Cu(OAc)_2 catalyzed Sonogashira cross-coupling reaction in amines

A simple Cu（OAc）2 catalyzed Sonogashira coupling protocol is presented. It was found that the couplings of a variety of aryl halides with terminal alkynes were conducted smoothly to afford the corresponding desired products in moderate to excellent yields, using Cu（OAc）2 as the catalyst and Et3N as the solvent.

Polybinaphthyls of (R)-3,3′-Diiodo-2,2′-binaphtho-20-crown-6 with p-Divinylbenzene via Heck Cross-coupling Reaction

The present paper deals with the polymerization of ( R ) 3,3′ diiodo 2,2′ binaphtho 20 crown 6 with \{ p divinylbenzene\} under Heck coupling reaction condition. Both the monomers and the polymer were analyzed by NMR, FTIR, UV, CD, fluorescent spectroscopy, polarimetry, GPC and elemental analysis. The polymer can emit a strong blue fluorescence and is expected to have the potential application in the polarized blue light emitting sensors. The chiral conjugated polymer exhibits a strong Cotton effect in its Circular Dichroism(CD ) spectrum, indicating the high rigidity of the polymer backbone.

LOW-VALENT TITANIUM INDUCED REDUCTIVE CROSS-COUPLING REACTION OF ESTERS WITH DIARYL KETONES

The intermotecular coupling reaction of esters with diarvl ketones induced by titanium tetrachtoride and zinc powder was studied.

LOW-VALENT TITANIUM INDUCED REDUCTIVE CROSS-COUPLING REACTION OF ACYL CHLORIDES WITH DIARYL KETONES

Treatment of acyl chlorides and diaryl ketones with an activated Ti(o)reagent,prepared by reduction of TiCl_4 with Zn powder,effects an intermolecular reductive cross-coupling reaction leading to ketones.

Preparation of polymer-supported phosphine from ferrocene for palladium-catalyzed Suzuki-Miyaura cross-coupling reactions

Polymer-supported phosphine ligand 3b derived from ferrocene was prepared, and applied in palladium-catalyzed Suzuki- Miyaura reactions. A range of aryl bromides can couple with phenylboronic acid to obtain corresponding biaryls in excellent yields. The recycling of the polymer-bound catalyst was tested without adding palladium.

Aryl-guanidine/Pd-catalyzed Suzuki Cross-coupling Reaction at Room Temperature

Four aryl-guanidines（AG） were synthesized and used for the palladium-catalyzed Suzuki cross-coupling reaction to test the catalytic activity.In the presence of steric bulk AG,when aryl bromide and arylboronic acid were used as the reactants,the Suzuki reaction could be carried out smoothly at room temperature in aqueous solvent to afford the cross-coupling product in high yield.This catalysis system was also successful for the coupling of activated aryl chlorides at room temperature.

Microwave-assisted Palladium-micelle-catalyzed Suzuki Cross-coupling Reaction in Water

A microwave-accelerated Suzuki coupling procedure was developed via guanidinium ionic liquids（GILs） stabilized Pd-micelle.The Pd micelle/GILs play a key role in enhancing the activity,due to the highly dispersed Pd active sites and the phase transfer function of GILs,which ensures the adsorption of reactants and facilitates the translation of the intermediates to the surface of the micelle.

Novel Stereoselective Synthesis of 1,3-Dienyl Tellurides by Palladium Catalyzed Cross-coupling Reaction of (E)-β--Bromovinyl Tellurides

β-Bromovinyl tellurides are new difuctional reagents which undergo palladium-catalyzed cross-coupling reaction with alkenes to give conjugated dienyl tellurides.

Efficient Cross-Coupling Reaction of Aryltrifluoroborates and Aroyl Chlorides for the Synthesis of Fluorine Substituted Aromatic Ketones

The direct aroylation of ArCOPdCl with potassium aryltrifluoroborates establishes a new cross-coupling synthetic tool for the synthesis of various fluorine substituted benzophenones. The new microwave irradiated process is very efficient and produce high yield benzophenone products within minutes.

Ultrasonic Activation of Suzuki and Hiyama Cross-Coupling Reactions Catalyzed by Palladium

The coupling reaction of aryl bromide and aryl boronic acid in water/DMF as solvent was studied using a palladium-complex as a catalyst in the presence of ultrasound at room temperature. The effect on the reaction of a base and a solvent was also studied with and without ultrasound and was found to increase the speed of the reaction. In this regard, we propose reaction mechanisms that could explain the results obtained.

High-efficiency PdNi single-atom alloy catalyst toward cross-coupling reaction

The preparation of Pd-based catalysts with rich electrons and a high atom dispersion rate is of great significance for improving the reactivity of cross-coupling reactions,which is a powerful tool for pharmaceutical and fine chemical synthesis.Here,we report a PdNi single-atom alloy(SAA)catalyst in which isolated Pd single atoms are anchored onto the surface of Ni nanoparticles(NPs)applied for Suzuki coupling reactions and Heck coupling reactions.The 0.1%PdNi SAA exhibits extraordinary catalytic activity(reaction rate:17,032.25 mmol h^(-1)gPd^(-1))toward the Suzuki cross-coupling reaction between 4-bromoanisole and phenylboronic acid at 80℃for 1 h.The excellent activity is supposed to attribute to the 100 percent utilization rate of Pd atoms and the highly stable surface zero-valance Pd atoms,which provides abundant sites and electrons for the adsorption and fracture of the C-X(X=Cl,Br,I)bond.Moreover,our work demonstrates the excellent application prospect of SAAs for cross-coupling reactions.

