyl chlorides are a class of versatile building blocks widely used to generate C(sp3)‐rich scaffolds through transformation such as nucleophilic substitution, radical addition reactions and metal‐catalyzed cross‐coupling processes. Despite their utility in the synthesis of high‐value functional molecules, distinct methods for the preparation of alkyl chlorides are underrepresented. Here, we report a visible‐light‐mediated dual catalysis strategy for the modular synthesis of highly functionalized and structurally diverse arylated chloroalkanes via the coupling of diaryliodonium salts, alkenes and potassium chloride. A distinctive aspect of this transformation is a ligand‐design‐driven approach for the development of a copper(II)‐based atom‐transfer catalyst that enables the aryl‐chlorination of electron‐poor alkenes, complementing its iron(III)‐based counterpart that accommodates non‐activated aliphatic alkenes and styrene derivatives. The complementarity of the two dual catalytic systems allows the efficient aryl‐chlorination of alkenes bearing different stereo‐electronic properties and a broad range of functional groups, maximizing the structural diversity of the 1‐aryl, 2‐chloroalkane products. [ABSTRACT FROM AUTHOR]

Low‐valent chromium catalysts are cheap and less toxic compared to other transition metal catalysts. Here in, we reported a ligand‐free chromium(III)‐catalyzed manganese reductive cross‐coupling of unactivated alkyl electrophiles, such as alkyl sulfonates and alkyl chlorides, with trisulfide dioxides as thiolation agents to form carbon−sulfur bonds. The powerful method featured ample substrate scope and wide functional group tolerance, constructing a large number of unsymmetrical disulfides under simple conditions. [ABSTRACT FROM AUTHOR]

The hydrochlorination of alkenes has been extensively studied in research and is commonly featured in organic chemistry textbooks as an exemplification of the Markovnikov rule. However, the application of this reaction is typically limited to specific alkenes, such as highly substituted ones, styrenes, or strained systems. Conversely, monosubstituted or 1,2-disubstituted alkenes do not readily react with HCl gas or solutions of HCl gas at practical rates. The challenges associated with hydrochlorination reactions for these "non-activated" alkenes have spurred considerable research efforts over the past 30 years, which constitute the primary focus of this review. The discussion begins with classical polar hydrochlorinations, followed by metal-promoted radical hydrochlorinations, and concludes with a brief overview of recent anti-Markovnikov hydrochlorinations.

1-Alkyl-3-methylimidazolium ionic liquids are common cellulose solvents and biomass pretreatment agents, while beta-irradiation ("e-beaming") is often used to decrease the recalcitrance of biomass towards hydrolysis or saccharification. Aiming at the general goal of elucidating the interaction between lignocellulosics, imidazolium-based ionic liquids, and beta-irradiation, we studied the effect of beta-irradiation on the pure ILs 1-ethyl-3-methylimidazolium and 1-butyl-3-methylimidazolium, both as chloride and acetate. Contrary to the expectation of inertness, irradiation caused degradation of the ILs, which was proportional to irradiation dosage, i.e., to irradiation time and intensity. At a dosage of 2400 kGy, 0.2% (2000 ppm) of the IL were chemically altered. The main degradation pathway is the formation of imidazole and N-methylimidazole with concomitant dealkylation. The cleaved-off alkyl groups, apparently in cationic form, react with the anions present, accounting for the formation of alkyl chlorides and alkyl acetates from the chloride ILs and acetate ILs, respectively. A second, minor pathway comprises the degradation of the imidazole ring under conversion of the C2-unit from the former C4-C5 moiety into ethylenediamine and reaction of the C1-unit from the former C2 with the IL anions. Because of the non-neglible byproduct formation, the degradation of the ILs upon beta-irradiation and possible side reactions of the resulting byproducts need to be kept in mind for all setups that involve beta-irradiation and imidazolium ILs simultaneously. [ABSTRACT FROM AUTHOR]

