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Designing of eco-friendly, low cost, and thermally stable stabilizing/supporting agents are always desired for production of catalyst systems which provide good catalytic performance in organic reactions. In this study, a novel, green, and efficient stabilizer containing chitosan/Co3O4 microspheres (CS/Co3O4) was developed. Palladium nanoparticles (Pd NPs) were then successfully immobilized on CS/Co3O4 as a heterogeneous nanocatalyst (Pd NPs/CS/Co3O4). Characterization of the designed materials were performed by FT-IR, TEM, FE-SEM, XRD, and EDS and it was determined that Pd NPs formed as approximately 20 nm. Catalytic behavior of Pd NPs/CS/Co3O4 was investigated in the production of different substituted benzonitriles via aryl halide cyanation. Catalytic studies indicate that electron-rich or poor aromatic halides were smoothly cyanated with good reaction yields by Pd NPs/CS/Co3O4 nanocatalyst by using K4[Fe(CN)6] as the cyanating agent. Moreover, it was found that Pd NPs/CS/Co3O4 nanocatalyst provided not only good reaction yields and but also good recovery/reusability for six times in the aryl halide cyanations. This paper displays that Pd NPs/CS/Co3O4 nanocatalyst has a great catalytic and recycling potential for aryl halide cyanations.

The Sonogashira cross coupling reaction is an applied method for preparation of diarylethyne compounds from readily available aryl halide derivatives and phenyl acetylene. The coupling reaction using nickel complex of N,N′-Bis(2-hydroxyethyl)ethylenediamine onto core shell graphene oxide (GO@SiO2-BHED-Ni) as a catalyst was studied in this research. This heterogonous catalyst showed good thermal stability, highly efficiency and recyclability in the reaction. Moreover, the catalyst is simply separated and can be reused several times without significant loss of catalytic activity. A wide range of aryl halides was coupled successfully under palladium and phosphine free conditions. The use of this catalyst led to the formation of substituted aromatic alkynes in excellent yields and short reaction times.

The article highlights the synthesis of two different fullerene core star-like dyad materials: fullerene-phenylene-alt-thiophene (FPTP) and fullerene-acetylene terminated phenylene-alt-thiophene (FAPTP). PTP was prepared by Suzuki cross coupling reaction, whereas, the APTP was synthesized by Suzuki-Sonogashira cross coupling reaction. Synthesis of FAPTP dyad is a unique example of extension of Suzuki-Sonogashira cross coupling reaction where bromo-fullerene behaves as an aryl halide and APTP acts as an acetylene terminated conjugated system. Number of addends attached to fullerene core was estimated by using thermal methods (TGA & DSC). Both the optical (2.57–2.59 eV) and electrochemical band gaps (1.91–2.29 eV) indicate lower values for dyads compared to polymers. Low HOMO values (−5.79 to −5.86 eV) and nearly overlapping cyclic voltammograms at different scan rates suggest good air and electrochemical stability for both polymers and dyads materials. Photovoltaic properties and energy level diagram reveal its electron-hole (carrier) transport mechanism and potential for solar cells application.

Transition metal copper (II) Schiff base composite (Cu NH2 GO) was synthesized using functionalized graphene oxide with (3-aminopropyl) methoxysilane (APTMS). X-ray diffraction, FTIR spectroscopy and thermogravimetric analyses ascertained the incorporation of the copper (II) Schiff base on the functionalized graphene oxide. Scanning electron microscopy and TEM evidences further confirmed the surface morphology of the composite. Catalytic activity study indicated that the synthesized Cu NH2 GO was active for cross-coupling of aryl halide with phenylboronic acid. Above 84% (4-Iodobenzonitrile) biphenyl conversion could be achieved using Cu NH2 GO catalyst in the C C coupling reaction.

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 Csingle bondC 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. yes

A Cu (II) Salen complex supported on KCC-1 (Cu(II) Salen complex@KCC-1) has been synthesized and characterized via XRD, FT-IR, TEM, and EDX. The synthesized catalyst was determined to be an effective heterogeneous catalyst for the coupling reaction of Suzuki-Miyaura. Cu (II) Salen @ KCC-1 complex can be separated and reused simply in the reaction mixture and reused several consecutive runs without a significant reduction in the performance of the catalyst. The development of a KCC-1-supported Cu catalyst is anticipating to be a promising system for carrying out heterogeneous catalytic reactions.

