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The use of fluoroalkoxy groups, such as trifluoromethoxy and 2,2,2‐trifluoroethoxy groups, in pharmaceutical and agrochemical development has increased dramatically in recent years. However, hexafluoroisopropoxy groups have remained significantly under‐represented, presumably due to limited synthetic methods for accessing this substituent in good yields. Herein, we report a mild, photochemical nucleophilic aromatic substitution (SNAr) approach for the synthesis of hexafluoroisopropyl aryl ethers from unactivated and abundant aryl halides. Notably, aryl chloride and bromide functionality are efficiently engaged by this methodology in addition to the traditional aryl fluoride nucleofuge. This method provided access to a diverse array of hexafluoroisopropyl aryl ethers, including multiple examples of late‐stage functionalization of active pharmaceutical ingredients. A simple flow system was adapted for 10x scale‐up, maintaining good yield for the reaction. Initial mechanistic studies indicate single electron oxidation of the arene as a key step in product formation. [ABSTRACT FROM AUTHOR]

The carbon-carbon bond formation reactions have always been interesting for scientists because of their wide range of uses in organic chemistry. The Suzuki-Miyaura reaction is a famous reaction for the C-C bond formation. The Suzuki-Miyaura reaction is applied to synthesize a wide range of pharmaceutical and biological compounds. In this research, a Cu (II) Salen complex supported on KCC-1 (Cu (II) Salen complex@KCC-1) has been synthesized and characterized for the C-C bond formation reaction. The synthesized catalyst was determined to be an effective heterogeneous catalyst for the coupling reaction of Suzuki-Miyaura. The synthesized catalyst was characterized via XRD, FT-IR, TEM, and EDX, and the organic compound was identification with melting-point, FT-IR, and 1H NMR techniques. Cu (II) Salen @ KCC-1 complex can be separated and reused simply in the reaction mixture and reused several consecutive runs without significantly reducing the catalyst's performance. To identify each product, FT-IR, 1H NMR, and melting point techniques were applied. [ABSTRACT FROM AUTHOR]

Halogen bonding permeates many areas of chemistry. A wide range of halogen-bond donors including neutral, cationic, monovalent, and hypervalent have been developed and studied. In this work we used density functional theory (DFT), natural bond orbital (NBO) theory, and quantum theory of atoms in molecules (QTAIM) to analyze aryl halogen-bond donors that are neutral, cationic, monovalent and hypervalent and in each series we include the halogens Cl, Br, I, and At. Within this diverse set of halogen-bond donors, we have found trends that relate halogen bond length with the van der Waals radii of the halogen and the non-covalent or partial covalency of the halogen bond. We have also developed a model to calculate ΔG of halogen-bond formation by the linear combination of the % p-orbital character on the halogen and energy of the σ-hole on the halogen-bond donor.

Abstract The palladium anchored to BisPyP@bilayer-SiO2@NMP organic–inorganic hybrid was employed as an effective and recyclable organometallic catalyst in Suzuki and Stille C–C coupling reactions. The structure of this magnetic nanocatalyst was determined using various techniques such as SEM, TEM, FT-IR, EDS, ICP-OES, VSM, N2 adsorption–desorption isotherms, XRD, and TGA. In both of the mentioned coupling paths, the yields of the products were very favorable and ranged from 90 to 98%. Also, they had significant features compared to previous reports, such as very short reaction time (5–15 and 7–20 min respectively in the Suzuki and Stille reactions), easy work-up, broad substrate scope, ease of separation of the catalyst using a magnet, suitable reproducibility of the catalyst in 6 runs, heterogeneous nature of the catalyst and not washing it during consecutive runs with confirmation of hot filtration and ICP-OES methods.

