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A synthesis of 4 - (arylmethyl)proline by using Suzuki cross-couplings was developed. The route permits access to a variety of 4-substituted proline derivatives bearing various aryl moieties that expand the toolbox of proline analogues for studies in chemistry and -biology. [ABSTRACT FROM AUTHOR]

We design and develop novel polyfluorene-based anion exchange polyelectrolyte (AEP) with introducing alkyl spacer, PFPB-QA. PFPB-QA could provide improved membrane-forming property due to its free rotatable alkyl spacers and this AEP possesses high ionic conductivity, mechanical property and alkaline stability, which utilized as anion exchange membrane water electrolysis (AEMWE). Furthermore, PFPB-QA based AEMWEs showed a cell performance of 1.53 A cm−2 (1M KOH solution at 70 °C) at 2.0 V and high durability compared with FAA-3–50 based AEMWE. [Display omitted] • We design and develop novel polyfluorene-based anion exchange polyelectrolyte (AEP) with introducing alkyl spacer, PFPB-QA. • PFPB-QA possesses high ionic conductivity, mechanical and alkaline stability, which utilized as anion exchange membrane water electrolysis. • The PFPB-QA based AEMWEs achieve a cell performance of 1.53 A cm−2 at 2.0 V and high durability compared with FAA-3–50 in 1 M KOH solution at 70 °C. • Novel design strategy could provide a guideline for AEPs to achieve both high efficiency and long-term durability, simultaneously. Aryl ether-free polymers have attracted considerable attention in recent years for their application in anion exchange membrane (AEM) fuel cells (AEMFCs) and water electrolysis (AEMWE). Here, an aryl ether-free polyfluorene-based polymer bearing pendent ammonium groups in side chains and propyl spacers in its polymer backbone is synthesized through the Suzuki cross-coupling reaction. The propyl spacer introduced into the backbone improves the flexibility of the polymer and allows effective ionic cluster formation by the polymer. Compared to polyphenylene oxide (PPO), which has a similar molecular weight, quaternized poly[9,9-bis(6-bromohexyl)fluorene]–co-[4,4-bis((4-phenyl)propyl)biphenyl)] (PFPB-QA) polymers show significantly superior membrane-forming properties owing to the propyl spacers. The PFPB-QA membrane also exhibits high ionic conductivity (122 mS cm−1 at 80 °C) and excellent alkaline stability (1 M KOH at 80 °C for 720 h). Moreover, the AEMWE utilizing PFPB-QA exhibits a current density of 1.53 A cm−2 at 2.0 V in 1 M KOH at 70 °C. Therefore, the present study shows that an aryl ether-free polymer with an alkyl spacer has excellent mechanical properties, ionic conductivity, alkaline stability, and cell performance. [ABSTRACT FROM AUTHOR]

Conditioning the nature of metal active sites for better performance by well designing and constructing the support material is always appealing in heterogeneous catalysis. Herein, Cu species was introduced into the bulk phase of carbon nitride to strengthen the interlayer connection and optimize the electronic structure. The resulting material (CN-Cu) demonstrated an enhanced support effect for Pd catalyzed Suzuki cross-coupling reactions under light illumination. Detailed characterizations showed that Cu species were atomically incorporated in intra/interlayer of CN framework through coordinating with pyridinic nitrogen, leading to improved light absorption and more efficient charge carrier transfer. More importantly, the electronic effect of CN-Cu to the surface Pd was enhanced by the electron drift from Cu to N, thereby rendered an electron-rich Pd surface. Such Pd surfaces allowed faster electron injection from Pd(0) to the LUMO of aryl halides and therefore accelerate the rate-determining step of the coupling reaction. [Display omitted] • Single-atom Cu was incorporated into graphitic carbon nitride (CN-Cu) through a facile preorganization strategy. • The support effect originated from the Cu in bulk phase of CN on the photocatalytic activity of Pd for Suzuki cross coupling reaction was carefully investigated. • The electronic effect of CN-Cu toward the surface Pd was enhanced by the electron drift from Cu to the pyridinic N of carbon nitride. • The rate-determining step of the coupling reaction was accelerated by the electron contribution from Cu to Pd surface. [ABSTRACT FROM AUTHOR]

