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Wittig reaction under Phase Transfer conditions was performed in a flow reaction system. Different bases, aldehydes, phosphonium salts, and flow reaction parameters were investigated, in absence of a phase transfert catalyst. An improvement of the reaction outcome (yield and reaction time) was achieved through the immersion of the reactor into an ultrasound bath.

A novel and efficient approach to alkenyl nitriles from allyl esters has been developed. A tandem Pd-catalyzed substitution and the subsequent oxidative rearrangement are involved in this transformation. The method provides an important supplement for the synthesis of alkenyl nitriles from allyl esters. Georg Thieme Verlag Stuttgart · New York.

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A highly stereoselective synthesis of (Z)-alk-2-enenitriles from aldehydes is accomplished by reaction with tris(trimethylsilyl)ketenimine, followed by alkali treatment.

Wittig reactions could be performed in perfluorosolvents using perfluorinated ylides, allowing both a very easy separation of the alkene from the phosphine oxide and a re-use of the latter by simple reduction of the crude oxide.

We describe copper-catalyzed cyanomethylation of imines and α,β-alkenes with a methylnitrile source and provide an efficient route to synthesize arylacrylonitriles and β,γ-unsaturated nitriles. This method tolerates aliphatic and aromatic alkenes substituted with a variety of functional groups such as F, Cl, Br, Me, OMe,tert-Bu, NO2, NH2and CO2H with good to excellent yields (69-98%). These systems consist of inexpensive, simple copper catalyst and acetonitrile with its derivatives (α-bromo/α-iodo-acetonitrile) and are highly applicable in the industrial production of acrylonitriles.

A series of ruthenium hydride N-alkyl heterocyclic carbene complexes has been investigated as catalysts for a tandem oxidation/Wittig/reduction reaction to give C-C bonds from alcohols. The C-H-activated carbene complex Ru(I iPr2Me2)′(PPh3) 2(CO)H (9) proves to be the most active precursor catalyzing the reaction of PhCH2OH and Ph3P=CHCN in 3 h at 70 °C. These results provide (a) a rare case in which N-alkyl carbenes afford higher catalytic activity than their N-aryl counterparts and (b) a novel example of the importance of NHC C-H activation in a catalytic cycle.

Boehmite nanoparticles are a cubic orthorhombic structure of aluminum oxide hydroxide containing hydroxyl groups attached to their surface, which were prepared in water using commercially available materials. A moisture- and air-stable palladium S-methylisothiourea complex supported on boehmite nanoparticles (Pd(0)-SMTU-boehmite) was prepared using a very simple and inexpensive procedure without an inert atmosphere using commercially available materials. This nanostructure compound was used as an excellent organometallic catalyst for Suzuki and Heck reactions in H2O or PEG-400. The synthesized nanoparticles were characterized using FT-IR, XRD, BET, TGA, TEM, SEM, EDS and ICP-OES techniques. Nitrogen adsorption/desorption measurements indicated that the boehmite nanoparticles have a BET surface area of about 122.8 m2 g-1. This heterogeneous nanocatalyst was easily separated from the reaction mixture and reused for several consecutive runs without significant loss of its catalytic efficiency or palladium leaching. The leaching of palladium from the catalyst was examined using hot filtration and ICP-OES techniques.

The design and synthesis of a new class of laser light activatable tetrazoles with extended π-systems is reported. Upon 405 nm laser light irradiation, these bithiophene-substituted tetrazoles underwent extremely fast 1,3-dipolar cycloaddition reactions with dimethyl fumarate with second-order rate constants approaching 4000 M-1 s-1. The resulting pyrazoline cycloadducts exhibited solvent-dependent red fluorescence, making these tetrazoles potentially useful as fluorogenic probes for detecting alkenes in vivo.

Arylcyclopropanes react with nitrosyl chloride activated by sulfur(VI) oxide to give the corresponding 5-aryl-4,5-dihydro-1,2-oxazoles in quantitative yields. The complex NOC1?2SO3 is a highly efficient nitrosating agent which makes it possible to involve in the process arylcyclopropanes having both donor and acceptor substituents in the aromatic ring. Nauka/Interperiodica 2007.