The palladium anchored to BisPyP@bilayer-SiO2@NMP organic–inorganic hybrid was employed as an effective and recyclable organometallic catalyst in Suzuki and Stille C–C coupling reactions. The structure of this magnetic nanocatalyst was determined using various techniques such as SEM, TEM, FT-IR, EDS, ICP-OES, VSM, N2 adsorption–desorption isotherms, XRD, and TGA. In both of the mentioned coupling paths, the yields of the products were very favorable and ranged from 90 to 98%. Also, they had significant features compared to previous reports, such as very short reaction time (5–15 and 7–20 min respectively in the Suzuki and Stille reactions), easy work-up, broad substrate scope, ease of separation of the catalyst using a magnet, suitable reproducibility of the catalyst in 6 runs, heterogeneous nature of the catalyst and not washing it during consecutive runs with confirmation of hot filtration and ICP-OES methods. [ABSTRACT FROM AUTHOR]

Aniline compounds are important organic intermediates and basic chemical raw materials, widely applied in research fields such as pharmaceuticals, agrochemicals, dyes, and functional materials. The development of efficient and versatile synthesis of aniline derivatives is one of the research hotspots that have been attracting much attention. In the past few decades, the study of transition metal-catalyzed synthesis of aniline derivatives from aryl halides has attracted significant attention from chemists due to its advantages of broad substrate applicability, good functional group compatibility, and high reaction selectivity. This review summarizes the research progress in transition metal-catalyzed synthesis of aniline derivatives from aryl halides, including: (1) palladium-catalyzed synthesis of aniline derivatives from aryl halides; (2) copper-catalyzed synthesis of aniline derivatives from aryl halides; (3) nickelcatalyzed synthesis of aniline derivatives from aryl halides. [ABSTRACT FROM AUTHOR]

Two new ferrocene based molecules S,S′‐bis(4‐aminophenyl)ferrocene‐1,1'‐bis(carbothioate) (I) and S,S′‐bis(3‐aminophenyl)ferrocene‐1,1'‐bis(carbothioate) (II) have been synthesized via a thioester linkage. The prepared compounds have been successfully applied as ligands for the CuI catalyzed Sonogashira coupling reaction. The ligands are highly effective for the Csp2−Csp coupling between alkyne and iodobenzene and bromobenzene. Corresponding 1,2‐disubstituted alkynes could be synthesized from both aryl and alkyl alkynes in high yield by using catalytic amount of CuI in presence of bis(3‐aminophenyl)ferrocene derivative in dioxane at 50 °C. [ABSTRACT FROM AUTHOR]

Aryl and alkenyl halides are widely used as key intermediates in organic synthesis, particularly for the formation of organometallic reagents or as radical precursors. They are also found in pharmaceutical and agrochemical ingredients. In this work, the synthesis of aryl and alkenyl halides from the corresponding fluorosulfonates using commercially available ruthenium catalysts is reported. Notably, this is the first conversion of phenols to aryl halides that is efficient with chloride, bromide, and iodide. Fluorosulfonates are readily prepared using sulfuryl fluoride (SO2F2) and less expensive substitutes for triflates. Although aryl fluorosulfonates and their reactions are well known, this is the first report of an efficient coupling of alkenyl fluorosulfonates. To finish, it was demonstrated, by means of representative examples, that the reaction is possible in a one‐pot process, starting directly from phenol or aldehyde. [ABSTRACT FROM AUTHOR]

The reactions involving aryl radicals is an efficient strategy for the synthesis of a wide variety of important molecules. We have highlighted here recent developments on the generation of aryl radicals from various substrates by visible light mediated photocatalysis and their reactions with different substrates to produce a library of arylated and het-arylated compounds. These reactions are performed at room temperature using LED bulbs. Thus, this strategy is green involving less energy.