Atom transfer radical addition (ATRA) of halogenated compounds with alkenes is well established but primary alkyl chlorides are understudied because of the difficult C−Cl bond activation. In this paper, we show that TONs of 61 can be achieved in the ATRA of ethyl chloroacetate onto styrene with [Cp*Ru(Cl)2(PPh3)] and 1,1′‐azobis(cyclohexanecarbonitrile) (ACHN) as a radical initiator, representing a three‐fold improvement compared to previous reports. New catalyst precursors of the type [Cp*Ru(Cl)2(PR3)] were synthesized and tested (R=Me, Et, Cy, Ph, p‐CF3C6H4 and p‐MeOC6H4). The kinetic reaction profiles were studied using in situ ATR−FTIR spectroscopy. Among these complexes, [Cp*Ru(Cl)2(PPh3)] gave the best yields while [Cp*Ru(Cl)2(PMe3)] showed the highest rate. While rates correlate with redox potentials (electronics), our investigation reveals that substrate sterics are important for the overall yield. Density functional theory calculations suggest an open‐shell singlet pathway, where polymerization is kinetically disfavored, explaining the selectivity towards ATRA products. [ABSTRACT FROM AUTHOR]

Functionalized primary alkyl chlorides are precursors to a plethora of scaffolds but their access from chemical feedstocks remains challenging. Herein, we report a concise dual Ni/photoredox catalytic protocol for regioselective chlorocarbonylation of unactivated alkenes that enables rapid access to β‐keto primary chlorides. The catalytic process features an extensive substrate scope, scalability and functional group tolerance. The Ni/photocatalytic Cl⋅ generation and subsequent cross‐coupling is implicated for the process based on the control experiments and DFT study. The synthetic utility of the protocol has been further corroborated through functionalization of complex substrates and modifications of the product. [ABSTRACT FROM AUTHOR]

The enormous and widespread use of organoboronic acids has prompted the development of innovative synthetic methodologies to meet the demands on structural diversity and functional group tolerance. The existing photoinduced defunctionalization radical borylation, typically focused on the conversion of one C-X bond (X= Br, I, or other leaving group) into only one C-B bond. Herein, we disclose a divergent radical dechloroborylation reaction enabled by dinuclear gold catalysis with visible light irradiation. A wide range of structurally diverse alkyl boronic, α-chloroboronic, and gem-diboronic esters can be synthesized in moderate to good yields (up to 92%). Its synthetic robustness is further demonstrated on a preparative scale and applied to late-stage diversification of complex molecules. The process hinges on a C-Cl bond relay activation in readily available gem-dichloroalkanes through inner-sphere electron transfer, overcoming the redox potential limits of unreactive alkyl chlorides. The widespread use of organoboronic acids has prompted the development of synthetic methodologies to meet the demands on structural diversity and functional group tolerance. Herein, the authors disclose a divergent radical dechloroborylation reaction enabled by dinuclear gold catalysis with visible light irradiation. [ABSTRACT FROM AUTHOR]

This article provides an overview of recent advancements in transition-metal-catalyzed Sonogashira cross-coupling reactions of alkyl electrophiles. It discusses the challenges associated with coupling nonactivated alkyl electrophiles and highlights three catalytic systems that have been developed to address these challenges. The article also mentions the development of enantioselective Sonogashira reactions using copper catalysts with chiral ligands. The challenges and future directions in this field are also discussed. [Extracted from the article]

The traditional method for the preparation of alkylboronic esters involves transition metal catalysis or transition metal‐free methods relying on single electron transfer. Each method relies on the suitable choice of catalyst or electron transfer mediator. In this study, we have developed a new method for the synthesis of alkylboronic esters from alkyl chlorides and diboron(4) compounds, without the need for additional metal or non‐metal catalysts. We discovered that under 400 nm visible light irradiation, alkyl chlorides can be activated in the presence of bis(neopentyl glycolato)diboron and an alkoxide base to form alkyl radical intermediates, which then react with diboron(4) compounds, resulting in high yields of alkylboronic esters. The reaction is applicable to both primary and secondary alkyl chlorides. The simplicity of operation and the broad substrate scope of this method make it practical for the synthesis of valuable alkylboronic ester intermediates. [ABSTRACT FROM AUTHOR]