Upon treatment with thiophenol or neomenthyl mercaptane, chloroacetand propionamides with an additional Nor S-donor substituent in the amine part gave new multidentate ligands readily undergoing direct cyclopalladation in the reaction with PdCl(NCPh). The realization of κ-X, N, S-coordination (X = N, S) in the complexes obtained was confirmed by IR and NMR spectroscopy and, in some cases, by single-crystal X-ray crystallography. The evaluation of catalytic activity of the palladocycles in the Suzuki cross-coupling of aryl bromides with PhB(OH) allowed us to establish the principal structure-activity correlations. [ABSTRACT FROM AUTHOR]

A direct and catalyst-free method for the intramolecular aminoboration of unfunctionalized olefins is reported. In the presence of BCl3 (1 equiv) as the sole boron source, intramolecular aminoboration of sulfonamide derivatives of 4-penten-1-amines, 5-hexen-1-amines, and 2-allylanilines proceeded readily without the use of any catalyst. The boronic acids obtained after hydrolysis could be converted into the corresponding pinacol borates in a straightforward manner by treatment with pinacol under anhydrous conditions. [ABSTRACT FROM AUTHOR]

This paper discusses the synthesis of the amide ligand N,N-diisopropyl quinoline-2-carboxamide from quinoline-2-carboxylic acid and diisopropylamine. The prepared ligand was utilized in the palladium catalyzed Suzuki cross-coupling reaction in ethanol-water 1:1 (v/v). The reaction exhibited high catalytic efficiency with low Pd loading (0.05 mol %) under mild reaction conditions (at 60–90 °C under air atmosphere). In this study, the catalyst was successfully used in coupling reactions between various aryl halides with phenylboronic acid to obtain desired products in excellent yields. Spectrometric methods of 1 H NMR, 13 C NMR, and HR-MS were used to characterize this amide ligand, and its binding properties toward the Pd center were also investigated in detail via HR-MS measurements. [ABSTRACT FROM AUTHOR]

This paper describes synthesis of Pd-containing catalysts of Suzuki cross-coupling based on amino-functionalized hypercrosslinked polystyrene. The investigation of the influence of a palladium concentration, solvent composition, temperature, type and concentration of base, and a type of a gas phase was carried out. It was shown that the catalyst developed allows achieving conversion of 4-bromoanisole higher than 98% for less than 1 h at mild reaction conditions and in the absence of a phase transfer agent. Catalyst reduction was found to result in formation of small Pd nanoparticles (about 3 nm in diameter) and a large number of Pd clusters, which are highly active in Suzuki-Miyaura cross-coupling (conversion of 4-bromoanisole reached 90.2% for 3 h). [ABSTRACT FROM AUTHOR]

An efficient alkylation method of functionalized alkyl halides under mild nickel-catalyzed C( sp3)C( sp2) Suzuki cross-coupling conditions is described. The features of this approach are excellent functional group compatibility, low cost nickel catalyst, and the use of a mild base. This is also the first successful example of the nickel-catalyzed direct 2,2-difluoroethylation or 2,2,2-trifluoroethylation of aryl-/heteroarylboronic acids. [ABSTRACT FROM AUTHOR]

A series of new fluoroarene derivatives of artemisinin were prepared using Suzuki and Sonogashira cross-coupling reactions. An antifungal and antitumor activity was evaluated against opportunistic pathogen Fusarium oxysporum and Hela cancer cell line. All these derivatives have shown moderate to good activity. [ABSTRACT FROM AUTHOR]