Diaryl selenide is the main drug candidate today. An efficient, easy and ligand free cross-coupling reaction of aryl halide and diaryl diselenide was carried out by as-prepared copper sulfide functionalized carbon (Cu2S@C) catalyst. Cu2S@C catalyst was developed using novel tri-cationic ionic liquid (IL) as a precursor and sulfur source. Catalyst found to having rich content of heteroatoms (S and N) by EDX and Elemental mapping characterization techniques. Effective utilization of catalyst was carried out by synthesis of variety of aryl selenide in excellent yield from readily halides and diaryl diselenides. Active centers in the catalyst provide efficient activation for crosscoupling reaction. Moreover, catalyst where easily reusable for three times without any obvious loss in catalytic activity.

The synthesis, reactivity, spectroscopic characterization and catalytic activities of a series of Pd(II) complexes bearing the chelating ligands 2-(4,5-dihydrothiazol-2-yl)aniline (2) and 2-(4,5-dihydro-1H-imidazol-2-yl)aniline (3) are reported. The reactions of 2 with [Pd(COD)Cl2] in 1:1 and 1:2 (ligand into metal and metal into ligand) molar ratios afforded the mononuclear complexes, PdCl2{κ2−N,S − 2−(4,5-dihydrothiazol-2-yl)aniline} (4), Pd{κ2−N,N’−2−(4,5-dihydrothiazol-2-yl)aniline}2 (5) and Pd{κ12−N,N’−κ22−N,S − 2−(4,5-dihydrothiazol-2-yl)aniline}2 (6), respectively, in good yields. The neutral mononuclear palladium complexes PdCl2{κ2−N,N’−(4,5-dihydro-1H-imidazol-2-yl)aniline} (7) and Pd{κ2−N,N’−2−(4,5-dihydro-1H-imidazol-2-yl)aniline}2 (8) were synthesized using [Pd(COD)Cl2] with appropriate molar ratios. The palladium complexes 4–8 were evaluated for their catalytic activities in base assisted cross coupling reactions between acid chlorides and aryl halide with boronic acids. The complex 4 was found to be an efficient catalyst for producing unsymmetrical ketones (TOF = 19.8 min−1) while complex 7 was effective for making biaryls (TOF = 19.8 min−1).

The present manuscript elicits the use of novel magnetically separable silica coated copper (Cu-ACP-Am-Fe3O4@SiO2) as a heterogeneous nanocatalyst for the Huisgen 1,3-dipolar cycloaddition reaction of alkyl or aryl halide, sodium azide and terminal alkyne, which provide a series of 1,4-disubstituted-1,2,3-triazoles. The catalyst was characterized by various physicochemical techniques such as Powder X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-Ray Spectroscopy(EDS), Thermogravimetric analysis (TGA-DSC), X-ray Photoelectron spectroscopy (XPS) and Vibrational sampling magnetometer (VSM). The acquisition of this nanocatalyst is also exemplified by employing reusability test and recycling of synthesized catalyst was achieved multiple times just by sequestering with an external magnet. It is noteworthy that the key-features like mild reaction conditions, simple work-up, High turnover number (TON), high turnover frequency (TOF), no use of hazardous organic solvents, easy recovery and reusability of the catalyst makes the present protocol more fascinating from an environmental and economic point of view.

A novel redox-driven method to synthesize Pd-γ-Fe 2 O 3 nanocomposite from Fe 3 O 4 and PdCl 2 under modified hydrothermal technique has been developed. The synthesized nanocomposite was characterized by XRD, FT-IR, XPS, FESEM, TEM and EDX to understand the composition as well as morphology. The Pd-γ-Fe 2 O 3 nanocomposite was found to show excellent catalytic activity towards Suzuki-Miyaura cross-coupling reactions in water without the assistance of ligands, organic solvents or phase transfer catalysts. A wide range of functional substitutions in aryl halide as well as arylboronic acid moieties is tolerated in the developed protocol. The nanocatalyst can be recovered magnetically, and reused up to six cycles without significant loss in its catalytic activity.

We report synthesis of two new palladium(II) complexes of abnormal N-heterocyclic carbene ligands. The catalytic activity of these palladium(II) complexes was examined for the decarboxylative arylation of N-methylindole-carboxylic acids. An exclusive regioselectivity and very good yields were obtained with a variety of aryl halide partners.