This article explores the use of copper complexes as catalysts for radical reactions in organic synthesis. It emphasizes the importance of metal-catalyzed processes in drug development and highlights copper's suitability as a catalyst due to its low cost and availability. The role of ligands in stabilizing copper complexes and influencing their reactivity is also discussed. The authors specifically focus on copper-catalyzed radical cross-coupling reactions and direct alkylation of electron-rich heteroarenes. The article provides detailed information on reaction mechanisms and the broad scope and efficiency of these reactions. Additionally, the authors explore the use of copper complexes in photoinduced radical reactions as an alternative to traditional photoredox catalysts. The challenges and future prospects of copper catalysis in radical chemistry are also addressed, with an emphasis on the advantages of using copper complexes and their potential for developing new radical reactions and processes. [Extracted from the article]

Comprehensive Summary: A metal‐free, green, and sustainable functionalization of unactivated alkyl sp3 C—H bonds is reported using iodine(III) as a feasible dehydrogenation agent under visible light or KBr, and alkyl chlorides, bromides, alcohols, and ketones could be constructed by addition of different coupling reagents. Cheap and safe iodobenzene diacetate was used to form a radical to activate the alkyl sp3 C—H bond in a highly efficient manner, which can construct different alkylation products by adding corresponding coupling reagents. [ABSTRACT FROM AUTHOR]

This document provides information on the synthesis of a COVID-19 therapeutic drug called Ensitrelvir. The addition of LiCl (lithium chloride) was found to facilitate the generation of lithium triazinolate, which improved the yield and selectivity of the N-alkylation process. The use of LiCl and Et3N (triethylamine) also simplified the work-up operation and allowed for the use of a cheaper and more readily available base. The method was effective for various electrophiles, and further investigation is being conducted on the substrate scope of nucleophiles. The document also includes information on the physical and spectroscopic properties of the synthesized compounds, as well as acknowledgments and additional supporting information. [Extracted from the article]

An outline is given of how to split the n-dimensional space of torsion angles occurring in flexible (bio-)polymers (like alkanes, nucleic acids, or proteins, for instance) into n one-dimensional potential curves. Forthcoming applications will focus on the "protein folding problem," beginning with polyglycine. Context: In accordance with Euler's topology rules, molecules are considered to be composed of "vertices" (atoms, ligands, bonding sites, functional groups, and bigger fragments). Following Hückel, each vertex is represented by only one basis function. Starting from the "monofocal" hydrids CH 4 , NH 3 , OH 2 , FH, and SiH 4 , PH 3 , SH 2 , ClH as anchor units, "chemionic" Hamiltonians (of individual "chemion ensembles" and proportional nuclear charges) are constructed recursively, together with an appropriate basis set for the first five (normal) alkanes and some related oligomers like primary alcohols, alkyl amines, and alkyl chlorides. Methods: Standard methods ("Restricted Hartree-Fock RHF" and "Full Configuration Interaction FCI") are used to solve the various stationary Schrödinger equations. Two software packages are indispensable: "SMILES" for integral evaluations over Slater-type orbitals (STO), and "Numerical Recipes" for matrix diagonalizations and inversions. While managing with only two-center repulsion integrals, "implicit multi-center integrations" lead us to the non-empirical fundament of Hoffmann's "Extended-Hückel Theory." [ABSTRACT FROM AUTHOR]

This article discusses the synthesis and characterization of several compounds, including piperazinone derivatives. The compounds are described in terms of their chemical structures, physical properties, and spectroscopic data. The authors provide detailed information about the synthesis procedure, yield, and characterization techniques used. This information can be useful for researchers studying these specific compounds or related topics. The authors acknowledge the University of Belgrade, Faculty of Pharmacy for their support, and additional supporting information is available online. [Extracted from the article]

Reactions of unactivated alkyl chlorides under mild and sustainable conditions are rare compared to those of alkyl bromides or iodides. As a result, synthetic methods capable of modifying the vast chemical space of chloroalkane reagents, wastes, and materials are limited. We report the cobalt‐catalyzed reductive addition of unactivated alkyl chlorides to conjugated alkenes. Co‐catalyzed activation of alkyl chlorides is performed under electroreductive conditions, and the resulting reactions constitute formal alkyl‐alkyl bond formation. In addition to developing an operationally simple methodology, detailed mechanistic studies provide insights into the elementary steps of a proposed catalytic cycle. In particular, we propose a switch in the mechanism of C−Cl bond activation from nucleophilic substitution to halogen atom abstraction, which is critical for efficiently generating alkyl radicals. These mechanistic insights were leveraged in designing ligands that enable couplings of primary, secondary, and tertiary alkyl chlorides. [ABSTRACT FROM AUTHOR]

