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An efficient and generally applicable protocol for palladium-catalyzed oxidative deacetonative coupling of 4-aryl-2-methyl-3-butyn-2-ols with dialkyl H-phosphonates has been developed. This methodology provides a new and practical route to alkynylphosphonates using the inexpensive 4-aryl-2-methyl-3-butyn-2-ols as the alkyne sources. This reaction could also be performed with aryl bromides, 2-methyl-3-butyne-2-ol and dialkyl H-phosphonates using the cheap 2-methyl-3-butyne-2-ol as an alkyne source.

Pd(II)-catalyzed C-H sulfonylation of azobenzenes with arylsulfonyl chlorides has been developed. The sulfonylazobenzenes were obtained in moderate to excellent yields for 28 examples. This protocol features high efficiency, wide functional group tolerance, and atom economy.

The first catalytic and enantioselective C-H direct acylation of ferrocene derivatives has been developed. A series of 2-acyl-1-dimethylaminomethylferrocenes with planar chirality were provided under highly efficient and concise one-pot conditions with up to 85% yield and 98% ee. The products obtained could be easily converted to various chiral ligands via diverse transformations.

A novel protocol to synthesize tert-butyl esters from boronic acids or boronic acid pinacol esters and di-t-butyl dicarbonate has been successfully achieved. The cross-coupling reactions can produce up to 94% yields by using palladium acetate and triphenylphosphine as catalyst system, dioxane as a solvent. Moreover, a wide range of substrates including benzenes, pyridines, and quinolines boronic acids or boronic acid pinacol esters can fit with this system as well.

A highly efficient and practical procedure to acylazobenzene via Pd-catalyzed oxidative C-H bond activation from toluene has been developed. Various mono- and diacylazobenzene were afforded simultaneously in moderate to excellent yields for 33 examples. Toluene and its derivatives were served as potential and ideal acylation reagents. The mono- and diacylated products could be controlled by the oxidant loading.

An efficient phosphine-free direct C-H arylation of thiophenes at the α-position has been developed at low catalyst loading of bis(alkoxo)palladium complex (Cat.I, 0.1-0.2 mol %). The developed synthetic method can be applied to the synthesis of α-aryl/heteroaryl thiophenes from aryl or heteroaryl bromides in good to excellent yields and is compatible with the substrates bearing electron-donating or electron-withdrawing groups. The reactivities of the 2- and 5-positions of thiophenes are equivalent and not dependent on steric hindrance under optimal conditions. This condition can also be applied to other heterocyclic moieties such as benzothiophene, benzofuran, and pyrrole with high conversion yields.

A novel Pd(II)-catalyzed dehydrogenative cross-coupling reaction between coumarins and H-phosphonates has been developed to give the corresponding 3-phosphonated products in moderate to good yields with high selectivity.

This research provides a novel approach for introducing a CF3CH2 group onto aromatic rings using Pd(OAc)2/palladacycle as a catalyst for the Suzuki cross-coupling reaction of CF3CH2OTs (OTs = 4-methylbenzene sulfonate) with arylboronic acids.

A facile and efficient protocol for palladium-catalyzed ortho-acylation of 2-aryl pyridines was developed. Note that this acylation utilized arylmethyl amines as new, cheap and readily available acylation reagents and exhibited high regioselectivity for 2-aryl pyridines bearing a meta-substituent in the aryl ring moiety.

A highly efficient and practical protocol for palladacycle-catalyzed decarboxylative coupling of alkynyl carboxylic acids with aryl chlorides was developed. The reaction could proceed smoothly in air within 3 h under optimized reaction conditions (1 mol % of palladacycle, 4 mol % of Xphos, 2.0 equiv of K2CO3 in xylene/H2O), affording the corresponding internal alkynes in mostly good to excellent yields. Remarkably, this result represents the first successful examples of this type of decarboxylative cross-coupling using electron-poor, electron-neutral and even inactive sterically hindered electron-rich aryl chlorides as the starting materials.