A visible-light-driven and room temperature photo-Wolff-Kischner reaction of sulfur ylides and N-tosylhydrazones has been developed for the first time to provide modular access to alkene synthesis. The high functional group tolerance and broad substrate scope were demonstrated by more than 60 examples. Both E- and Z-olefinic stereochemistry in the products could be controlled with excellent stereoselectivity. A series of mechanistic studies support that the reaction should proceed through a radical-carbanion crossover pathway, specifically involving addition of photo-generated sulfur ylide radical cations to N-tosylhydrazones to form carbanions and subsequent Wolff-Kischner process.

A chelation-assisted palladium-catalyzed CC bond cleavage of α, β-unsaturated ketone to form alkenyl nitrile in the presence of nitrile is disclosed on the basis of a formal group-exchange reaction formulated as C1C2 + C3 → C1C3 + C2, differing from normal alkene oxidative cleavage and metathesis type. The isolated key active Pd(II) complex as well as deuterium-labeled experiment revealed the necessity of the chelation group, and a plausible catalytic pathway was proposed.

The sodiation of substituted acrylonitriles and alkenyl sulfides in a continuous flow set-up using NaDA (sodium diisopropylamide) in EtNMe2 or NaTMP (sodium 2,2,6,6-tetramethylpiperidide)?TMEDA in n-hexane provides sodiated acrylonitriles and alkenyl sulfides, which are subsequently trapped in batch with various electrophiles such as aldehydes, ketones, disulfides and allylic bromides affording functionalized acrylonitriles and alkenyl sulfides. This flow-procedure was successfully extended to other acrylates by using Barbier-type conditions.

Reactions of 3-arylpropenenitriles [ArCH[dbnd]CHCN] with arenes [Ar'H] under the superelectrophilic activation conditions with Br?nsted superacid TfOH (CF3SO3H) or strong Lewis acid AlBr3 result, first, in the formation of products of hydroarylation of the carbon-carbon double bond, 3,3-diarylpropanenitriles [Ar(Ar’)CHCH2CN]. Reactions may go further in TfOH leading to 3-arylindanones, as products of intramolecular aromatic acylation by the electrophilically activated nitrile group. Intermediate cationic species, derived at the protonation of the starting 3-arylpropenenitriles onto the carbon of C[dbnd]C bond and the nitrile nitrogen, have been studied by DFT calculation. A plausible reaction mechanism including the formation of highly reactive dications [(Ar)HC+–CH2C+ = NH] has been proposed. The obtained 3,3-diarylpropanenitriles have been transformed into pharmaceutically valuable 5-(2,2-diarylethyl)-1H-tetrazoles [Ar(Ar’)CHCH2Tetr] and 3-diarylpropylamines [Ar(Ar’)CH(CH2)2NH2] by the reactions with NaN3 and LiAlH4 correspondingly.

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.

A series of β2-adrenoceptor agonists with an 8-(2-amino-1-hydroxyethyl)-6-hydroxy-1,4-benzoxazine-3(4H)-one moiety is presented. The stimulatory effects of the compounds on human β2-adrenoceptor and β1-adrenoceptor were characterized by a cell-based assay. Their smooth muscle relaxant activities were tested on isolated guinea pig trachea. Most of the compounds were found to be potent and selective agonists of the β2-adrenoceptor. One of the compounds, (R)-18c, possessed a strong β2-adrenoceptor agonistic effect with an EC50 value of 24 pM. It produced a full and potent airway smooth muscle relaxant effect same as olodaterol. Its onset of action was 3.5 min and its duration of action was more than 12 h in an in vitro guinea pig trachea model of bronchodilation. These results suggest that (R)-18c is a potential candidate for long-acting β2-AR agonists.

Direct C-H functionalization of aryl ethers remains challenging owing to their low reactivity and selectivity. Herein, a novel strategy for nondirected C-H alkenylation of aryl ethers promoted by a dual ligand catalyst was demonstrated. This catalytic system readily achieved the highly efficient alkenylation of alkyl aryl ethers (anisole, phenetole, n-propyl phenyl ether, n-butyl phenyl ether and benzyl phenyl ether), cyclic aryl ethers (1,4-benzodioxan, 2,3-dihydrobenzofuran, dibenzofuran), and diphenyl oxides. Moreover, the proposed methodology was successfully employed for the late-stage modification of complex drugs containing the aryl ether motif. Interestingly, the compounds developed herein displayed fluorescent properties, which would facilitate their biological applications.