A series of novel star-shaped small molecules with triphenylamine as the core, oligothiophene as the spacer and 1,8-naphthalimide as the electron withdrawing end-group were synthesized and used as donor materials for solution-processed organic solar cells. Direct arylation and Suzuki cross-coupling were used to synthesize the key intermediates and star-shaped molecules. The star-shaped molecules showed good thermal stability, intense absorption in the range of 300–700 nm, and deep HOMO energy level. A bulk heterojunction organic solar cell with one of the star shaped molecules in combination with PC 71 BM as the active layer gave a power conversion efficiency of 2.32% with a high open-circuit voltage up to 0.94 V. The influence of the spacer between the triphenylamine core and the peripheral 1,8-naphthalimide function group on the optical and photovoltaic properties was also investigated. Our studies indicated that 1,8-naphthalimide can be used as a promising building block for the synthesis of novel donor materials for organic solar cells. [ABSTRACT FROM AUTHOR]

By using H 2 O 2 as clean oxidant instead of air in previous fabrication process, a new nano palladium catalyst supported on polyaniline (nano Pd@PANI) with low Pd loading can be smoothly achieved by oxidative polymerization of the aniline with a reduced amount of PdCl 2 (currently 0.12% Pd only vs. previously 2.5% Pd). Although this new catalyst contains much less amount of Pd in comparison with the old nano Pd@PANI catalyst (currently only 0.75% Pd vs. previously 10.0% Pd), it is still found to be an effective catalyst for the Suzuki coupling of aryl halides and aryl boric acids, affording biphenyl products in excellent yields with dramatically enhanced turnover numbers (TON, 4.7 × 10 3 vs. 880). [ABSTRACT FROM AUTHOR]

An efficient method for the synthesis of 6-thienyl-substituted 2-amino-3-cyanopyridines by the ring transformation in the corresponding pyrimidines was developed. Further modification of the pyridines obtained under conditions of a room temperature aerobic Suzuki reaction in the presence of trans-bis(dicyclohexylamine)palladium(II) acetate as a catalyst was studied [ABSTRACT FROM AUTHOR]

New symmetrically substituted derivatives of 2,5-bis(4-arylphenyl)-1,3,4-oxadiazole were prepared from 2,5-bis(4-bromophenyl)-1,3,4-oxadiazole and various thiophene-, furan-, pyridine- or benzene-containing boronic acids by a palladium catalyzed Suzuki cross-coupling reaction under the conditions of the phase transfer catalysis. The structure of the products, the absorption and emission spectra and their electrochemistry were also studied. [ABSTRACT FROM AUTHOR]

Lycogarubin C, permethyl storniamide A, and lamellarin G trimethyl ether are pyrrole containing, natural products, which exhibit interesting biological properties. Such properties include anti-tumor activity on a variety of cancer cell lines including those that confer drug resistance, inhibition of HIV integrase, and vascular disrupting activity. We now describe the use of methyl and ethyl 3-bromo-2-formylpyrrole-5-carboxylate as building blocks for the formal synthesis of these three highly functionalized, bioactive pyrroles. These new building blocks will now provide ready access to the natural products and many novel analogs due to the ability to easily modify positions 2,3,4, and 5 of the pyrrole core. [ABSTRACT FROM AUTHOR]

An efficient Pd-catalyzed Suzuki cross-coupling reaction of sterically crowded 4-chlorocoumarin derivatives with air- and moisture-stable potassium organotrifluoroborates is developed. This methodology has been used to generate a series of novel alkyl, aryl, and vinyl substituted coumarin derivatives in good to excellent yields. The twisted conformation of the vinyl groups in the X-ray crystal structures of (2-oxo-4-vinyl-2 H -chromen-3-yl)methyl acetate ( 2 ) and (2-oxo-4-vinyl-2 H -chromen-3-yl)methyl 2,2,2-trichloroacetimidate ( 3 ), along with the atropisomerism of 3-(hydroxymethyl)-4-(2-methoxyphenyl)-2 H -chromen-2-one ( 1d ), are evidence of the steric crowding in these adducts. [ABSTRACT FROM AUTHOR]

Rod-like oligomers consisting of thiophene and phenylene rings have proven to be highly interesting building blocks for the preparation of self-assembled, well-defined nanoaggregates via vapor deposition on solid supports. Changing the molecules' chain length and substitution pattern allows to tailor the aggregates' optical properties and morphologies. Thus, there is an ongoing demand for the synthesis of functionalized oligo(het)arylenes. Here, we describe an efficient and general approach for a broad spectrum of such molecules using a Suzuki cross-coupling strategy as the key reaction step. [ABSTRACT FROM AUTHOR]