Four novel palladium(II) complexes coordinated by phosphorus atoms from both 3,5-disubstituted-1H-1,2,4-diazaphospholes in monodentate fashion were developed as efficient catalyst for the Mizoroki-Heck reaction of aryl halides with electron-deficient olefins. The coupling reaction of aryl halide bearig different functional groups with olefin derivatives took place and the corresponding products were isolated in good to excellent yields under optimal conditions. The procedure exhibits good functional group tolerance and wide substrate scope. This Mizoroki-Heck reaction was further achieved using Pd(OAc)2 and 3,5-di-isopropyl-1H-1,2,4-diazaphospholes as combined catalyst, which provide the convenient and alternative method in organic synthesis

Improving carbon–carbon cross-coupling reactions is an ongoing process and finding the most versatile and stable catalyst precursors has been of great interest. Ligand design has been proven to be important since it is responsible for providing electron density and steric saturation around the metal centre, thus contributing towards the stereo-electronic properties. The adamantyl moiety has been used to generate highly bulky and electron-rich ligands for application in palladium-catalysed cross-coupling reactions. Accordingly, we have prepared some Schiff-base adamantyl ligands (L1-L3) and complexed them with [PdCl2(MeCN)2] to afford the (pre)catalysts C1-C3, which were successfully applied in Mizoroki-Heck and Suzuki-Miyaura carbon–carbon cross-coupling reactions. The cross-coupling reaction products were obtained in good yields using 0.5 mol % Pd catalyst loading. C2 and C3 showed remarkable activity in the Mizoroki-Heck coupling reactions involving substrates with substituents on the olefin and aryl halide (including 4-Cl, 4-CH3, -CO2Me and -CO2Et). We also, observed that the Suzuki-Miyaura cross-coupling system was active towards challenging activated and deactivated aryl chlorides, with to up 70% conversions recorded. The mercury poisoning tests conducted revealed that the catalysts act as homogenous molecular active species in the Mizoroki-Heck reactions and act as both homogenous and heterogeneous catalysts in the Suzuki-Miyaura cross-coupling reactions.

Organic molecules with persistent room-temperature phosphorescence (RTP) have attracted considerable attention due to their broad applications, but typically suffered from low emission intensity and short lifetime. In this contribution, a twisted donor-acceptor (D-A) system by simple conjugation of acridan and aryl halide is proposed to construct efficient and ultralong RTP luminogens. The photophysical measurements and theoretical predictions demonstrate the halogenation renders simultaneous realization of large spin-orbital coupling (SOC), small energy gap between singlet/triplet excited states, and restrained non-radiative decay channel, which benefit for RTP properties. Correspondingly, the acridan derivatives realized phosphorescence quantum efficiency up to 3.2% with lifetime up to 372 ms in its crystalline state, and also exhibited distinct afterglow in heavily grinded samples. To demonstrate the potential applications, these materials were furtherly explored in information encryption and fingerprint identification. This study not only provides rare examples of efficient and long-lived phosphors based on acridan building block, but also sheds light on the inherent photophysical mechanism of RTP materials and paves a way to design highly promising RTP luminogens with a simplified structure.

Water-soluble palladium complexes were synthesized, characterized, tested as (pre)catalyst for Mizoroki-Heck carbon-carbon cross-coupling reactions in water. Cross-coupling of aryl iodides and bromides with methyl and ethyl acrylates was achieved at 140 °C. When styrene was employed as the substrate excellent conversion to trans-stilbene was observed using 5 mol% catalyst loading in the presence of TBAB. The catalysts are versatile and can couple various substrates in a non-toxic and benign solvent. After extraction of the organic product the catalyst containing aqueous layer could be recycled twice with a significant drop in the aryl halide conversion after the third recycle. No catalyst poisoning was observed in the mercury poisoning experiments with both catalysts and this proves that both catalytic systems function as molecular homogeneous catalysts.

A sulfur transfer reagent was produced in situ upon stirring a mixture of KCN and CS 2 in DMF at r.t. for 15 min, which after heating with an alkyl halide or aryl halide and CuI gave the corresponding symmetric dialkyl or diaryl disulfide, respectively, in high to excellent yields.

In this study, a one-pot two-step Pd-catalyzed reductive eliminate between acetyl naphthalene derivatives, tosylhydrazide, and aryl halide, affording substituted 1(or 2)-(1-phenylvinyl)naphthalene in moderate-to-excellent yields, was reported. Notably, solvent played a crucial role in the coupling of 1-acetyl naphthalene derivatives (toluene) or 2-acetyl naphthalene derivatives (1, 4-dioxane) as starting materials. Meanwhile, the scope of this one-pot coupling reaction was extended to 1(or 2)-naphthaldehyde substrates. Importantly, the catalytic system can be employed on a wide variety of substrates with good functional group tolerance. This protocol could also be particularly useful for the synthesis of olefins-substituents hydroxyl compounds.