Nickel-catalyzed transformation of alkene-tethered oxime ethers to nitriles using a traceless directing group strategy has been developed. A series of alkene-tethered oxime ethers derived from benzaldehyde and cinnamyl aldehyde derivatives were converted into the corresponding benzonitriles and cinnamonitriles in 46-98% yields using the nickel catalyst system. Control experiments showed that the alkene group tethered to an oxygen atom on the oximes via one methylene unit plays a key role as a traceless directing group during the catalysis.

We designed and synthesized a novel catalyst consisting of ordered mesoporous silica (SBA-15) functionalized with bis(thiourea) (BTU) linker. The regular and unique pore channels of BTU-SBA-15 ensure proper control of the size and homogeneous distribution of palladium nanoparticles. The physiochemical properties of the hybrid Pd?BTU-SBA-15 pre-catalyst were investigated using various techniques. The proposed catalyst is found to be very active, reusable, stable and scalable, and has excellent reactivity and selectivity for Suzuki and Heck coupling reactions under very mild and sustainable reaction conditions.

In this study, the surface of magnetic MCM-41 nanoparticles (MCM-41/Fe3O4) was modified by 3-Aminopropyltriethoxysilane (APTES) and further, 1-methyl imidazole was anchored on their surface using cyanuric chloride as a linker. Then, Pd2+ ions were immobilized on the surface of the modified MCM-41/Fe3O4 (Pd-imi-CC@MCM-41/Fe3O4), and its application was studied as a magnetically recyclable nanocatalyst in carbon-carbon coupling reactions between a wide range of aryl halides and butyl acrylate, methyl acrylate, acrylonitrile, phenylboronic acid, or 3,4-difluorophenylboronic acid under the conditions of a phosphine-free ligand and an air atmosphere. This catalyst has the advantages of both the Fe3O4 nanoparticles and mesoporous MCM-41. The structure of the catalyst was characterized via TEM, SEM, EDS, WDX, N2 adsorption-desorption isotherm, XRD, TGA, FT-IR, and AAS. Also, the recovered catalyst was characterized via SEM, AAS and FT-IR. All the products from the carbon-carbon coupling reaction were obtained with excellent yields and high TON and TOF values, which indicate the high efficiency and activity of this catalyst. The selectivity of this catalyst was studied with various aryl halides bearing different functional groups. Furthermore, the heterogeneity and stability of Pd-imi-CC@MCM-41/Fe3O4 was studied via AAS, and leaching and poisoning tests. According to the results, this heterogeneous catalyst can be reused several times.

Unprecedented Co@g-C3N4 catalyzed visible light driven efficient conversion of a variety of aldehydes into corresponding nitriles is reported. Operational simplicity, excellent yield of pure products (87–94%), ambient reaction condition, using aqueous methanol as solvent, visible-light photocatalysis are the salient features of envisaged methodology for direct conversion of aldehydes into nitriles. Furthermore, reusability of Co@g-C3N4 was checked up to five runs and it was noticed that there was no substantial change in morphology as well as the catalytic efficiency of catalyst.

Nitriles are found in many bioactive compounds, and are among the most versatile functional groups in organic chemistry. Despite many notable recent advances, however, there are no approaches that may be used for the preparation of di- or tri-substituted alkenyl nitriles. Related approaches that are broad in scope and can deliver the desired products in high stereoisomeric purity are especially scarce. Here, we describe the development of several efficient catalytic cross-metathesis strategies, which provide direct access to a considerable range of Z- or E-di-substituted cyano-substituted alkenes or their corresponding tri-substituted variants. Depending on the reaction type, a molybdenum-based monoaryloxide pyrrolide or chloride (MAC) complex may be the optimal choice. The utility of the approach, enhanced by an easy to apply protocol for utilization of substrates bearing an alcohol or a carboxylic acid moiety, is highlighted in the context of applications to the synthesis of biologically active compounds.