The cross-coupling reactions of 1,1,1-trifluoro-2-iodoethane with aryl and heteroaryl boronic acid esters have been successfully achieved. The new protocol allows for a convenient introduction of trifluoroethyl groups into a variety of aryl and heteroaryl moieties under mild conditions.

N,N-Dimethylaminomethyl ferrocenium could be generated in situ and served as a terminal oxidant for Pd-catalyzed directly dehydrogenative annulations of N,N-dimethylaminomethyl ferrocene and internal alkynes. This procedure utilized the redox activity of ferrocene and avoided adding an oxidant. A series of highly arylated naphthalenes functionalized by ferrocene were obtained in 53-81% yields.

The direct cross-coupling of quinoline-N-oxides with olefin derivatives has been realized using palladium acetate as the catalyst in the absence of external ligand and oxidant to give the corresponding 2-alkenylated quinolines and 1-alkenylated isoquinolines chemo- and regioselectively in 27-95% yield. The catalytic process is proposed to proceed via direct C-H bond activation of the quinoline-N-oxide with Pd(OAc)(2) followed by Heck coupling with the olefin. The resultant N-oxide of the alkenylated quinoline can oxidize the reduced Pd(0) to regenerate the Pd(II) active species and simultaneously release the 2-alkenylated quinoline without using any external oxidants and reductants.

The one-pot, palladium-catalyzed, three-component coupling of aryl bromides, internal alkynes, and environmentally friendly K4[Fe(CN)6] provides an efficient and direct method for the preparation of beta-arylalkenylnitriles.

Both conventional heating and ultrasound effect on the cyclopalladated ferrocenylimines catalyzed Suzuki reaction of phenylboronic acid with a range of arylhalides in neat water was investigated. Heterogenous reaction of electron-withdrawing arylchlorides with phenylboronic acid could also result in good yields by using Cat. 2. It was found that the ultrasonic irradiation could dramatically accelerate the Suzuki reaction to achieve comparable results.

The palladium‐catalyzed enantioselective C−H alkenylation of ferrocenecarboxylic acid has been developed. A series of 2‐alkenyl ferrocenecarboxylic acids with planar chirality were obtained using molecular oxygen as an oxidant. This protocol starts from less expensive and readily available starting materials and provides the target products as a key intermediate in organic synthesis. [ABSTRACT FROM AUTHOR]

A chemoselective, palladium-catalyzed, ligand-directed ortho-CH chlorination and acylation process has been developed, exhibiting high regioselectivity for 2-arylpyridines bearing a meta-substituent. Worthy of note is the fact that arylmethyl chlorides as new, readily available, and inexpensive reagents can selectively be utilized as chlorine or acyl sources. [ABSTRACT FROM AUTHOR]

A highly efficient and convenient palladium catalyzed the ortho-acylation of azoxybenzenes has been developed. Easily available aldehydes were used as a cheap and ideal aroyl sources. This method provides a practical and direct pathway to synthesize 2-acylated azoxybenzenes in chemo- and regioselective manners via palladium-catalyzed CH bond activation. Various substituents on both coupling partners are tolerated well. [ABSTRACT FROM AUTHOR]

An efficient and practical decarboxylative double benzylation method for various 2-picolinic acids has been established by using a bimetallic catalytic system of palladium(II) chloride (PdCl2) and silver(I) oxide (Ag2O), which offered a variety of diarylmethane derivatives with moderate to good yields. [ABSTRACT FROM AUTHOR]