This paper describes the synthesis and catalytic testing of a palladium complex with a 5-membered chelating [N,O] ligand, derived from the condensation of 2,6-diisopropylphenyl aniline and maple lactone. This catalyst was active towards the Suzuki-Miyaura cross-coupling reaction, and its activity was optimised through the selection of base, solvent, catalytic loading and temperature. The optimised conditions are mild, occurring at room temperature and over a short timescale (1 h) using solvents considered to be 'green'. A substrate scope was then carried out in which the catalyst showed good activity towards aryl bromides with electron-withdrawing groups. The catalyst was active across a broad scope of electron-donating and high-withdrawing aryl bromides with the highest activity shown for weak electron-withdrawing groups. The catalyst also showed good activity across a range of boronic acids and pinacol esters with even boronic acids featuring strong electron-withdrawing groups showing some activity. The catalyst was also a capable catalyst for the cross-coupling of aryl chlorides and phenylboronic acid. This more challenging reaction requires slightly elevated temperatures over a longer timescale but is still considered mild compared to similar examples in the literature. [ABSTRACT FROM AUTHOR]

Abstract Cu2O supported on polyaniline (PANI) encapsulating CuFe2O4 was found to be highly efficient, magnetically separable and recyclable heterogeneous catalyst for the C-N cross-coupling reaction of arylhalides with amines. It was successfully synthesized and characterized using FT-IR, VSM, TGA, TEM, SEM, EDX, and XRD. The applicability of PANI/nano-CuFe2O4/Cu2O catalyst was considered in the C-N cross-coupling reaction of aryl halides with alkyl and aryl amines in good yields without using external ligands or additives as promoters. Notably, the PANI/nano-CuFe2O4/Cu2O catalyst was separated from the reaction by using an external magnet and recycled for seven runs without significant loss of catalytic activity. [ABSTRACT FROM AUTHOR]

This review summarizes recent applications of copper or copper-based compounds as a nonprecious metal catalyst in N-nucleophiles-based dehalogenation (DH) reactions of halogenated aromatic compounds (Ar-Xs). Cu-catalyzed DH enables the production of corresponding nonhalogenated aromatic products (Ar-Nu), which are much more biodegradable and can be mineralized during aerobic wastewater treatment or which are principally further applicable. Based on available knowledge, the developed Cu-based DH methods enable the utilization of amines for effective cleavage of aryl-halogen bonds in organic solvents or even in an aqueous solution. [ABSTRACT FROM AUTHOR]

A silica-coated magnetically separable Schiff-base palladium nanocatalyst was developed. Amorphous silica was used to encapsulate the magnetic Fe3O4 and an organic amine functionality was added to the silica surface. The amino group was treated with 1, 10-phenanthroline-2,9-dicarboxaldehyde to produce a Schiff-base, which was then treated with palladium to produce the silica coated magnetic Schiff-base palladium nanocatalyst. The palladium nanocatalyst was fully characterized using several spectroscopic techniques. The HR-SEM image of silica coated Fe3O4 revealed a globular shape with a diameter of 145 nm, along with this the average palladium nanoparticle size was 3.5 ± 0.6 nm. The successful functionalization and the appearances of the palladium species as a magnetic catalyst was confirmed by FT-IR and XRD analysis. The palladium nanocatalyst was successfully applied for the construction of CC bonds via Suzuki-Miyaura reaction. With a variety of organoboronic acids, the catalyst displayed great performance for electron-poor and electron-rich aryl halides, resulting in excellent yields of the corresponding cross-coupling products. The magnetic catalyst was retrieved from the reaction vial using an external strong magnet, and it was reused seven times without a significant drop in the production of the corresponding biaryl product.

The common access to forming CN bond is the copper‐catalyzed Ullmann‐type reaction. The relatively expensive and easily oxidized copper(I) is usually used in the reaction. Our group discovered that the "vitamin C/glycerol" reduction system could convert cheap and stable CuO to active low valence state copper species, as measured via X‐ray photoelectron spectroscopy (XPS), to promote the CN coupling reaction. In particular, 2‐phenylindole, pyrrolo[1,2‐a]quinoxaline, 1,2,4‐triazole and 4‐amino‐7H‐pyrrolo[2,3‐d]pyrimidine derivative were obtained in the presence of CuO and reduction system "vitamin C/glycerol." This method provided a simple and cost‐effective approach to the preparation of N‐arylation products. [ABSTRACT FROM AUTHOR]