This article reports a study on amino acid chelated Cu(I) catalyzed coupling of benzylamine and bromobenzene. Experiments were conducted at 80 °C with Cu(I) chelated to methionine, proline, hydroxyproline, tryptophan and tyrosine in dimethylsulfoxide (DMSO). In order to investigate kinetic effects, reaction time was restricted to 90 min. Kinetically controlled product yields over amino acid ligated Cu(I) were in the order proline > hydroxyproline > methionine > tryptophan > tyrosine. Theoretical investigation of the reaction was carried out using density functional theory method, B3LYP/6-31+G(d,p) employing the solvation model SCRF = CPCM. The effective core potential of LANL2DZ was used to model copper and bromine. Geometry optimization of the structures of reactants, intermediates and activated complexes were carried out in the solvent DMSO. It was found that the reaction over amino acid Cu(I) complexes that gave low product yields are associated with high energy barriers for aryl halide bond activation. Further, the theoretical investigation revealed that benzylamine coordinates from nitrogen and phenyl ring and it hinders the pi-cordination of bromobenzene. Therefore, in order for the reaction to progress, formation of amioacid chelated copper bromobenzene complex and subsequent activation of C Br bond must occur before the coordination of benzylamine. As the stability of the aminoacid ligated copper benzyl amine complex is much higher than the stability of the corresponding bromobenzene complex, the resting state can be taken as the amine complex. Therefore, it is proposed that benzylamine must be replaced by bromobenzene in order for the formation of aminoacid chelated copper bromobenzene complex.

A Cu2O/SiC heterogeneous catalyst was prepared via a two-step liquid-phase method using diethylene glycol as both the solvent and the reducing agent. The catalyst was characterized using X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and H2 temperature-programmed reduction. All the results indicate that Cu is present on the SiC support primarily as Cu2O. The SEM and TEM results show that cubic Cu2O nanoparticles are uniformly dispersed on the β-SiC surface. The reaction conditions, namely the temperature, reaction time, and amounts of base and catalyst used, for the Ullmann-type C–O cross-coupling reaction were optimized. A model reaction was performed using iodobenzene (14.0 mmol) and phenol (14.0 mmol) with Cu2O/SiC (5 wt% Cu) as the catalyst, Cs2CO3 (1.0 equiv.) as the base, and tetrahydrofuran as the solvent at 150 °C for 3 h; a yield of 97% was obtained and the turnover frequency (TOF) was 1136 h−1. The Cu2O/SiC catalyst has a broad substrate scope and can be used in Ullmann-type C–O cross-coupling reactions of aryl halides and phenols bearing a variety of different substituents. The catalyst also showed high activity in the Ullmann-type C–S cross-coupling of thiophenol with iodobenzene and substituted iodobenzenes; a TOF of 1186 h−1 was achieved. The recyclability of the Cu2O/SiC catalyst in the O-arylation of phenol with iodobenzene was investigated under the optimum conditions. The yield decreased from 97% to 64% after five cycles. The main reason for the decrease in the catalyst activity is loss of the active component, i.e., Cu2O.

In this work, the preparation of the palladium nanoparticles with carbon nanofibers (Pd NPs/CNFs) catalyst for the Suzuki reaction was described. In the process, palladium nanoparticles were formed in the reaction of palladium chloride and glucose. The Pd NPs/CNFs complex catalyst was prepared in subsequent calcination processes, a series of characterization revealed that the Pd NPs were well-dispersed on the surfaces of the carbon nanofibers or embedded in the carbon nanofibers. This catalyst showed high catalytic activity for the Suzuki reaction of aryl halide and aryl boronic acid in the ethanol/water (v/v = 4/3) solution, and the catalyst still had good stability after 10 cycles.

A concise and efficient approach was developed for the synthesis of mono-substituted and di-substituted pyrimidines products via palladium-catalyzed amination of chloro-substituted 5-nitropyrimidines and amines. This synthetic methodology can produce various di-substituted pyrimidines in high yields with good functional group tolerance, and provide a complementary tool for the syntheses of important intermediates of nucleosides and purines with bioactivities.

A highly efficient, less expensive and phosphine-free protocol for the Suzuki-Miyaura cross-coupling reactions of aryl halides and aryl boronic acids in iPrOH-H2O solvent under aerobic conditions has been developed. The results demonstrate that the biuret played a crucial role and making this protocol highly efficient. The Pd(OAc)2-biuret system exhibited superb catalytic activity towards the Suzuki-Miyaura cross-coupling reaction of a wide range of aryl halides with aryl boronic acids at room temperature, giving high yields even under very low catalytic loading. This system offers an attractive alternative to the existing protocols since the reaction proceeds in green solvent at room temperature with working simplicity, shorter reaction time, cost-effectiveness and provides the desired products in high yields. The effect of solvent, base as well as catalyst loading on the cross-coupling reaction of aryl halide with arylboronic acid is also described.