A simple, mild, and practical process for direct conversion of aldehydes to nitriles was developed feathering a wide substrate scope and great functional group tolerability (52 examples, over 90% yield in most cases) using inorganic reagents (NH2OH/Na2CO3/SO2F2) in DMSO. This method allows for transformations of readily available, inexpensive, and abundant aldehydes to highly valuable nitriles in a pot, atom, and step-economical manner without transition metals. This protocol will serve as a robust tool for the installation of cyano-moieties to complicated molecules.

A palladium–fibroin complex (Pd/Fib.) was prepared by the addition of sonicated fibroin fiber in water to palladium acetate solution. Pd (OAc)2 was absorbed by fibroin and reduced with NaBH4 at room temperature to the Pd(0) nanoparticles. Powder-X-ray diffraction, scanning electron microscopy–energy-dispersive X-ray spectroscopy, Fourier transform-infrared, CHN elemental analysis and inductively coupled plasma-atomic emission spectroscopy were carried out to characterize the Pd/Fib. catalyst. Catalytic activity of this finely dispersed palladium was examined in the Heck coupling reaction. The catalytic coupling of aryl halides (-Cl, -Br, -I) and olefins led to the formation of the corresponding coupled products in moderate to high yields under air atmosphere. A variety of substrates, including electron-rich and electron-poor aryl halides, were converted smoothly to the targeted products in simple procedure. Heterogeneous supported Pd catalyst can be recycled and reused several times.

Polymer-supported palladium was synthesized by applying a single-step wet chemical synthesis route and the resultant composite material was characterized by means of various techniques. Infrared and UV–visible spectra provided information on the chemical structure of the polymer. Microscopy techniques showed the general morphology of the polymer. The oxidation state of palladium was determined using the X-ray photoelectron spectroscopy method. The synthesized material was applied as a heterogeneous catalyst for the Heck coupling reaction and also as an electrocatalyst for the oxidation of cysteine.

This study describes an efficient class of bis-N-heterocyclic carbene (bis-NHC) salts that can be easily made from commercially available and inexpensive starting materials. The application of these salts to Pd-catalyzed reactions is described. The palladium (Pd) catalyst generated in situ was highly effective under mild reaction conditions.

A palladium(II) catalyst, in the presence of Selectfluor, enables the efficient and chemoselective transformation of primary amides into nitriles. The amides can be attached to aromatic rings, heteroaromatic rings, or aliphatic side chains, and the reactions tolerate steric bulk and electronic modification. Dehydration of a peptaibol containing three glutamine groups afforded structure-activity relationships for each glutamine residue. Thus, this dehydration can act similarly to an alanine scan for glutamines via synthetic mutation.

The present invention refers to a process for a Rh-catalyzed Anti-Markovnikov hydrocyanation of terminal alkynes which process discloses, for the first time, the highly stereo- and regio-selective hydrocyanation of terminal alkynes to furnish E- configured alkenyl nitriles and the catalyst used in the present process.

The direct conversion of α,β-unsaturated aldehydes to corresponding nitriles promoted by Pd(OAc)2 and phthalic acid which was hydrolyzed from N-hydroxyphthalimide (NHPI) has been disclosed. Additionally, it was found that when water was used as the solvent, α,β-unsaturated amides was obtained as the main products in good to excellent yields. It was first reported that NHPI was utilized as the nitrogen source to synthesize α,β-unsaturated nitriles and amides from aldehydes. Control experiment demonstrated that aldehydes undergo a process of oximation and dehydration to form nitriles and amides.

Palladium ions were successfully immobilized within the pores of open metal site (OMS) metal organic frameworks (MOFs) with Schiff-base (2-Py-SI) grafted in OMS-Cu (BDC) using the hydrothermal method. This Schiff-base complex on the Cu (BDC) greatly increased catalytic activity and acted as an efficient stabilizer of Pd ions. The hydrothermal method was a more efficient method for generating small metal ions in the MOF structures. The results revealed that the PdII@Cu (BDC)/2-Py-SI is a promising catalyst for the Mizoroki-Heck coupling reaction. The proposed catalyst has better recyclability and can be reused several times without apparent loss of activity.