Heck cross-coupling reaction (HCR) is one of the few transition metal catalyzed C C bond-forming reactions, which has been considered as the most effective, direct, and atom economical synthetic method using various catalytic systems. Heck reaction is widely employed in numerous syntheses including preparation of pharmaceutical and biologically active compounds, agrochemicals, natural products, fine chemicals, etc. Commonly, Pd-based catalysts have been used in HCR. In recent decades, the application of biopolymers as natural and effective supports has received attention due to their being cost effective, abundance, and non-toxicity. In fact, recent studies demonstrated that biopolymer-based catalysts had high sorption capacities, chelating activities, versatility, and stability, which make them potentially applicable as green materials (supports) in HCR. These catalytic systems present high stability and recyclability after several cycles of reaction. This review aims at providing an overview of the current progresses made towards the application of various polysaccharide and gelatin-supported metal catalysts in HCR in recent years. Natural polymers such as starch, gum, pectin, chitin, chitosan, cellulose, alginate and gelatin have been used as natural supports for metal-based catalysts in HCR. Diverse aspects of the reactions, different methods of preparation and application of polysaccharide and gelatin-based catalysts and their reusability have been reviewed. Current trends, challenges and future prospects exploiting the sustainable applications of chitin, chitosan, starch, cellulose, pectin, alginate, gelatin and gum based (nano)catalysts for the Heck coupling reactions, are highlighted. [Display omitted] • Advances in Heck coupling reactions by biopolymer-based catalysts are described. • Synthetic methods for attaining biopolymer-based catalysts are highlighted. • Catalytic activity of chitin, chitosan, starch, cellulose, pectin, alginate, gelatin and gum based catalysts are presented. • Mechanistic details are provided for Heck coupling reactions using biopolymer-based catalysts. • Future challenges pertaining to Heck coupling reactions using biopolymer-based catalysts are discussed. [ABSTRACT FROM AUTHOR]

An efficient nickel‐catalyzed regioselective hydroarylation of 1,3‐dienes with aryl halides and a silane has been developed, affording a range of allylic arenes in good to excellent yields under mild conditions. This method exhibits broad substrate scope, and excellent functional group tolerance. Late‐stage modification of complex architectures was demonstrated. [ABSTRACT FROM AUTHOR]

We herein disclose the first Ni-catalyzed Hiyama coupling of aryl halides with vinylsilanes. This protocol uses cheap, nontoxic, and stable vinyltrimethoxysilane as the vinyl donor, proceeds under mild and ligand-free conditions, furnishing a diverse variety of styrene derivatives in high yields with excellent functional group compatibility. [ABSTRACT FROM AUTHOR]

Halogenated and polyhalogenated aromatic compounds are known for their toxicity and effect on human health and the environment. These aromatic hydrocarbons have been widely used in pesticides, flame retardants, pharmaceuticals, and other industrial chemicals. The substitution of halogen atoms of aromatic halides by hydrogen atoms in the presence of a metal catalyst is an important organic transformation and is known as a catalytic hydro‐dehalogenation reaction. It is an important technique used for the treatment of halogenated industrial waste. Herein, we investigated the comparative hydro‐dehalogenation of aryl halides in the presence of Pd‐gC3N4 catalyst using various hydrogen transfer sources in an eco‐friendly manner. We also investigated the advantage of using sodium hypophosphite (NaH2PO2) as a hydrogen source for hydro‐dehalogenation in comparison to alkali metal formates. For hydro‐dehalogenation of 1 mmol of aryl halide, 2 equivalents of NaH2PO2 are used while 4 equivalents of KHCO2 are required in the presence of 3.8 wt % of Pd metal catalyst. The Pd‐GCN catalyst was characterized by various microscopic and spectral techniques such as PXRD, FTIR, SEM, TEM, XPS, and TGA, etc. A gram scale reaction was performed to analyze the industrial potential of the proposed catalytic system. Finally, the recyclability of Pd‐GCN was found excellent and the catalyst could run multiple cycles with sustained activity. [ABSTRACT FROM AUTHOR]