Efficient and concise routes to sets of novel triazolo-1,4-benzodiazepine scaffolds that are suitably functionalized for diversification at three positions to explore three-dimensional space with different substituents are described. One approach to these scaffolds features a simplified multicomponent assembly process to give an intermediate azido alkyne that undergoes a facile Huisgen dipolar cycloaddition. The triazolo-1,4-benzodiazepines thus produced may be endowed with aryl halide, secondary amino, alcohol, aldehyde or carboxylic acid groups as functional handles for orthogonal derivatization reactions. Modification of this approach enabled the facile synthesis of the related triazolo-1,4-benzodiazepin-6-ones, also bearing three functional handles. These convenient protocols were used to prepare multi-gram quantities of benzodiazepine analogs as precursors for generating compound libraries for screening campaigns.

Herein, the independent differential selectivity in the Suzuki-Miyaura reaction of two competing arylboronic acids with regard to the nature of the aryl halide (both halide and aryl moieties) was established. This pattern cannot be realized via the “textbook” mechanism of the reaction, which suggests the interaction of boron-containing species with an ArPdX intermediate (product of the aryl halide catalytic activation). The data obtained indicate the participation of two distinct palladium species in the aryl halide and arylboronic acid activations in the catalytic cycle of biaryl formation, which are in accordance with the so-called cooperative mechanism.

The mechanism of copper-catalyzed Sonogashira coupling reaction employing trans-1,2-diamino cyclohexane ligand have been investigated with Density Functional Theory (DFT) method augmented with Conductor-like Polarizable Continuum Model (CPCM) solvation model. The cross-coupling reactions could be accelerated by employing chelating diamine ligands. Thus, we considered trans-1,2-diamino cyclohexane as the ligand for our study. These coupling reactions find its applicability in the synthesis of aryl acetylenes, the precursors for the various benzofuran derivatives which are present in many biologically important compounds. Considering various reaction pathways possible, it was found that diamine ligated copper (I) acetylide was the active state of the catalyst, which on further reaction with aryl halide undergoes a concerted oxidative addition – reductive elimination process giving the cross-coupled product aryl acetylene while regenerating the active catalytic species. Unlike the Pd-catalyzed Sonogashira cross-coupling, there occurs a concerted mechanism owing to the ease of bond formation between Csp2-Csp carbon atoms and instability of a Cu (III) metal center. This shows the mechanism of copper-catalyzed cross-couplings are quite different from that of Pd catalyzed reactions. The latter usually involves individual process involving oxidative addition and reductive elimination. The presences of various functional groups on the substrate molecules have a crucial role in determining the feasibility of the reaction. Henceforth, we have investigated the electronic effects of various functional groups in the substrate molecule on the activation barrier of the cross-coupling reaction.

A systematic theoretical study has been carried out on the mechanism for the Pd-catalyzed aromatic C H activation reaction of aryl nitrile and aryl halide using cyano as the directing group. The entire catalytic cycle divides into four main processes involving C H activation, CF3COOH dissociation, oxidative addition, and reductive elimination and catalyst regeneration. The calculations indicate that the ortho carbon of the directing group cyano in aryl nitrile is activated by Pd(II) resulting in the activation of C H bond. In CF3COOH dissociation, it is found that the 5b is an essential intermediate, which facilitates the dissociation of CF3COOH ligand leading to the intermediate (η2-CF3COO−)(η2-aryl nitrile)Pd(II) (6). The Pd(II) intermediate further undergoes oxidative addition with PhI to form Pd(IV) intermediate, which proceeds by reductive elimination and catalyst regeneration to give the final product. And the reductive elimination and catalyst regeneration process can determine the reaction rate. Furthermore, the roles of additive Ag2O, directing group cyano, and solvent Trifluoroacetic acid have also been examined.

Consecutive chemo- and regio-selective decarboxylative C H arylation, followed by carbonylative C C coupling of aryl halide with isocyanide/alcohol was applied for the first time in one-step synthesis of carbonyl dibenzofurans with nanodomain cuprous oxide under aerobic condition. As a proof of concept, several novel dibenzofurans were synthesized from 2-(3-iodophenoxy)benzoic acid in good yield. The tandem protocol eliminates the use of excess catalysts, hazardous organic solvents, heavy metals like palladium or rhodium, ligands, oxidants, or external additives. More importantly, the cubic Cu(I) nanocatalyst can be recovered and recycled for three consecutive reactions without any significant loss of catalytic activity or any change in its morphology. Use of water as solvent and reusable catalyst makes the reaction environment friendly.