The synthesis of CpFe(CO)2ECOCH2CO2R [E = S (1), Se (2); R = Me (a), Et (b)] was achieved by treating (µ-Ex)[CpFe(CO)2]2 (E = S, x = 2–4, Se, x = 1) with alkyl malonyl chlorides at ambient temperature. The synthesized compounds were characterized by elemental analysis, FT-IR, 1H and 13C NMR spectroscopy as well as with UV–Vis spectroscopic techniques. The molecular structures of 1a and 2a were determined by single crystal X-ray diffraction studies and reveal that the two compounds are monomeric in the solid state with the iron center located in a distorted octahedral environment. [ABSTRACT FROM AUTHOR]

In this paper, we report an alternative approach to the targeted -oxyallylboronate: a copper-catalyzed 1,4-acylboration of , -unsaturated esters with B SB 2 sb pin SB 2 sb and pivalic anhydride is described (Scheme 1c). H SB 2 sb O SB 2 sb under acetate buffer conditions [11] furnished the corresponding allylic alcohol B 4 b with maintenance of the ketene acetal moiety, which can be a good synthetic handle for further manipulations. The ligand gave a large impact on the yield and I E/Z i selectivity, with the electron-withdrawing monodentate P(3,5-(CF SB 3 sb ) SB 2 sb C SB 6 sb H SB 3 sb ) SB 3 sb proving to be best (entries 1-5). Keywords: allylboronate; borylation; conjugate addition; copper; stereoselectivity EN allylboronate borylation conjugate addition copper stereoselectivity 2205 2209 5 10/31/23 20231127 NES 231127 Graph Allylborons constitute an important class of organoboron compounds in modern synthetic organic chemistry because they enable the chemo- and stereoselective allylation of organic molecules, after which the resulting allyl moiety can be transformable with high diversity. [Extracted from the article]

This document provides an overview of recent developments in the synthesis and transformation of ¿-haloboron compounds, which are important building blocks in organic synthesis. The authors discuss various methods for preparing ¿-haloboron compounds, such as the Matteson homologation reaction and hydrozirconation. They also highlight the use of nickel catalysts for the asymmetric transformation of racemic ¿-haloboronates. The document concludes by discussing a new method for constructing ¿-haloboronates through a deoxygenative difunctionalization of carbonyls. The authors emphasize the need for further research in this area and share their own findings in the field. [Extracted from the article]

A method has been developed for the selective C(2)H alkylation of (benz)oxazoles with tertiary alkyl chlorides and alkyl bromides under visible light-induced (460 nm) catalysis with the Pd(PPh3)4/[Bu4N]I system in N,N-dimethylacetamide. The tetraalkylammonium salt has a significant promoting effect on the reaction, which seems to be based on the stabilization of nanosized palladium species in the catalytic system. [ABSTRACT FROM AUTHOR]

The coagulation ability of organic and inorganic quaternary ammonium salts is assessed comparatively. It is found that the replacement of a hydrogen atom in ammonium chloride with an alkyl radical decreases the consumption of the coagulation agent. The best results are achieved when tetraethylammonium chloride is used as a coagulant. The resulting rubbers and vulcanizates meet the requirements according to their main indicators. [ABSTRACT FROM AUTHOR]