A MCM-41-supported palladium (II) α-diimine complex has been synthesized via anchoring of 3-chloropropyltriethoxysilane on mesoporous silica MCM-41, followed by grafting α-diimine ligand through the covalent approach to bind with Pd(II) ion. Different analytical technique such FT-IR, TGA, low angle powder XRD, SEM, TEM, ICP-MS and N2 sorption were used to characterize the complex. The complex serves as a highly active and recyclable catalyst for Suzuki-Miyaura coupling reaction affording a variety of biaryls with good yields.

Halogen bonding permeates many areas of chemistry. A wide range of halogen-bond donors including neutral, cationic, monovalent, and hypervalent have been developed and studied. In this work we used density functional theory (DFT), natural bond orbital (NBO) theory, and quantum theory of atoms in molecules (QTAIM) to analyze aryl halogen-bond donors that are neutral, cationic, monovalent and hypervalent and in each series we include the halogens Cl, Br, I, and At. Within this diverse set of halogen-bond donors, we have found trends that relate halogen bond length with the van der Waals radii of the halogen and the non-covalent or partial covalency of the halogen bond. We have also developed a model to calculate Δ G of halogen-bond formation by the linear combination of the % p-orbital character on the halogen and energy of the σ-hole on the halogen-bond donor., (Copyright © 2024, Javaly et al.)

A practical and mild synthetic strategy has been investigated for the ligand free arylation of aromatic amines and nitrogen heterocycles using nano-Fe3O4@Cellulose-NH2-CuI as a recoverable catalyst based on magnetic cellulose.ّ Firstly, the cellulose was functionalized with amine groups and then was composite with nano-magnetic particles and Copper(I) iodide. The development of efficient methodology for formation C-N bond is one of the most important reactions in organic chemistry. The nano-Fe3O4@Cellulose-NH2-CuI as a cheap, heterogeneous and recyclable catalyst produced the corresponding compounds in high yields. The recyclability, high yields, short reaction times and simple procedure of reaction are merits of this new methodology.

A new free radical/palladium cooperative catalyzed formylation of aryl halides with glyoxylic acid as the formyl source under oxygen conditions has been developed. Various aromatic and heteroaromatic aldehydes were produced in medium to good yields. [ABSTRACT FROM AUTHOR]

A ligand‐free, CuI‐catalyzed protocol was developed for the one‐step preparation of Michael adducts of aromatic thiols in high yields by reacting a mixture of an aryl halide and an electron‐deficient alkene with sodium iso‐propyl xanthogenate. [ABSTRACT FROM AUTHOR]

An efficient methodology has been developed for C−N cross‐coupling reaction between aryl halide and amine using a catalytic system comprised of CuI and N,N‐dimethyl amino pyridine (DMAP). Coupling reactions were carried out in DMSO at 120 °C in presence of 5 mol% CuI, 20 mol% DMAP and 2.5 equivalent of KOH. Addition of DMAP was found to be beneficial in accelerating the rate of reaction significantly. Both aryl iodides and aryl bromides could be successfully coupled with different primary and secondary amines to furnish the desired cross‐coupling product in high yield. A copper complex [Cu(DMAP)4I]I made by combining CuI and DMAP was found to produce superior result for the Buchwlad‐Hartwig cross coupling reaction. The use of 2 mol% of the copper complex is sufficient to produce high yield of the product. [ABSTRACT FROM AUTHOR]