The first palladium-catalyzed protocol for the denitrated of nitroarenes with phenols has been developed, achieving unsymmetrical diaryl ethers in moderate to excellent yields. The cyclopalladated ferrocenylimine (catalyst Ic) exhibited highly for this transformation with low catalyst loading (0.75 mol%) and short reaction time (2 h). The efficiency of this reaction was demonstrated by its compatibility with a range of groups. Moreover, the rigorous exclusion of air or moisture was not required in these transformations. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A series of cyclopalladated arylimine self-assembly films were prepared through chemical grafting to substrates and used to catalyze a Suzuki coupling reaction. Atomic force microscopy, water contact angle analysis, cyclic voltammetry, scanning electron microscopy, attenuated total-reflectance infrared, and X-ray photoelectron spectroscopy were used to analyze the morphology and composition of the heterogeneous catalysts. The results show that these cyclopalladated arylimine self-assembly films immobilized on substrates could be used as efficient and reusable heterogeneous catalysts in the Suzuki reaction of aryl bromides under open air conditions in aqueous solution. These catalysts exhibited 10 times the catalytic performance of the homogeneous counterpart. The palladium catalysts were grafted onto the internal surface of the round-bottomed flasks. The reaction flasks acted as both reaction vessels and catalysts, which simplified the reaction operations. The catalysts were run over 8 cycles without showing any sign of deactivation, suggesting the potential of the catalysts as advanced functional materials with applications in the heterogeneous catalysis of Suzuki reactions. [ABSTRACT FROM AUTHOR]

An efficient and generally applicable protocol for the palladacycle-catalysed arylation or K2CO3-promoted arylmethylation of diisopropyl H-phosphonate has been developed. The remarkable features of the palladacycle-catalysed arylation reaction include wide substrate scope (aryl iodides, bromides and chlorides), significant shortening of the reaction time (2 or 3 h) and a low catalyst loading of 1 mol-%. Note that with the base K2CO3 as promoter, arylmethylation could be achieved without any palladium catalyst. Moreover, the first example of a palladium-catalysed phosphonation of inactive electron-rich aryl chlorides with tBuOK as the base has been realized. This result could be considered an important improvement and complement to earlier work of Montchamp and Han, whose catalytic systems are typically compatible with electron-deficient and electron-neutral aryl chlorides. [ABSTRACT FROM AUTHOR]

Abstract: A new and highly regioselective arylation of 2-arylbenzoxazoles based on C–H activation has been developed. The results represent the first examples of palladium-catalyzed direct ortho-arylation of 2-arylbenzoxazoles and also provide a facile route for the synthesis of complicated structures containing arylated benzoxazoles moieties. [Copyright &y& Elsevier]

The direct ring construction of amides with alkynes catalyzed by palladium acetate with cheap oxidant under an air atmosphere has been realized. A variety of novel highly substituted naphthalenes 3a–3lhave been prepared chemo- and regioselectively in 55–97% yields under mild conditions. Product 3jemits intense blue luminescence peaked at 435 nm with a good blue purity. [ABSTRACT FROM AUTHOR]

The first diastereoselective synthesis of β-amino ketone and β-amino acid derivatives by palladium-catalyzed conjugate addition of arylboronic acids to chiral β-enamino ketones and β-enamino esters is reported. The catalytic system employing (S)-4-( tert -butyl)oxazolidin-2-one as the chiral auxiliary in water under an air atmosphere provides β-amino ketone and β-amino acid derivatives in high yields with excellent diastereoselectivity. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed diastereoselective synthesis of optically active β,β-diarylpropionic acid derivatives employing 4-( tert -butyl)oxazolidin-2-one as the chiral auxiliary under an air atmosphere in excellent yields with high diastereoselectivity is reported. The catalytic system is applied to the total synthesis of ( R )-tolterodine and the enantiomer of a key intermediate for MK-8718. [ABSTRACT FROM AUTHOR]

An efficient protocol for the synthesis of 1-heteroaryl-4-( N -methyl)aminopiperidines starting from heteroaryl chloride derivatives is described. A broad range of 1-heteroaryl-4-( N -Boc- N -methyl)aminopiperidine derivatives were obtained in good to excellent yields using DavePhos as optimal ligand for Pd-catalyzed Buchwald-Hartwig amination reaction. After a mild and efficient acidolysis the amination products could be obtained successfully. [ABSTRACT FROM AUTHOR]