Decarboxylative halogenation reactions of alkyl carboxylic acids are highly valuable reactions for the synthesis of structurally diverse alkyl halides. However, many reported protocols rely on stoichiometric strong oxidants or highly electrophilic halogenating agents. Herein, we describe visible‐light photoredox‐catalyzed decarboxylative halogenation reactions of N‐hydroxyphthalimide‐activated carboxylic acids that avoid stoichiometric oxidants and use inexpensive inorganic halide salts as the halogenating agents. Bromination with lithium bromide proceeds under simple, transition‐metal‐free conditions using an organic photoredox catalyst and no other additives, whereas dual photoredox‐copper catalysis is required for chlorination with lithium chloride. The mild conditions display excellent functional‐group tolerance, which is demonstrated through the transformation of a diverse range of structurally complex carboxylic acid containing natural products into the corresponding alkyl bromides and chlorides. In addition, we show the generality of the dual photoredox‐copper‐catalyzed decarboxylative functionalization with inorganic salts by extension to thiocyanation with potassium thiocyanide, which was applied to the synthesis of complex alkyl thiocyanates. [ABSTRACT FROM AUTHOR]

In recent years, the activation of unactivated alkyl chlorides through light-induced processes has emerged as a promising field in radical chemistry, and has led to new transformations in organic synthesis. Direct utilization of alkyl chlorides as C(sp3)-hybridized electrophiles enables the facile construction of carbon–carbon and carbon–heteroatom bonds. Furthermore, recent studies in medicinal chemistry indicate that their presence is associated with high levels of success in clinical trials. This review summarizes the recent advances in the photoinduced activation of unactivated alkyl chlorides and discusses the mechanistic aspects underlying these reactions. We anticipate that this review will serve as a valuable resource for researchers in the field of unactivated chemical bond functionalization, and inspire considerable developments in organic chemistry, drug synthesis, materials science and other related disciplines. [ABSTRACT FROM AUTHOR]

Polystyrene (PS) is one of the least recycled large‐volume commodity plastics due to bulkiness of foam products and associated contaminants. PS recycling is also severely hampered by the lack of financial incentive, limited versatility, and poor selectivity of existing methods. To this end, herein we report a thermochemical recycling strategy of "degradation‐upcycling" to synthesize a library of high‐value aromatic chemicals from PS wastes with high versatility and selectivity. Two cascade reactions are selected to first degrade PS to benzene under mild temperatures, followed by the derivatization thereof utilizing a variety of acyl/alkyl and sulfinyl chloride additives. To demonstrate the versatility, nine ketones and sulfides of cosmetic and pharmaceutical relevance were prepared, including propiophenone, benzophenone, and diphenyl sulfide. The approach is also amenable to sophisticated upcycling reaction designs and can produce desired products stepwise. The facile and versatile approach will provide a scalable and profitable methodology for upcycling PS waste into value‐added chemicals. [ABSTRACT FROM AUTHOR]

[34] The reaction with enantioenriched -methylbenzylboronic acid pinacol ester resulted in a 56:44 diastereomeric mixture of alcohol products B 48 b , the same diastereomeric mixture as was observed using racemic alkylboronic ester. [3][5][6] This short review details our laboratory's examination of reactions using benzylboronic acid pinacol ester and secondary and tertiary benzylboronic esters as nucleophiles. Keywords: boron; benzylation; Lewis base; copper; boronate EN boron benzylation Lewis base copper boronate 2639 2647 9 08/17/23 20230901 NES 230901 Graph 1 Introduction Organoboranes have found great utility in organic synthesis. Specifically, substrates containing esters and amides to the ketone were found to be compatible under these reaction conditions with no reaction being observed at the ester or amide carbonyl carbon ( B 25 b and B 26 b ). [Extracted from the article]

In the present manuscript, we reported the first visible‐light‐enabled direct C3−H alkylation/arylation of quinoxalin‐2(1H)‐ones with unactivated alkyl/aryl chlorides under metal‐free conditions. A wide range of unactivated alkyl and aryl chlorides containing different functionalities are coupled with a variety of quinoxalin‐2(1H)‐one derivatives under mild reaction conditions to afford the C3‐alkyl/aryl substituted quinoxalin‐2(1H)‐ones in moderate to good yields. [ABSTRACT FROM AUTHOR]

Selective oxidation of ethylene to ethylene oxide (EO) is performed industrially over catalysts comprised of silver particles supported on α‐Al2O3. In addition to various oxy‐anion and alkali promotors, alkyl chloride species ("chloride moderators") are continuously introduced into commercial reactors. The effect and usage of chloride moderators is a key requirement for industrial ethylene epoxidation catalysts to reach optimal selectivity. While not an exhaustive review, the aim of this perspective is to provide guidance to academic researchers on the operation of EO catalysts under commercially relevant conditions with particular focus on the importance of performance optimization. [ABSTRACT FROM AUTHOR]