We report the chemical design and development of 3-aryl-substituted 7-alkoxy-4-methylcoumarins with enhanced fluorogenic properties. The 3-aryl substituents are installed via an optimized Suzuki–Miyaura cross-coupling (SMC) reaction between a 7-alkoxy-3-bromo-4-methylcoumarin and aryl boronic MIDA esters using Pd(OAc) 2 /XPhos in a catalytic system with K 2 CO 3 in aqueous THF. Under these conditions, an exocyclic ester functionality is found to be unaffected. Subsequent saponification revealed a carboxylic acid functionality that is suitable for conjugation reactions. Evaluation of their fluorescence properties indicated that the installed 3-heteroaryl substituent, particularly benzofuran-2-yl, resulted in a significant red shift of both the excitation and emission wavelengths. [ABSTRACT FROM AUTHOR]

A mild and selective protocol has been developed for the palladium-catalyzed phosphine-free Suzuki cross-coupling reaction of aryl bromides with arylboronic acids in aqueous tea extract at room temperature. It is noteworthy that the aqueous tea extract plays an important role in the reaction, and various functional groups are tolerated under the optimized conditions. The reactions proceeded with very good chemoselectivity in favor of the bromo instead of the chloro group even at higher temperatures. Furthermore, this protocol could be applied to the cross-coupling of 4-bromoindole without protecting the base sensitive amine group with arylboronic acids in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

The Tsuji-Trost reaction between diethyl malonate and allyl acetate catalyzed by palladium(II) NPN-aminoiminophosphoranate complexes yields mono- and diallylation products in the ratios depending on the complex used. The Suzuki-Miyaura cross-coupling of 4-bromoacetophenone with phenylboronic acid catalyzed by these palladium complexes proceeds with 66-99.5% conversions. [ABSTRACT FROM AUTHOR]

Condensation of o-(diphenylthiophosphoryl)aniline with 8-formyl-7-hydroxy-4-methylcoumarin yields the Schiff base capable of acting as a tridentate monoanionic ligand upon coordination with the Re and Pd ions. The corresponding palladium complex shows high catalytic activity in the Suzuki cross-couplings of aryl bromides with phenylboronic acid. The analogous P(O)-substituted ligand was not isolated in the pure form; however, using template-assisted method, its κ- O, N, O-zinc complex was synthesized; this complex is luminescent in the MeCN solution at 20 ℃. [ABSTRACT FROM AUTHOR]

Abstract: An efficient and scalable route for a series of novel substituted 2-anilino-7H-pyrrolopyrimidine compounds as potential inhibitors of PDK1, an important regulator of the PI3K/Akt pathway that is dysregulated in many cancers, was developed and is described. The synthetic strategy was designed around Suzuki and Buchwald–Hartwig cross-couplings of a boronate fragment and various customised anilines sequentially with 2,4-dichloro-7-tosyl-7H-pyrrolopyrimidine. All fragments were constructed separately and cross-coupled to provide access to a range of novel compounds. Biological evaluation of these was undertaken, with modest inhibition observed. [Copyright &y& Elsevier]

PDK1, a biological target that has attracted a large amount of attention recently, is responsible for the positive regulation of the PI3K/Akt pathway that is often activated in a large number of human cancers. A series of second-generation 2-anilino-4-substituted-7H-pyrrolopyrimidines were synthesised by installation of various functions at the 4-position of the 7H-pyrrolopyrimidine scaffold. All compounds were screened against the isolated PDK1 enzyme and dose response analysis was obtained on the best compounds of the series. [ABSTRACT FROM AUTHOR]