Aspergillosis is one of the infectious fungal diseases affecting mainly the immunocompromised patients. The scarcity of the antifungal targets has identified the importance of N-myristoyl transferase (NMT) in the regulation of fungal pathway. The dihydroquinazolinone molecules were designed on the basis of fragments responsible for binding with the target enzyme. The aryl halide, 1(a-g), aryl boronic acid and potassium carbonate were heated together in water and dioxane mixture to yield new CC bond formation in dihydroquinazolinone. The bis(triphenylphosphine)palladium(II) dichloride was used as catalyst for the CC bond formation. The synthesized series were screened for their in vitro antifungal activity against Aspergillus niger and Aspergillus fumigatus. The binding interactions of the active compound with lysozyme were explored using multiple spectroscopic studies. Molecular docking study of dihydroquinazolinones with the enzyme revealed the information regarding various binding forces involved in the interaction.

Pillar[5]arene-based 1-benzylimidazole and 1-(9-anthracenylmethyl)imidazole salts were prepared for the first time as novel class supramolecular NHC ligands. These ligands, together with PdCl 2 (CH 3 CN) 2 , were used as catalysts in the Heck coupling reactions of styrene and aryl halide derivatives. The 1-(9-anthracenylmethyl)imidazole salt exhibited better catalytic activity than the 1-benzylimidazole salt, owing to the steric bulk of the ligand. The novel pillar[5]arene-based imidazolium salt is a promising supramolecular skeleton for the construction of highly active catalysts.

Substrates bearing both a β-ketoester moiety and a (het)aryl halide structure element were dimerized to 1-naphthols and related products in the presence of catalytic amounts of CuI in isopropanol. The reaction starts with an intermolecular C-arylation, which is followed by an intramolecular condensation. The final aromatization delivers the highly substituted products with yields up to 81%.

The usefulness of the aryl halide, 4-bromopyrido-24-crown-8, in easily appending the pyrido-24-crown-8 unit onto organic frameworks to afford new dibenzylammonium receptors has been explored. Bromopyrido-24-crown-8 has been coupled with phenylboronic acid to yield 4-phenylpyrido-24-crown-8, which is shown to complex a variety of dibenzylammonium ions yielding complexes that are more stable than their dibenzo-24-crown-8 counterparts. One of these new complexes, in which a diformyl-terminated thread is bound, has been used to assemble a [2]rotaxane under thermodynamic control.

A one step, additive free protocol for ultrasound assisted synthesis of cuprous oxide (Cu 2 O) nanoparticles using glycerol as a green and sustainable solvent has been developed. The glycerol plays multiple roles in nanoparticle synthesis such as solvent, promoter, reducing agent and capping agent. It assists to control the crystal morphology of obtained Cu 2 O nanoparticles. The Cu 2 O nanoparticles were characterized with the help of XRD, TEM, HRTEM, EDS, FT-IR, XPS, BET surface area and TGA techniques. This is simple, green, inexpensive and capping agent free method for the synthesis of Cu 2 O nanoparticles. Furthermore, we showed catalytic applications of prepared Cu 2 O nanoparticles in catalysis for the coupling reaction between aryl halide and aromatic amine.

A novel method for the Cu(OAc) 2 catalyzed synthesis of unsymmetrical sulfides from triphenyltin chloride and aryl halides using S 8 as the sulfur source in PEG200 at 60–80 °C is reported. Triphenyltin chloride is capable of delivering all of its phenyl groups to the product. Also, the copper catalyzed synthesis of symmetrical diaryl sulfides from aryl halides using S 8 is described.

Baran, Talat ( Aksaray, Yazar ), In this study, Fe3O4 loaded Schiff base modified kaolin was prepared as a new support and palladium nanoparticles were anchored on it without any additional reducing agent (Pd NPs@Kao/Fe3O4/Pyr). Characterization studies demonstrated that Pd NPs@Kao/Fe3O4/Pyr was successfully designed and the size of particles was about 25 nm. Pd NPs@Kao/Fe3O4/Pyr was then utilized as catalyst in the preparation of biaryl compounds via Suzuki cross coupling reactions. Catalytic tests showed that Pd NPs@Kao/Fe3O4/Pyr acted as a highly active heterogeneous nanocatalyst in the coupling reaction of aryl iodides, bromides and chlorides containing different functional groups. Moreover, it was found that Pd NPs@Kao/Fe3O4/Pyr was successfully used in consecutive recycling tests and gave an 89% yield even after ten runs. In addition to the high catalytic behavior and reusability, Pd NPs@Kao/Fe3O4/Pyr have some advantages such as i) capability of application for various halides containing different functional groups, ii) ease of purification of final product and iii) simple work-up.