The invention provides a method for synthesizing substituted acrylonitrile with a one-pot process. Beta-aryl substituted acrylonitrile is prepared from 0.01-1.0 mol of aryl substituted methanol or heterocycle substituted methanol as a raw material and a solvent adopting acetonitrile with the concentration of 0.2-2.0 mol/L under the alkaline action. In the oxygen atmosphere, a semiconductor photocatalyst is added, the mixture reacts under assistance of light illumination, and the reaction speed and the yield can be greatly increased. Raw materials for a reaction are easy to obtain, the method is simple and convenient, and the product has important application value.

Abstract: The direct supporting of Pd-arginine complex on boehmite nanoparticles (Pd(0)-Arg-boehmite) was reported as a moisture- and air-stable, heterogeneous, excellent and novel organometallic catalyst, which applied for the Suzuki and Heck cross coupling reactions through coupling of phenylboronic acid, 3,4-difluoro phenylboronic acid, sodium tetraphenyl borate, butyl acrylate, methyl acrylate, acrylonitrile and styrene with a wide range of aryl halide including Cl, Br and I. Pd(0)-Arg-boehmite was prepared for the first time via simple, environmental and inexpensive procedure in water and ethanol without inert atmosphere or high temperature using commercially available materials, and characterized by XRD, TGA, TEM, SEM, EDS and ICP-OES techniques. The leaching of palladium and heterogeneity test of this catalyst was studied by hot filtration and ICP-OES techniques; resulting we found that this catalyst was demonstrated remarkable and excellent recyclability. Graphical Abstract: Boehmite nanoparticles were prepared by inexpensive procedure in water at room temperature and directly immobilized with a new type of Pd-arginine complex. After characterization of this catalyst, its application has been studied for the C–C coupling reactions. [Figure not available: see fulltext.]

A friendly protocol is reported to achieve cyanation of aromatic and vinylic boronic acids using nontoxic and readily available α-cyanoacetates as a cyano source under aerobic conditions. Many aryl/vinyl boronic acids (as well as some iodides and bromides) are amenable substrates to give aryl nitriles and acrylonitriles. This cyanation method provides a safe and operationally convenient alternative to traditional ones requiring toxic cyanide salts.

Abstract: A green, convenient, ecological and recyclable method comprising dual functionalized, task-specific, ionic liquid (IL)-triggered, in situ-generated Pd nanoparticles (NPs) and their catalytic application for Heck–Matsuda coupling of olefins is described. Both arenediazonium tetrafluoroborate and silica sulphate salts are coupled with olefins under ligand-free and aerobic conditions at ambient temperature furnishing excellent yields of products. The Ionic liquid used acts as a reducing as well as stabilizing agent for in situ-generated Pd NPs. The formed NPs were characterized by transmission electron microscopy (TEM) analysis, having a size below 50?nm, and exhibited high catalytic activity. The catalytic system can be reused for eight times effectively without any significant loss of activity. The method was found to be highly stereo-specific, giving exclusively the ‘E’ isomer.

(Trimethylsilyl)acetonitrile reacts smoothly with dimethyl acetals in the presence of stoichiometric trimethylsilyl trifluoromethanesulfonate (TMSOTf) to yield β-methoxynitriles. The ideal substrates for this reaction are acetals derived from aromatic aldehydes. Elimination to the corresponding α,β-unsaturated nitriles is observed as the major product in the case of electron-rich acetals. A mechanistic hypothesis that includes isomerization of the silylnitrile to a nucleophilic N-silyl ketene imine is presented.

An efficient nickel-catalyzed decarbonylative cyanation reaction which allows the direct functional-group interconversion of readily available esters into the corresponding nitriles was developed. This reaction successfully offers access to structurally diverse nitriles with high efficiency and excellent functional-group tolerance and provides a good alternative to classical synthetic pathways from diazonium salts or organic halide compounds.