Abstract: In this work we report the synthesis of the complexes of the type [Cu(μ-Cl){Ph2P(CH2) n PPh2C(H)C(O)PhR}]2 (n = 1: R = Cl (1), NO2 (2); n = 2: R = Cl (3), NO2 (4)) derived from the reactions of the copper(I) chloride with related phosphorus ylides in equimolar ratios using dry methanol as solvent. The identity of complex 1 was unequivocally determined by single crystal X-ray diffraction techniques, its structure consisting of five-membered rings formed by coordination of the ligands through the phosphine group and the ylidic carbon atom to the metal center. The coordination geometry around the Cu atoms in this complex can be defined as slightly distorted tetrahedral. Characterization of the obtained compounds was also performed by IR, 1H, 31P and 13C NMR spectroscopy and analytical data indicated a 1:1 stoichiometry between the Cu(I) chloride and ylide. Well-defined phosphine bis-ylide Cu(I) complexes 1 and 3 were found to be an effective catalyst for the Suzuki coupling of various aryl halides including with 4-ethyl phenylboronic acid, giving the desired coupling products at low catalyst loading in moderate to good yields. Also, the antibacterial activities of DMSO-solved complexes were measured by disc diffusion method against 6 Gram positive and negative bacteria. All Cu(I) complexes exhibited antibacterial activities against bacteria tested especially Gram negative ones. [Copyright &y& Elsevier]

Abstract: A new pyrrole building block is described, which allows for the regiospecific synthesis of 2,3,5-trisubstituted pyrroles and 2,3,4,5-tetrasubstituted pyrroles. Optimization studies are presented for the preparation of the pyrrole building block along with the evaluation of various cross-coupling conditions and cross-coupling agents. A short, formal synthesis of the natural products Polycitone A, Polycitone B, and Polycitrin A from the pyrrole building block is also described. [Copyright &y& Elsevier]

Highlights: [•] Highly active magnetically separable nanocomposite catalysts. [•] A general platform to load variable nanocatalysts such as Pd or Pt. [•] Efficient reduction of nitroarenes and Suzuki cross-coupling reactions. [•] Large scale synthesis using a simple and economical process. [•] Catalysts recycling for five consecutive reactions. [ABSTRACT FROM AUTHOR]

Abstract: Five-membered P,C-palladacycles were synthesized through the reaction of the binuclear triphenylphosphite complex [Pd(μ-Cl)P(OPh)2(OC6H4)]2 (1) with different monodentate ligands [L=triphenylphosphine (PPh3), thiourea (tu), 2,4,6-trimethylpyridine (Me3Py), pyridine (Py)] and bidentate ligands [N^N=1,10-phenanthroline (Phen), 4-methyl-1,10-phenanthroline (MePhen)], giving mononuclear P,C-palladacycles [Pd(L)(Cl){P(OPh)2(OC6H4)}] [L=PPh3 (2a), tu (2b), Me3Py (2c)], [PyH]+[Pd(Cl)2{P(OPh)2(OC6H4)}]− (3d) and [Pd(N^N){P(OPh)2(OC6H4)}]+ NO3 − [N^N=Phen (4a), MePhen (4b)]. The synthesized complexes were characterized by 1H, 13C–{1H} and 31P–{1H} NMR spectroscopy, elemental analysis and FT-IR techniques. Structural details of complexes 2a, 2c and 3d were determined by X-ray crystallography, which showed these complexes crystallize in the triclinic (2a) and monoclinic (2c and 3d) crystalline systems. According to the structural data, the orthopalladated complex 3c has two different conformers (R,S) in the solid state, although it appeared as one isomer in the solution state, as confirmed by the NMR spectroscopy. Complex 2a, containing PPh3, was evaluated as a homogeneous catalyst for a variety of substrates, affording coupled products in good to excellent yields, importantly at room temperature. Furthermore, the use of the lesser reactive aryl chloride as a substrate in the Suzuki reaction under mild conditions, has received much attention. [Copyright &y& Elsevier]

Abstract: The development of a preparative route to a series of novel 4-(1H-indol-6-yl)-1H-indazole compounds as potential PDK1 inhibitors is described. The synthetic strategy centres on the late-stage Suzuki cross-coupling of N-unprotected indazole and indole fragments. The use of a monoligated palladium catalyst system was found to be highly beneficial in the cross-coupling reaction. The indazole and indole fragments were constructed by diazotisation/cyclisation and SNAr/reductive cyclisation sequences, respectively. [Copyright &y& Elsevier]