A density functional theory (DFT) study has been carried out to provide insight into the reaction mechanism of the rhodium(I)-catalyzed, P-directed selective C7 arylation of indoles with aryl halides. Our calculations suggest that it is more favorable for Rh(PPh3)2OtBu, the real catalytical species for the reaction, to initially undergo C–H activation process with the indole to generate a five − membered rhodacycle intermediate than to proceed through oxidative addition with the aryl halide to yield a Rh(III) intermediate. Subsequently, the sequential C(aryl)−C(aryl) reductive elimination and catalyst regeneration progresses produce the final 7−arylindole product. The first C–H activation process is identified as rate- and regioselectivity-determining step with an energy barrier of 26.0 kcal/mol. The underlying origins and factors responsible for C7- vs C2-, C3-, and C6-regioselectivity is revealed by noncovalent interaction analysis. The results declare that the reaction characters weak interaction and chelate effect-controlled regioselectivity. Our study provides important mechanistic insights for the dehydrogenative cross-coupling reaction between indoles with aryl halides, and guides the design of efficient Rh-based catalyst for C–H functionalization of indoles.

The present work elucidates the catalytic efficiency of palladium Schiff base complex immobilized on amine functionalized magnetic nanoparticles for Heck coupling of structurally different aryl halide/arenediazonium tetrafluoroborate with styrene/acrylate/acrylonitrile. Matsuda-Heck coupling proceeds in aqueous media at room temperature whereas Mizoroki-Heck coupling was carried out at 80 °C. Both reactions were successfully furnished with low catalyst loading. The catalyst was easily separated from reaction mixture and reused up to six times without significant loss of catalytic activity.

We synthesized a recyclable palladium ionic catalyst, Ti0.97Pd0.03O1.97, using a solution combustion method (SCM), and characterized by XRD and Rietveld refinement. The synthesized Pd ionic catalyst is stable, insensitive to moisture and air, and easy to handle. The new catalyst has exhibited a phenomenal result for the Suzuki-Miyaura cross-coupling reaction with a broad substrate scope, and the reaction proceeds in an aqueous medium. The new catalyst proved beneficial and produced excellent yields irrespective of aryl halide used in the reaction (electron-rich or electron-poor or heterocyclic compounds) and shown a turnover frequency (TOF) of 14–25 h−1 for different reactions. The catalyst was coated on a cordierite monolith (Mg2Al4Si5O18), which enhanced the applicability of the catalyst, and made the handling and recycling of the catalyst very easy. Suzuki Miyaura reaction was carried out using both Pd-powder catalysts as well as the Pd-coated honeycomb, which gave almost similar results. We have demonstrated the recyclability of Pd coated cordierite monolith and shown the superiority of the catalyst over the other Pd catalysts for the Suzuki-Miyaura reaction.

New Pd(II) complex, trans-[PdCl2L2] (1) (L = N-carbamothioylthiophene-2-carboxamide), was prepared and characterized. Its heterogeneous counterpart, trans-[PdCl2(L-SNPs)2] (2) (L-SNPs = ligand immobilized on silica nanoparticles), was also prepared through covalent modification of the ligand using silica nanoparticles and characterized. Both 1 and 2 were exploited for their catalytic activity towards condensation of phenylacetylene with aryl halides. The complexes exhibited good activity when aryl halide bears I- or Br- group. Further, catalyst 2 can be reused for four cycles.

The convenient nickel-catalyzed carbonylative coupling of aryl iodides with Ph3SnCl or Ph3SnOEt for synthesis of unsymmetrical diaryl ketones under phosphine-free condition is reported. The reaction occurs efficiently in the presence of Cr(CO)6 as an easy handling solid source of carbon monoxide at atmospheric pressure and 100 °C in DMF under air to deliver the desired ketones in high yield.

A new and simple method was developed for fabricating palladium nanoparticles (PdNPs) captured in a mesoporous monolith based on thermally induced phase separation (TIPS) method. XRD result confirmed the formation of PdNPs inside the monolith. TEM image showed that most of the captured PdNPs were in the diameter range from 5 nm to 10 nm. The monolith had relatively high specific surface area and uniform mesopore structure. To measure its catalytic efficiency, the crosslinked monolith was applied to a heterogeneous Suzuki–Miyaura reaction of aryl halide and aryl boronic acid in a water/ethanol mixture. The monolith exhibited both high catalytic performance and excellent stability for repeated use.

An easily synthesized tetraphosphine N,N,N′,N′-tetra(diphenylphosphinomethyl)-pyridine-2,6-diamine (TPPDA) in combination with PdCl2 was proved to be a highly efficient catalyst for Suzuki–Miyaura cross-coupling. This system could catalyze a variety of aryl halide substrates with a wide range of functional groups as well as heteroaryl halides. A high turnover number (TON) up to 3,350,000 was reached for 3-bromochlorobenzene.