The Mizoroki–Heck (MH) reaction involving aryl halides with various acrylates and acrylamides has been studied using air and moisture‐stable imidazolium‐based palladate pre‐catalysts. These pre‐catalysts can be converted into Pd‐NHC species (NHC = N‐heterocyclic carbene) under catalytic conditions and are capable of facilitating the Mizoroki–Heck reaction of aryl halides with various acrylates. The effects of solvent, catalyst loading, temperature and bases on the reaction outcome have been investigated. Various coupling partners were tolerated under the optimal reaction conditions catalyzed by palladate 1, [SIPr·H][Pd(η3‐2‐Me‐allyl)Cl2]. The efficiency of the optimized synthetic methodology was tested on various aryl halides and substituted acrylates as well as acrylamides. The MH reaction yielded the coupled products in good to excellent isolated yields (up to 98%). [ABSTRACT FROM AUTHOR]

A palladium (II) complex immobilized onto nanosilica(Pd-imine@nanoSiO 2) has been developed and evaluated as a highly efficient, retrievable catalyst for carbon-carbon triple bond activation reactions between aryl halides and terminal alkynes. Nanosilica has been derived from rice husk by simple and eco-compatible methodology. The catalyst has been extensively characterized by techniques such as FT-IR, UV–vis, powder XRD, XPS, SEM-EDX, thermogravimetric analysis, BET surface area measurement. The catalyst can be reused for five consecutive runs without compromising much with the activity. Easy preparation, its long shelf life, air-stability, wide substrate scope, 'in water' reactions, easy separability and good recyclability make it an ideal system for Sonogashira cross-coupling reaction. Moreover, various alkyne substrates were efficiently cross-coupled with a broad range of aryl iodides and aryl bromides to afford diaryl alkynes, providing improved yields with low catalyst loading in water. This protocol is also suitable for aliphatic alkynes. Image 1 • Rice husk derived nanosilica supported Pd-imine@nanoSiO 2 catalyst can be synthesized easily. • This is the first example of a nanosilica anchored Pd catalyst for Sonogashira cross-coupling reaction in aqueous medium in copper free condition. • Activate both aryl iodides and aryl bromides to afford diaryl alkynes. This protocol was also suitable for aliphatic alkynes. • The catalyst can be reused for five consecutive cycles without profound loss in activity. [ABSTRACT FROM AUTHOR]

A new magnetically recoverable silica-based nickel(II) nanocatalyst was synthesized by a simple cost-effective procedure, which was characterized by TEM, SEM, XRD, VSM analysis, and FT-IR spectrophotometry. The catalytic activity of the prepared Ni(II) nanocatalyst was tested in two complementary reactions: C–N Chan–Lam cross-coupling of phenylboronic acid with aryl amines and C–C Suzuki–Miyaura cross-coupling reaction of phenylboronic acid with aryl halides. The catalyst was easily recovered by magnetic separation and reused for five times. It demonstrated better catalytic activity in the C–N Chan–Lam reaction compared to C–C Suzuki–Miyaura reaction. Ease of recovery and reusability up to five cycles without noticeable loss of performance in the C–N cross-coupling reaction make the present protocol beneficial both industrially and environmentally. In this paper, a new magnetically recoverable silica-based nickel(II) nanocatalyst was synthesized and applied in two complementary reactions: C–C Suzuki–Miyaura reaction and C–N Chan–Lam reaction. The difference in catalytic activity makes it possible to use this catalyst for cases that are prone to both reactions and selectively create the desired product. [ABSTRACT FROM AUTHOR]

A combination of CuI with oxalic diamide is a powerful catalytic system for cross-coupling reaction of thiols with aryl bromides and chlorides. It is important to note that unactivated aryl chorides are coupled smoothly with aryl- and alkyl thiols to give the corresponding thioethers in good to excellent yields for the first time. [ABSTRACT FROM AUTHOR]

A convenient and efficient synthesis of sulfones from sulfinates and aryl halides was developed. The reaction occurred under UV irradiation without transition metal catalyst or photocatalyst. A radical pathway via single‐electron transfer (SET) of electron donor‐acceptor (EDA) complex was proposed based on UV‐vis spectroscopy, radical inhibiting and trapping experiments. [ABSTRACT FROM AUTHOR]