Transition-metal-catalyzed cyanation of aryl halides is a process of significant importance in the preparation pharmaceuticals, organic materials and agrochemicals. Here, we demonstrate a palladium-catalyzed decarbonylative cyanation of amides by highly selective carbon-nitrogen bond cleavage for the synthesis of a wide range of aryl nitriles. The utility of this technology is demonstrated by the synthesis of isotopically labeled aryl nitriles and orthogonal cross-coupling reactions of bench-stable amides to establish cross-coupling synthons with opposite polarity.

We report the first highly stereo- and regioselective hydrocyanation of terminal alkynes to furnish E-configured alkenyl nitriles. Acrylonitriles can be accessed on gram scale with broad substrate scope and functional group tolerance. The hydrocyanation reaction employs acetone cyanohydrin as a practical alternative to HCN gas.

The invention relates to a preparation method of a trans-alpha, beta-unsaturated nitriles compound. The method comprises the following steps: uniformly mixing a benzyl alcohol compound, acetonitrile, a promoter and alkali, and carrying out reflux reaction completely to obtain reaction liquid; carrying out conventional extraction, drying, concentration and column chromatographic separation on the reaction liquid in sequence to obtain the trans-alpha, beta-unsaturated nitriles compound. The preparation method belongs to double-component one-boiler reaction, so that conditions are relatively mild, and raw materials are easy to prepare and readily available; the operation is simple, the yield is relatively high, and greenness, environment friendliness and economy can be realized; large-scale production can be realized; the preparation method has an extremely good application potential on the aspect of fine chemicals, and has a relatively good industrial application prospect.

An arsine-mediated Wittig reaction for the synthesis of olefins is described. After heating triphenylarsine in the presence of an activated alkyl bromide for 30?min, the resulting arsonium salt condensed with aldehydes in as little as 5?min at room temperature, yielding the olefins in high yields. Aromatic, heteroaromatic, and alkyl aldehydes were all suitable substrates for this process.

Iteratively executed with exquisite spatial and temporal control, the selective isomerization of polarized alkenes underpins a plethora of complex biological processes ranging from natural product biosynthesis through to the mammalian visual cycle. However, nature's proficiency conceals the inherent difficulties in replicating this contrathermodynamic transformation in the laboratory. Recently, we disclosed the first highly Z-selective isomerization of polarized alkenes, employing the cinnamoyl chromophore as a retinal surrogate under UV-irradiation (402 nm) with (-)-riboflavin (Vitamin B2) as an inexpensive, organic photocatalyst (J. Am. Chem. Soc. 2015, 137, 11254-11257). This study was inspired by the propensity of crystalline (-)-riboflavin in the eyes of vertebrates to invert the intrinsic directionality of retinal isomerization. Herein, we extend this methodology to include a bioinspired, catalytic E → Z isomerization of α,β-unsaturated nitriles, thereby mimicking the intermediate Opsin-derived, protonated Schiff base in the visual cycle with simple polarized alkenes. Replacement of the iminium motif by a cyano group is well tolerated and gives an additional degree of versatility for postisomerization functionalization. Broad substrate scope is demonstrated (up to 99:1 Z:E) together with evidence of mechanistic dichotomy via both singlet and triplet energy transfer mechanisms. Kinetic studies, temperature dependent photostationary state correlations and investigation of substituent-based electronic perturbation of the alkene identified polarization combined with increased Z-isomer activation barriers as the selectivity governing factors in catalysis. This investigation demonstrates the importance of internal structural preorganization on photostationary composition and explicates the augmented Z-selectivity upon hydrogen-alkyl exchange at the β-position of the alkene.

A relay formalism is proposed herein for categorizing the interplay among reactants, target product, and catalytic center in transition-metal catalysis, an important factor that can dictate overall catalysis viability and efficiency. In this formalism, transition-metal catalysis can proceed by dissociative relay, associative covalent relay, and associative dative relay modes. An intriguing associative covalent relay process operates in rhodium(III)-catalyzed oxadiazolone-directed alkenyl C?H coupling with alkynes and allows efficient access to primary pyridinylamines. Although the primary pyridinylamine synthesis mechanism is posteriori rationalized, the relay formalism formulated herein can provide an important mechanistic conceptual framework for future catalyst design and reaction development.