Highlights: [•] New PdNPs on carbon materials nanocatalysts were prepared and fully characterized. [•] The nanocatalysts were found to be highly active in the Suzuki coupling reaction. [•] The hybrid systems were re-used up to 10 times without any loss of activity in PEG. [•] Reaction media was found to influence strongly the re-use of the nanocatalysts. [ABSTRACT FROM AUTHOR]

Abstract: Investigation of the model atroposelective Suzuki reaction catalysed by chiral CN-palladacycles have shown that two types of catalytic cycle may operate simultaneously, with strong dependence of their contributions upon the palladacycle structure and conditions used. Dominant contribution of palladacycle retaining pathway was provided by the non-metallocene planar chiral iminate CN-palladacycle (R pl)-4a using as catalyst, in reaction performed in toluene under aerobic conditions with KF as a base, affording (S a )-2-methoxy-1,1′-binaphthalene with enantioselectivity up to 53% ee. The catalyst was recovered almost quantitatively as an iodide-bridged dimer, whose structure was confirmed by an X-ray diffraction study of its phosphine derivative. It was also shown that the common Hg drop test was unsuitable for mechanistic testing of palladacycle-catalysed reactions because of the transmetallation product formation, whose structure was confirmed by an X-ray diffraction study. [Copyright &y& Elsevier]

Highlights: [•] Mechanism of Pd-catalyzed Suzuki polycondensation was elucidated. [•] Transmetallation step is turnover determining in both initiation and propagation. [•] The (p-BrC6H4)Pd(t-Bu3P)I catalyst is better because of faster initiation. [•] Perfluorophenyliodide may be a more efficient initiator. [•] Boronic ester monomer is more active than boronic acid. [Copyright &y& Elsevier]

Highlights: [•] Pd and Pd-Au based catalysts were prepared by the sol–gel method and MCM-41suports. [•] The catalysts were evaluated for Suzuki reaction in air and without ligands. [•] The catalysts were evaluated for Suzuki reaction in water as solvent. [•] The catalytic behavior could be influenced by the nature of the catalyst employed. [•] The Au metal showed influence in the catalytic behavior. [Copyright &y& Elsevier]

Pd nanoparticles with narrow size distributions between 1.3 and 3.3 nm are prepared using G-/C-rich oligonucleotide as the template. These DNA-Pd nanoparticles efficiently catalyze the Suzuki coupling reaction and exhibit highly catalytic activities under mild conditions, which are greatly dependent upon the particle size of Pd nanoparticles besides the DNA sequence. For the coupling reaction of iodobenzene and phenylboronic acid at 60 °C in the presence of KOH, it can be achieved high TOF value of 2646 mol biphenyl (mol Pd × h) over AG22-Pd and 3640 mol biphenyl (mol Pd × h) over CT22-Pd. Under the optimal experimental conditions, the yield of 100 % in biphenyl is obtained with only 0.0055 mol% AG22-Pd at 60 °C for 1 h in the solvent of EtOH/HO (1:2) using NaCO or KCO as the base. It is illustrated that G-/C-rich oligonucleotides are promising templates to modulate easily the morphology of Pd nanoparticles in aqueous solution with high catalytic activity. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Three periodic mesoporous materials, i.e., two organosilicas with either ethylene or phenylene bridges and one silica, have been used as supports for Pd nanoparticles. All Pd-supported samples (1.0 wt%) were prepared by the incipient wetness method and subsequently reduced in an H2 stream at 200 °C. Both hydrogen chemisorption and temperature programmed reduction experiments revealed significant differences depending on the support. Pd2+ species were more reducible on the mesoporous organosilicas than on their silica counterpart. Also, remarkable differences on the particle morphology were observed by transmission electron microscopy. All Pd-supported samples were active in the Suzuki cross-coupling reaction between bromobenzene and phenylboronic acid. [ABSTRACT FROM AUTHOR]