Ensemble synergistic effect between the metals, ligand and support were that electron transferred from GO via ligand to Pd and, then to Cu to Pd to made Pd more negative, resulting in a higher activity. [Display omitted] • A new aryl triimine bimetallic catalytic molecular monolayer was fabricated. • GO@T-Pd 0.01 /Cu 0.99 exhibited high catalytic activity with a higher TOF (118588 h−1). • Hybrid of Cu enhanced the electronegativity of Pd by synergistic between Pd and Cu. A new aryl triimine palladium-copper bimetallic catalytic molecular monolayer anchored on graphene oxide (denoted as GO@T-Pd 0.01 /Cu 0.99) was fabricated by self-assembly and characterized by XRD, Raman, FT-IR, XPS, SEM, TEM, ICP-AES and AFM. Its catalytic performance, stability and catalytic mechanism were investigated by using Suzuki coupling reaction as a template. GO@T-Pd 0.01 /Cu 0.99 exhibited high catalytic activity for iodo aromatics and brominated aromatics with a higher TOF (118588 h−1) and could be recycled for 6 times without significant loss of activity. Heterogeneous catalytic mechanism was investigated in detail by kinetic and thermal filtration experiments, catalyst poisoning experiments and XPS, with which heterogeneous catalytic process occurred at the interface of catalytic monolayer could be confirmed. Hybrid of non-precious metals enhanced the electronegativity of Pd by synergistic between Pd and Cu, thereby improving their catalytic activity and stability of the catalyst. The deactivation mechanism of GO@T-Pd 0.01 /Cu 0.99 was the accumulation and loss of active centers during catalytic process. [ABSTRACT FROM AUTHOR]

Abstract: Both nitrile and arylamino groups containing pyridine derivatives are synthesized from commercially available nitrile substituted pyridyl chlorides via a palladium–BINAP catalyst (the second generation catalyst for the amination) in moderate to good yields. The mild conditions permit the presence of base sensitive functional groups. Noteably, the halogen atoms linked to the aromatic ring were maintained in the structures of the products under the amination reaction conditions. [Copyright &y& Elsevier]

Abstract: A mild and efficient method for oxidative Heck-type reaction of arylboronic acids with olefins catalyzed by cyclopalladated ferrocenylimine was developed. The results represent the first examples involving the palladacycle as the catalyst for such couplings. Moreover, the catalytic system could tolerate various functional groups, such as F, Cl, Br, NO2 and CH3O, and the substrates could be extended to a wide range of olefins from acrylic esters, α,β-unsaturated ketones to alkenes. Furthermore, the olefination could proceed well under base- and ligand-free conditions and employ oxygen as the environmentally benign oxidant. [Copyright &y& Elsevier]

A polymer (fiber)-supported palladium catalyst was synthesized simply from commercially available polyacrylonitrile(PAN) fiber. Its high activity and selectivity for Heck reactions were measured; its activity remained unchanged after being recycled 20 times. [Copyright &y& Elsevier]

A catalytic system comprised of a bis(alkoxo)palladium complex and Xantphos is tested in the heteroarylation of 2-methylthiophene (I) and heteroarenes (VI). [ABSTRACT FROM AUTHOR]

This facile protocol allows the direct ortho-acylation of azoxybenzenes with good tolerance for a variety of functional groups in both reaction partners. [ABSTRACT FROM AUTHOR]

Halogenated nitroarenes like (VII) react via nucleophilic displacement of the halogen atom under the present conditions. [ABSTRACT FROM AUTHOR]

The title reaction uses a bimetallic catalytic system consisting of PdCl2 and Ag2O. [ABSTRACT FROM AUTHOR]

A novel protocol of palladacycle-catalyzed denitrated coupling of nitroarenes (I) with phenols (II) is described leading to unsymmetrical diaryl ethers (III) (37 examples) in moderate to high yields. [ABSTRACT FROM AUTHOR]

A bis(N,N-diethanolamine)palladium complex is successfully used as catalyst for the oxidative Heck reaction between a variety of alkenes and arylboronic acids. [ABSTRACT FROM AUTHOR]

The catalyst is grafted onto the internal surface of the round-bottomed flask which serves as a reaction vessel and a catalyst. [ABSTRACT FROM AUTHOR]