We report herein a Rh(III)-catalyzed alkenyl C-H activation protocol for the coupling of oxadiazoles with alkynes and synthesis of 2- acylamino and 2-amino pyridines, an important heterocyclic scaffold for various naturals products and synthetic pharmaceuticals bearing a readily reacting functional group. The selective protection/deprotection of amino groups through simple solvent switching, good functional group compatibility, superior product yield, and high regioselectivity are some of the notable synthetic features witnessed in this reaction protocol.

The silica based hollow nanosphere (silica-HNS) containing polymer of polyaniline was synthesized and chosen as a promising support for PdNPs. Then it was applied as a green catalyst in the reaction of Heck coupling with high yield. TEM and SEM-EDX/mapping images were used to study the structure and morphology. FT-IR spectroscopy, Thermal gravimetry analysis (TGA), and BET were used to characterize and investigate the catalyst. Also, the amounts of Pd loading were characterized by ICP-AES technique. Catalyst recyclability showed 5 successful runs for the reaction.

A highly efficient and easily recyclable magnetic nanoparticle supported palladium catalyst was developed and applied in the Heck and Sonogashira reactions in order to show its catalytic applicability in Pd-catalyzed C-C coupling protocols. The catalyst was prepared using a simple chemical process. First, the prepared Fe3O4@SiO2 nanoparticles were reacted with (3-chloropropyl)-trimethoxysilane (3-CPTMS) in order to synthesis chloro-functionalized magnetic nanoparticles (CPS-MNPs). The substitution reaction of synthetic NNN ligand with CPS-MNPs yields the production of CPS-MNPs-NNN ligand. Finally, immobilization of palladium species on CPS-MNPs-NNN ligand surface afforded CPS-MNPs-NNN-Pd catalyst. The structure and morphology of the prepared nanocatalyst was characterized using various methods such as SEM, TEM, XPS, EDX, CHN, ICP, XRD, FT-IR and VSM techniques. The TEM images show that the sizes of the palladium catalyst are in the range of 8-15 nm. The Heck and Sonogashira coupling reactions were performed in the presence of a catalytic amount of this catalyst system (0.5 mol%) and good yields of products were obtained. Due to the magnetic nature of the catalyst it can be separated from the reaction mixture easily by applying an external magnetic field. Heterogeneity tests affirmed that the catalytic activity stayed indefectible during multiple reaction cycles.

A heterogeneous fluoride catalyst was found to enable the straightforward formation of alkenyl nitriles from the reaction of aldehydes and simple or substituted acetonitriles, in the presence of commercially available silazanes and in solvent-free conditions. The protocol afforded the products in good to excellent yields with selectivity values dependent on the nature of the substrates. It represents an alternative to classic approaches using stoichiometric strong bases, and the catalyst can be easily recovered and reused for consecutive cycles.

We have disclosed for the first time the copper-promoted C≡N triple bond cleavage of coordinated cyanide anion under a dioxygen atmosphere, which enables a nitrogen transfer to various aldehydes. Mechanistic study of this unprecedented transformation suggests that the single electron-transfer process could be involved in the overall course. This protocol provides a new cleavage pattern for the cyanide ion and would eventually lead to a more useful synthetic pathway to nitriles from aldehydes.

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The Schmidt reaction of aromatic aldehydes using a substoichiometric amount (40 mol %) of triflic acid is described. Low catalyst loading was enabled by a strong hydrogen-bond-donating solvent hexafluoro-2-propanol (HFIP). This improved protocol tolerates a broad scope of aldehydes with diverse functional groups and the corresponding nitriles were obtained in good to high yields without the need for aqueous work up.

Herein is reported the selective transformation of aldehydes to nitriles in the presence of hydroxylamine-O-sulfonic acid (NH2OSO3H) as a source of the N atom and acidic water. The reaction works with high yields for a large array of aromatic and aliphatic aldehydes, as well as hindered aldehydes and conjugated aldehydes without purification. The reaction conditions are very mild and tolerate a wide array of functional groups. In principle, the reaction can be completed in vinegar.