Come into the light: Pyrimidine nucleosides were found to undergo fast and reversible ring closure upon irradiation with light when covalently attached to 2‐[2‐methyl‐5‐phenylthien‐3‐yl]cyclopent‐1‐ene (see scheme). Synthesis using an aqueous‐phase Suzuki–Miyaura cross‐coupling allows for one‐step conversion of iodo‐modified oligonucleotides into fully reversible DNA photoswitches. [ABSTRACT FROM AUTHOR]

A short synthesis of marinoquinolines C and E has been achieved. The synthetic route involves an ipso nitration of an electron-deficient boronic acid, the first example of a Bartoli indolization on a nitroquinoline and Suzuki coupling between 2-chloropyrroloquinoline and two separate MIDA boronates. [ABSTRACT FROM AUTHOR]

Abstract: For the first time, Suzuki cross-coupling reactions were used for introducing an aromatic group in position 8 of the pyridine ring of novel pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidin-4-amines. This reliable and simple method may be extended to various boronic acids for allowing preparation of a larger library of these compounds in the hope of further structure–activity relationship investigations. [Copyright &y& Elsevier]

A new synthetic pathway was devised to reach tetrasubstituted 3-arylthiophene 2-carboxylic acids in a three-step solid-phase synthesis. This very efficient methodology provided more than 20 new compounds that were evaluated for their ability to inhibit protein farnesyltransferase from different species as well as Trypanosoma brucei and Plasmodium falciparum proliferation. [ABSTRACT FROM AUTHOR]

Abstract: An efficient pathway to synthesize biaryls and terphenyls through ligand-free palladium nanoparticles (PdNPs) catalyzed Suzuki cross-coupling reactions has been developed. Mild reaction conditions, high yields of desired products, absence of inert atmosphere and short reaction times are the notable features of this method. [Copyright &y& Elsevier]

Abstract: Variation at the 3’ position of fluorescein via Suzuki–Miyaura cross-coupling with aryl and heteroaryl moieties gave a family of anthofluoresceins whose spectroscopic properties were studied. The 1-methylindole derivative gave the highest quantum yield and was observed to behave as a molecular rotor, displaying marked variations in fluorescent intensities with viscosity and offering possible application in cellular sensing and fluorescent polarisation assays. [Copyright &y& Elsevier]

Coupling quinoline at its 5,8-positions provides a facile way to copolymerize quinoline with other conjugated moieties without breaking conjugation. Model compounds containing quinoline units, either at the periphery or in the core, were synthesized and one of them was characterized by X-ray diffraction. Copolymers of quinoline and 9,9-dialkylfluorene (R = n-octyl or 2-ethylhexyl) were synthesized in good yield by palladium-catalysed Suzuki cross-coupling. The copolymers are highly soluble in common organic solvents and gel permeation chromatography measurements against polystyrene standards showed the number-average molecular weight to be in the range (1.02-2.06) × 104 g mol−1. Both copolymers emit in the blue region with an emission maximum centred at 435 nm. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A complex of [BMIm] PF6 (1-Butyl-3-methylimidazolium hexafluorophosphate) with PEG1000 has been successfully applied and found to be efficient for Suzuki cross-coupling and Heck reaction using Pd(OAc)2 as the catalyst under air atmosphere. Moreover, the isolation of the products is readily performed by the extraction of diethyl ether, and the catalytic system reported here can be recycled and reused several times. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: A novel highly efficient monodentate imine palladium catalyst system has been tested for Suzuki cross-coupling reaction. Under the standard conditions, a series of aryl halides, including phenyl iodide, aryl bromides and phenyl chloride, were coupled with phenylboronic or 1-naphthylboronic acid, producing the corresponding biaryls in good to excellent yields. High-resolution transmission electron microscopy (HR-TEM) study of the recycled catalyst showed the formation of palladium nano particles in the catalytic system. [Copyright &y& Elsevier]