In situ monitoring of Suzuki-Miyaura cross-coupling reaction by using surface-enhanced Raman spectroscopy on a bifunctional Au-Pd nanocoronal film

Surface-enhanced Raman spectroscopy(SERS), a powerful surface vibrational spectroscopic technique, is ideally suited for in situ monitoring the chemical transformations occurred at surfaces and/or interfaces.For in situ SERS monitoring, a platform integrated both plasmonic and catalytic activity is a prerequisite. Here, we fabricate a bifunctional Au-Pd nanocoronal film for in situ SERS monitoring Suzuki-Miyaura cross-coupling reaction. This excellent bifunctional substrate leads to the coupling of high catalytic activity with a strong SERS effect at the center of two adjacent Au cores and shows fine reproducibility and stability of SERS signals. During investigating the Suzuki reaction with in situ SERS, we found two distinct catalytic kinetic processes resulted from two disparate catalytic sites on a Au-Pd nanocoronal. Comparing with conventional analytical techniques, this work provides a novel approach for studying Suzuki reactions at surfaces and/or interfaces with in situ SERS.

Cu/photoredox-catalyzed decarboxylative radical C(sp^(3))–C(sp^(3))cross-coupling reactions

A radical decarboxylative C(sp^(3))–C(sp^(3))cross-coupling of NHPI esters and cyclopropanols was developed by combining photocatalysis and copper catalysis,which presents the efficient access toβ-benzyl ketones in excellent yields.Terpyridin-4′-one used as the ligand is vital for the reaction,which could facilitate the capture of benzylic radicals by alkyl-copper species generated from copper-catalyzed ring-opening of cyclopropanols.The reaction exhibited broad substrate scope and wide functional group compatibility,providing an alternative approach for C(sp^(3))–C(sp^(3))bond formation.

Arylhydrazones Derivatives Containing a Benzothiazole Moiety, Efficient Ligands in the Palladium-Catalyzed Mizoroki-Heck and Suzuki-Miyaura Cross-coupling Reactions under IR Irradiation

A simple arylhydrazone containing the benzothiazole moiety which may be used as an efficient ligand in the palladium-catalyzed Mizoroki-Heck and Suzuki-Miyaura cross-coupling reactions, under infrared irradiation as an alternative source of energy, is presented. The reactions proceeded with extremely high efficiency under mild conditions and produced very good yields.

Palladium-phosphinous acid complexes catalyzed Suzuki cross-coupling reaction of heteroaryl bromides with phenylboronic acid in water/alcoholic solvents

Highly active, air-stable and water-soluble palladium-phosphinous acid complexes have been applied to Suzuki cross-coupling reaction of heteroaryl bromides under mild conditions in water/alcoholic solvents. Suzuki cross-coupling reaction of heteroaryl bromides with phenylboronic acid occurred efficiently using palladium phosphinous acid complexes （POPd） and phase transfer catalyst （tetrabutylammonium bromide and polyethylene glycol） in water/ethanol mixture, water/propanol mixture and neat water respectively, the corresponding yields of cross-coupling heteroaryl-aryls were satisfied. The tert-butyl substituted ligand di-tert-butylphosphino in combination with POPd was found to be more active than the same family derived catalysts dipalladium complexes POPdl and POPd2, and other two kinds of Pd-catalysts Pd（PPh3）4 and Pd2（dba）3. The mechanism of Suzuki cross-coupling reaction between heteroaryl bromides and phenylboronic acid in water was proposed with respect to the key role of phase transfer catalyst on the transmetallation step. Compared with other solid phase transfer catalysts, TBAB was tested as the ideal one. The alkalinity of base and the molar proportion between POPd and TBAB were investigated in water and alcoholic solvents. Notably, in the presence of TBAB adding alcoholic solvents into water enhanced the yields of target products. However in terms of the liquid phase transfer catalyst of PEGs, mixing water into PEGs could slightly decrease the yields with respect to the water free PEGs bulk phase, which was probably due to the homogenous liquid conditions in pure PEGs and weak interactions between PEGs and heteroaryl bromide molecules in water depending on their molecular chain lengths.

2-Aminopyridine functionalized cellulose based Pd nanoparticles： An efficient and ecofriendly catalyst for the Suzuki cross-coupling reaction

A palladium catalyst supported on 2-amino- pyridine functionalized cellulose was synthesized and fully characterized by inductively coupled plasma atomic emission spectroscopy, transmission electron microscope, Fourier transform infrared spectroscopy, thermogravi- metric analysis and X-ray photoelectron spectrometry. This catalyst can be applied in the Suzuki cross-coupling reaction of aryl halides with arylboronic acids in 50% ethanol to afford biaryls in good yields, and easily recycled by simple filtration after reaction without the loss of metal Pd.

Efficient synthesis of 4-substituted pyrazole via microwave-promoted Suzuki cross-coupling reaction

Pyrazoles and their derivatives are important heterocycles found in nature and present in numerous bioactive compounds.In contrast to 3 or 5-aryl pyrazole,the preparation of 4-aryl pyrazole is fairly rare.Utilizing microwave irradiation,the synthesis of 4-substituted-arylpyrazole via Suzuki cross-coupling has been developed with a wide range of substrates.The remarkable advantages of this method are mild reaction conditions,simple operation,high yield,and short reaction time.Product structures were identified by MS 1H NMR 13C NMR,and elemental analysis.

Cu（OAc）2/Pyrimidines-Catalyzed Cross-coupling Reactions of Aryl Iodides and Activated Aryl Bromides with Alkynes under Aerobic, Solvent-free and Palladium-free Conditions

Excellent results have been achieved in the Cu（OAc）2-catalyzed Sonogashira cross-couplings of aryl iodides and activated aryl bromides utilizing TBAF （tetrabutylammonium fluoride） as the base and 4,6-dimethoxypyrimidin-2-amine as the ligand. It is noteworthy that the reaction is conducted under aerobic, solvent-free and palladium-free conditions.