The use of a supported Pd complex on magnetic nanoparticles as an efficient and green catalyst for the Suzuki, Stille and Heck cross-coupling reactions is presented. The present research is focused on investigating the recycling, reusability and stability of the catalyst in the reaction. The recycled Fe3O4@PTA-Pd catalyst was used at least five times with comparable activities to that of the fresh catalyst. The catalytic coupling of 4-bromotoluene as a model reaction suggested that there was no leached palladium in the reaction mixture. The structure of the catalyst was characterized by TGA, EDS, ICP-OES, XRD, VSM, FT-IR and SEM analysis.

An efficient, green and practical approach to synthesize alkenyl nitriles using new supported Cu(II) catalyst via aromatic aldehydes and acetonitrile was developed. The novel catalyst was characterized by FT-IR, XRD, SEM/EDX, TEM, TGA and VSM. Interestingly, the catalyst was found to be active for synthesis of alkenyl nitriles, which were readily obtained in good yields under mild conditions. But most importantly, the original catalyst could be conveniently recovered and recycled from the reaction system by applying an external magnet and reused in four cycles without significant loss in catalytic activity. Graphical Abstract: [Figure not available: see fulltext.]

Using NH4I as the supporting electrolyte as well as the precursor of an I2 promoter and nitrogen source, a highly efficient electrochemical route was developed to convert aldehydes to nitriles with excellent yields under mild reaction conditions. This electrochemical process could effectively avoid the direct use of NH3 gas, molecular iodine, and oxidants.

N,N,N′,N′-Tetramethylethylenediamine dioxide (TMEDAO2) was explored as a more atom economical co-oxidant for the Ley-Griffith oxidation of alcohols to aldehydes. TMEDAO2 was found to selectivity oxidise benzylic and allylic alcohols in comparable yields to that of the standard Ley-Griffith co-oxidant (NMO). Importantly TMEDAO2 facilitated tandem Ley-Griffith-Wittig reactions with stabilised ylides, in good to excellent yields, without the requirement of anhydrous conditions.

A highly efficient enantioselective hydrogenation of α,β-unsaturated nitriles catalyzed by Rh-(R,R)-f-spiroPhos complex has been developed. With Rh-(R,R)-f-spiroPhos catalyst and under mild conditions, a wide range of α,β-unsaturated nitriles including the (E)- and (Z)-isomers of 3-alkyl-3-aryl, 3,3-diaryl, and 3,3-dialkyl α,β-unsaturated nitriles were hydrogenated to the corresponding chiral nitriles with excellent enantioselectivities (up to 99.9% ee) and high turnover numbers (TON up to 10,000).

Iron hydride complexes of the general formula P2Fe(NO)CO)H are highly active catalysts for the hydrosilylation of aldehydes or ketones and phosphine oxides. Depending on the solvent, the in situ reduction of the phosphine oxide can be faster than the corresponding hydrosilylation of a carbonyl group. This unusual activity was used within the context of catalytic Wittig olefination. Picture perfect: Iron hydride complexes of the general formula P2Fe(NO)CO)H are highly active catalysts for the hydrosilylation of aldehydes or ketones and phosphine oxides. Depending on the solvent, the in situ reduction of the phosphine oxide can be faster than the corresponding hydrosilylation of a carbonyl group. This unusual activity is used within the context of catalytic Wittig olefination. EWG=Electron-withdrawing group.

An efficient catalytic route for the synthesis of α,β-unsaturated nitriles from easily accessible gem-dibromoolefins has been developed. The method utilized inexpensive reagents such as Cu2O as a catalyst, l-proline as a ligand and NaCN as a cyanide source to afford α,β-unsaturated nitriles in high yields (62-86%). A deuterium exchange study has shown that one of the bromide atoms of gem-dibromoolefins exchanges with cyanide while the other with a deuterium atom.

We have developed a highly selective method for the synthesis of α,β-unsaturated amides and alkenyl nitriles from readily available propargylic alcohols. The reaction proceeded smoothly under the neutral conditions with hydroxylamine hydrochloride (NH2OH·HCl) as the nitrogen source. The development of these new strategies has significantly extended the application of hydroxylamine hydrochloride to the chemistry of propargylic alcohols. Moreover, both secondary and tertiary alcohols have been highly regioselectively transformed to the desired products with good functional group compatibility.