Abstract: 3,5-Diferrocenylpyridine was synthesised from 3,5-dibromopyridine and ferroceneboronic acid, in respectable yield (48%), using a microwave-enhanced Suzuki cross-coupling reaction. This novel ligand and its palladium(II) dichloride complex have been fully characterised using elemental analysis, HR–ESI-MS, IR, UV and NMR spectroscopy. Additionally, the molecular structures of 3,5-diferrocenylpyridine and [Pd(3,5-diferrocenylpyridine)2Cl2] were confirmed by X-ray crystallography. A comprehensive study of the electrochemistry of 3-ferrocenylpyridine, 3,5-diferrocenylpyridine and their palladium(II) dichloride complexes was performed using traditional hexafluorophosphate and weakly-coordinating fluorinated aryl borate anions. Electronic communication between the two proximal ferrocenyl centres of 3,5-diferrocenylpyridine and its palladium complex is only observed when the weakly-coordinating fluorinated aryl borate anions are used as the supporting electrolyte. [Copyright &y& Elsevier]

The paper describes the Suzuki cross-coupling of a variety of N and C-3 substituted 5-bromoindazoles with N-Boc-2-pyrrole and 2-thiopheneboronic acids. The reactions, performed in the presence of K2CO3, dimethoxyethane and Pd(dppf)Cl2 as catalyst, gave the corresponding adducts in good yields. The methodology allows the facile production of indazole-based heteroaryl compounds, a unique architectural motif that is ubiquitous in biologically active molecules. [ABSTRACT FROM AUTHOR]

The cycloparaphenylenes (CPPs) are fully aromatic nanohoops consisting solely of para-linked benzene rings. While these unique structures were first envisioned over 70 years ago, they have only recently been prepared in the laboratory. This work highlights important historical approaches towards the CPP class of molecules, the recent flurry of successful syntheses of a variety of CPPs, and our synthesis of the most strained cycloparaphenylene thus far, [7]CPP. [ABSTRACT FROM AUTHOR]

Representative glycerol derivatives were employed as green solvents for selected organic transformations. In all reactions it was found that both reaction performance and product extraction yields were affected by solvent type and polarity. The solubility of the substrates in the solvent was the key step in product yield determination, while the product solubility in the reaction solvent determined the effectiveness of its extraction. [ABSTRACT FROM PUBLISHER]

Abstract: Sphos (2-dicyclohexylphosphino-2′,6′-dimethoxy-1,1′-biphenyl) adduct of cyclopalladated ferrocenylimine (IIe) exhibited highly catalytic activity for the Suzuki cross-coupling reaction of cyclopropylboronic acid with aryl(het) halides with 1mol % catalyst loading. This process was applied to both of aryl and heteroaryl halides (Br and Cl), and made the various arylcyclopropane and heteroarylcyclopropane to be easily synthesized. A variety of substituents on the aryl halides, such as alkyl, acetyl, benzoyl, ether, formyl, carboxylate, methoxy, nitro and cyano were tolerated. [Copyright &y& Elsevier]

Apoptotic induction mechanisms are of crucial importance for the general homeostasis of multicellular organisms. In cancer the apoptotic pathways are downregulated, which, at least partly, is due to an abundance of inhibitors of apoptosis proteins (IAPs) that block the apoptotic cascade by deactivating proteolytic caspases. The Smac protein has an antagonistic effect on IAPs, thus providing structural clues for die synthesis of new-pro-apoptotic compounds, Herein, we report a solid-phase approach for the synthesis of Smac-derived tetrapeptide libraries, On the basis of a common (N-Me)AVPF sequence, peptides incorporating triazoloprolines and biarylalanines were synthesized by means of Cc(I)-catalyzed azide-alkyne- tycloacldition and Pd-catalyzed Suzuki cross-coupling reactions, Solid-phase procedures were optimized to high efficiency, thus accessing all products in excellent crude purities ant! yields (both typically above 90%). The peptides were subjected to biological evaluation in a live/dead cellular assay which revealed that structural decorations on the AVPF sequence indeed are highly important for cytotoxicity toward Hela cells. [ABSTRACT FROM AUTHOR]