A catalytic amount of CsI enables dual concurrent activation of poorly reactive perfluoroalkoxide and alkyl halides, especially alkyl chlorides, leading to the formation of diverse perfluoroalkoxylated organic compounds. Installation of perfluoroalkoxy groups by this methodology is cost-effective, circumventing the need for over-stoichiometric cesium or silver salts. This methodology also provides high functional group compatibility and tolerance of sterically hindered substrates. [ABSTRACT FROM AUTHOR]

IR (C SB 2 sb H SB 2 sb Cl SB 2 sb ): 1675, 1620 cm SP -1 sp . This had also been observed for deoxyhalogenation reactions using Ph SB 3 sb PX SB 2 sb reagents in the presence of triethylamine. This transformation is already well-documented: COCl SB 2 sb , PCl SB 3 sb , OPCl SB 3 sb , acetyl and oxalyl chlorides, triphenylphosphine-derived reagents Ph SB 3 sb PX SB 2 sb , Ph SB 3 sb P/CX SB 4 sb and the Vilsmeier reagent have been successfully used. 3-Chloro-6-allylcyclohex-2-en-1-one (21a) 1518 The title product was prepared using 0.183 g (1.4 mmol) of TMCE ( B 2a b ) and 0.189 g (1.2 mmol) of 4-allylcyclohexan-1,3-dione in CH SB 2 sb Cl SB 2 sb for 5 h at rt. [Extracted from the article]

We describe a nickel-catalyzed three-component sulfonylation of readily available non-activated alkyl chlorides. A wide range of alkyl aryl sulfones can be synthesized from alkyl chlorides, aryl boronic acids, and potassium metabisulfite, a cheap, efficient, and commercially available SO2 source under simple and easy-to-handle reaction conditions. High selectivity can be achieved with a slight excess of phenylboronic acid and a sulfur dioxide source. [ABSTRACT FROM AUTHOR]

With the instability and alternative reactive modes of alkyl sulfenyl chlorides making the synthesis of a broad range of alkyl allenyl sulfoxides via the [2,3]-sigmatropic rearrangement difficult, alternative sources of electrophilic sulfur were explored. Examination of various N-sulfanylimides revealed that thiosuccinimides are a viable sulfur source for the synthesis of alkyl allenyl sulfoxides via the [2,3]-sigmatropic rearrangement. With the optimized conditions of excess propargyl alcohol and potassium carbonate in chloroform at 50 °C, a variety of alkyl allenyl sulfoxides were synthesized in fair to good yields (21–73%, 21 examples). Additionally, butyn-1,4-diols can be selectively monofunctionalized with a large excess of diol and stoichiometric triethylamine in THF at room temperature to form 1-hydroxyalkyl allenyl sulfoxides (26–71%). These diols can also be bis-functionalized to form 2,3-disubstitued dienes (53–66%) via two separate [2,3]-sigmatropic rearrangements. The formation of alkyl allenyl sulfoxides was also found to be selective for less substitution at the propargyl position (3:1–100:0 ratio) as shown in direct competition experiments. Trimethylsilylethyl thiosuccinimides were among the highest yielding of the thioimides. The sulfenate chemistry of select allenyl sulfoxides can be successfully performed. [ABSTRACT FROM AUTHOR]

Novel strategy for acid chlorides formation that do not use carboxylic acids is particularly attractive in chemical synthesis but remains challenging. Herein, we reported the development of a highly effective Pd-catalyzed hydrochlorocarbonylation of alkenes with CO for the formation of alkyl acid chlorides. Chlorosilane and AcOH were found as a mild HCl source for the reaction. The reaction shows broad substrate scope and produces both branched and linear alkyl acid chlorides in good to high yields upon different ligands and solvents. Cooperating with follow-up acylation reactions, the Pd-catalyzed hydrochlorocarbonylation offers a complementary platform for the synthesis of diverse carbonyl compounds from alkenes. Mechanistic investigations suggested that the reaction proceeded though a palladium hydride pathway, and CO prompted reductive elimination of the acyl-Pd-Cl intermediate. Acid chloride formation is generally limited to the chlorination of carboxylic acids. Here, the authors report a palladium-catalyzed regiodivergent hydrochlorocarbonylation of alkenes for the synthesis of various alkyl acid chlorides. [ABSTRACT FROM AUTHOR]