Suzuki–Miyaura coupling reactions of arylboronic acids with aryl bromides were mediated by PdCl2 and bdppmapy (N,N-bis-(diphenylphosphanylmethyl)-2-aminopyridine) that both stabilizes and solubilizes the catalyst in predominantly ethanol as a solvent. Excellent yields for a wide variety of substrates were obtained under relatively mild conditions in this ‘green’ solvent.

Palladium chloride was successfully immobilized on MOF-253, a MOF material with un-coordinated 2,2′-bipyridine moieties, through post-synthetic modification. The coordination interaction between the 2,2′-bipyridine moieties and Pd cations in the MOF-253·PdCl2 material was demonstrated by X-ray photoelectron spectroscopy (XPS) analysis. The prepared MOF-253·0.05PdCl2 was shown to be highly active, selective, and recyclable for the Suzuki–Miyaura cross-coupling and Ullmann homocoupling of a wide range of aryl halides including electron-rich and electron-poor aryl iodides/bromides, heteroaryl iodides, and even aryl chlorides, affording the corresponding biaryl compounds in good to excellent yields under mild reaction conditions. It is suggested that the 2,2′-bipyridine moieties in MOF-253 provide electron-rich environment for Pd(II) cations, and thus facilitate the initial adsorption and insertion of aryl halides molecules to Pd active sites during the carbon–carbon coupling reactions. Moreover, MOF-253·PdCl2 showed remarkably higher activity than the homogeneous Pd(bpy)Cl2 and PdCl2(CH3CN)2, which might be due to the presence of charge transfers between adjacent ligands and metals in the MOF catalyst. The superior catalytic performances of metal ions immobilized on MOFs to their homogenous counterparts might bring new opportunities in the development of highly efficient metal catalysts combining advantages of both homogeneous and heterogeneous catalysis.

An improved protocol has been developed for the synthesis of symmetrical biaryl sulfides via a dominothiolation reaction using CuI as catalyst in the presence of DMAP as ligand. The coupling reaction of aryl halides was carried out in the presence of 5 mol % of CuI and 20 mol % of DMAP using thiourea as sulfur transfer agent. High yields of corresponding product were obtained by carrying out the reaction in DMSO at 120 °C.

We developed an efficient synthetic route for functionalized aryl-β- C -glycosides, which are difficult to prepare by conventional methods. An aryl halide having an ester, cyano, or carbonyl group was treated with 2,4,6-triisopropylphenyllithium in the presence of a δ-lactone (Barbier-type reaction conditions) to afford a coupling product. The following deoxygenation gave the desired aryl-β- C -glycoside in good yield.

An efficient approach to aryl azides, in short reaction times and good to excellent yields, has been developed via the reaction of aryl halides with sodium azide under Cu2O/tetraethylammonium prolinate catalysis.

The carbon–sulfur coupling reaction of aryl halides with thioacetamide using an MCM-41-immobilized bidentate nitrogen copper(I) complex [MCM-41-2N-CuI] as an efficient heterogeneous catalyst is described. Developed catalytic system is found to be effective for the coupling reaction of aryl halides with thioacetamide providing moderate to high yield of diaryl sulfides. This heterogeneous copper catalyst exhibits higher activity than CuI and can be recovered by a simple filtration of the reaction solution and reused for at least 10 consecutive trials without any decreases in activity.

An expedient and versatile, microwave-assisted procedure for the carbonylation of aryl halides with boronic acids, alcohols or amines in water or under neat conditions has been developed. The reaction is catalyzed by fluorous, oxime-based palladacycle 1 that shows an excellent recyclable property and low levels of Pd leaching. To demonstrate the usefulness of the protocol, we applied it to the preparation of compounds of pharmaceutical interest, including a precursor of the reverse transcriptase inhibitor, niacin, benzocaine and butamben.

A facile and efficient method for Ullmann-type C–N coupling reaction of amine and aryl halide catalyzed by CuI/metformin in EtOH is described. The advantages of this method are the use of an inexpensive and readily available catalyst and ligand, easy workup, shorter reaction time, improved yields, and the use of green solvent. Furthermore, this procedure is applied successfully for the modification of natural products, such as Vindoline and Tabersonin.

Ullmann-type C–N coupling reaction has been developed for the synthesis of 1-aryl indole derivatives by indoles and aryl halides in the presence of CuI/metformin (CuI/Met) in DMF. This method is very easy, rapid, and high yielding reaction for the synthesis of 1-aryl indoles. In particular, the metformin, which is used as ligand, is inexpensive and nontoxic that is considered to be relatively environmentally benign.