In compliance with Article 31 of Regulation (EC) No 178/2002, EFSA received a mandate from the European Commission to prepare a statement on the risk assessment related to the presence of benzalkonium chloride (mixture of alkylbenzyldimethylammonium chlorides with alkyl chain lengths of C8, C10, C12, C14, C16 and C18) (BAC), didecyldimethylammonium chloride (mixture of alkyl‐quaternary ammonium salts with alkyl chain lengths of C8, C10 and C12) (DDAC) and chlorates in fish and fish products. Within EFSA's annual chemical data collection, EFSA collected monitoring data for the residues of BAC, DDAC and chlorates from EU Member States, Iceland and Norway performed a statistical evaluation, providing estimated residue values for each substance in/on fish and fish products, at the percentile appropriate for the number of the available samples. Based on the information collected, EFSA performed an acute and chronic exposure assessment for EU consumers for BAC, DDAC and chlorates at the lower‐bound, medium‐bound and upper‐bound scenarios resulting from the consumption of fish and fish products. EFSA did not identify potential consumer health risks associated to residues of the substances found in fish and fish products. [ABSTRACT FROM AUTHOR]

We describe here the development of a visible light driven nickel carbonylation catalyst. The combination of the large bite‐angle Xantphos ligand with nickel(0) generates a catalyst capable of activating alkyl halides toward carbonylation at ambient temperature in the presence of blue light irradiation, and the reductive elimination of high energy acid chloride products. Unlike classical carbonylations, where the coordination of carbon monoxide inhibits the reactivity of earth abundant nickel catalysts, a CO‐associated nickel is found to be the active catalyst in the reaction. Coupling the build‐up of acid chlorides with nucleophile addition can be used to access various amides, esters and thioesters, including those of sterically encumbered substrates or with metal‐reactive functionalities. [ABSTRACT FROM AUTHOR]

Palladium‐catalyzed couplings of silicon enolates with aryl electrophiles are of great synthetic utility, but often limited to expensive bromide substrates. A comparative experimental study confirmed that none of the established ligand systems allows to couple inexpensive aryl chlorides with α‐trimethylsilyl alkylnitriles. In contrast, ylide functionalized phosphines (YPhos) led to encouraging results. A statistical model was developed that correlates the reaction yields with ligand features. It was employed to predict catalyst structures with superior performance. With this cheminformatics approach, YPhos ligands were tailored specifically to the demands of Hiyama couplings. The newly synthesized ligands displayed record‐setting activities, enabling the elusive coupling of aryl chlorides with α‐trimethylsilyl alkyl nitriles. The preparative utility of the catalyst system was demonstrated by the synthesis of pharmaceutically meaningful α‐aryl alkylnitriles, α‐arylcarbonyls and biaryls. [ABSTRACT FROM AUTHOR]

Biomass derivable epichlorohydrin undergoes ring‐opening copolymerization with either succinic or itaconic anhydride (both biosourcable) under standard laboratory conditions using metal‐based or an entirely organic initiator to form highly functionalized, low molecular weight polyesters. The linear polyesters obtained from epichlorohydrin and itaconic anhydride contain both alkyl chlorides and α,β‐unsaturated esters and can be crosslinked to form insoluble resins by treatment with di‐ to tetra‐functional amines and thiols. Crosslinking with amines predominately occurs through the alkyl chlorides whilst crosslinking with thiols occurs through the α,β‐unsaturated esters allowing the synthesis of insoluble polyester derived resins with complementary and controllable functionalities. [ABSTRACT FROM AUTHOR]

The first rhodium‐catalyzed formylation of non‐activated alkyl chlorides with syn gas (H2/CO) allows to produce aldehydes in high yields (25 examples). A catalyst optimization study revealed Rh(acac)(CO)2 in the presence of 1,3‐bisdiphenylphosphinopropane (DPPP) as the most active catalyst system for this transformation. Key for the success of the reaction is the addition of sodium iodide (NaI) to the reaction system, which leads to the formation of activated alkyl iodides as intermediates. Depending on the reaction conditions, either the linear or branched aldehydes can be preferentially obtained, which is explained by a different mechanism. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A general and straightforward strategy for the synthesis of thioester‐substituted oxindoles via a palladium‐catalyzed thiocarbonylative cyclization process has been developed. With sulfonyl chlorides as promising sulfur source, a wide range of thioester‐substituted oxindoles were obtained in moderate to high yields. Both aryl and alkyl sulfonyl chlorides were well tolerated, and Mo(CO)6 played a dual role as both a CO source and a reductant in this approach. [ABSTRACT FROM AUTHOR]

In recent years, porous materials have been extensively studied by the scientific community owing to their excellent properties and potential use in many different areas, such as gas separation and adsorption. Hyper-crosslinked porous polymers (HCLPs) have gained attention because of their high surface area and porosity, low density, high chemical and thermal stability, and excellent adsorption capabilities in comparison to other porous materials. Herein, we report the synthesis, characterization, and gas (particularly CO2) adsorption performance of a series of novel styrene-based HCLPs. The materials were prepared in two steps. The first step involved radical copolymerization of divinylbenzene (DVB) and 4-vinylbenzyl chloride (VBC), a non-porous gel-type polymer, which was then modified by hyper-crosslinking, generating micropores with a high surface area of more than 700 m2 g−1. In the following step, the polymer was impregnated with various polyamines that reacted with residual alkyl chloride groups on the pore walls. This impregnation substantially improved the CO2/N2 and CO2/CH4 adsorption selectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • The continuous flow microreactor were used for the synthesis of chlorides. • The fluid model was proposed based on kinetic parameters. • Catalytic experiments validated the reliability of the fluid model. • The chloride achieved yields of up to ∼98 % with excellent reusability. The efficient and safe synthesis of chlorides is attractive in pharmaceutical chemicals yet presents challenges. Herein, a novel route has been developed for the conversion of alcohols into the corresponding alkyl chlorides in continuous flow microreactor. Meanwhile, the system utilizes deep eutectic solvents (DESs) hydrochloride solutions (DESs/HCl) as both solvents and catalysts for this reaction. The results suggest that the premixed mode continuous flow microreactor using DESs/HCl can significantly improve the harsh reaction conditions in the synthesis reaction of chlorides. Furthermore, tuning the HCl concentration under 383 K and 30 min conditions significantly increased the yields of n -Butanol chloride and Benzyl chloride to 86 % and 98 %, respectively. This work shows the great application potential of the continuous flow microreactor combined with DESs/HCl to convert alcohols into corresponding alkyl chlorides or aryl chlorides. Besides, the fluid model and HCl absorption kinetics were established based on the calculated diffusion coefficients (D R), Damköhler number (Da), Bodenstein number (Bo), residence time (τ), and experimental results. The flow model of the mixture of DESs/HCl and alcohols in the microreactor was a plug flow, which is beneficial for improving the efficiency of this reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel and straightforward procedure for the synthesis of thioester-substituted indolo[2,1-a]isoquinolines。 • A nickel-catalyzed cyclization/thiocarbonylation procedure. • Both aryl and alkyl sulfonyl chlorides were transformed. • Mo(CO) 6 has been used as convenient CO source and reductant. • A wide range of thioester-substituted indolo[2,1-a]isoquinolines were obtained in moderate to high yields. A novel and straightforward procedure for the synthesis of thioester-substituted indolo[2,1- a ]isoquinolines has been established. The reaction proceed via nickel-catalyzed cyclization/thiocarbonylation from alkene-tethered indoles and sulfonyl chlorides. Very good compatibility toward a wide range of functional groups was observed, both aryl and alkyl sulfonyl chlorides were well tolerated. With Mo(CO) 6 as a convenient and solid CO surrogate, and by using sulfonyl chloride as an abundant and cheap sulfur source, a variety of thioester-substituted indolo[2,1- a ]isoquinolines were obtained in moderate to high yields. [ABSTRACT FROM AUTHOR]