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PAVs. The availability of substrates, as well as simplicity of the method, are favorable features of this protocol. Another example of Hiyama coupling leading to the synthesis of ( E ) or ( Z )-oligo(arylene vinylenes) is the Pd-coupling reaction of 1,4-diiodobenzenes with 1,4-bis(silylethenyl)benzenes [ 32 ]. The Suzuki coupling, which is the most commonly used method for the formation of new carbon-carbon bonds, is used also in the formation of PAVs. Oligo(arylene vinylenes) or PAVs obtained according to the Suzuki coupling, due to the retention of the

Introduction Chromones (4 H -1-benzopyran-4-ones) are naturally occurring oxygen-containing heterocyclic compounds, which perform important biological functions in nature [1] and are a recognized pharmacophore of a large number of bioactive molecules of either natural or synthetic origin. Their derivatives are antibacterial, anticancer, antioxidant, estrogenic agents [2–4], and have been considered as privileged structures in drug development [5]. The Suzuki coupling reaction is the palladium catalyzed C-C bond formation reaction of organoboran compounds with

Abstract

A new palladium-bidentate complex [m-C6H4(CH2ImMe)2(PdCl2)] (III) was prepared in two steps. In the first step, [m-C6H4(CH2ImMeAgCl)2] (II) (Im = imidazole moiety) was obtained by reacting imidazolium salt [m-C6H4(CH2ImMe)2]Cl2 (I) (prepared by quaternisation of Nmethylimidazole with 1,3-bis(chloromethyl)benzene) and Ag2O in CH2Cl2. In the next step, treatment of (II) with Pd(CH3CN)2Cl2 afforded complex III which was evaluated for its catalytic activity for C-C bond-formation reactions by examining the coupling reaction of 3-iodoanisole with phenylacetylene in the Sonogashira reaction. In addition, 3-methoxybiphenyls were obtained with good to excellent yields by Suzuki coupling reactions of 3-iodoanisole with phenylboronic acids or phenylborates salts in the presence of this complex.

Abstract

A palladium complex with an aminophosphine ligand has been prepared and investigated as a catalyst precursor in Suzuki coupling reactions in toluene. Nanoparticles composed of elemental palladium have been isolated from the reaction media and analyzed using transmission electroscopic microscope (TEM), which shows the essential catalysts palladium nanoparticles to have a size of ca. 3.0 nm.

Pure Appl. Chem., Vol. 72, No. 9, pp. 1655–1658, 2000. © 2000 IUPAC 1655 Hypervalent siloxane derivatives. An alternative to Stille and Suzuki couplings* Philip DeShong†, Christopher J. Handy, and Molly E. Mowery Department of Chemistry and Biochemistry, University of Maryland at College Park, College Park, MD 20742 USA Abstract: Siloxane methodology is extended to couplings with iodo- and bromoanilines, hin- dered arylbromides, and substituted siloxanes as substrates. Additionally, initial studies with 5-bromoindole and other heteroaromatics suggest that the

Combined Suzuki Coupling – Wittig Olefination Reaction in Aqueous Medium Kyoko Yamamotoa, Masataka Watanabea, Kyoko Idetab, Shuntaro Matakab, and Thies Thiemannb a Interdisciplinary Graduate School of Engineering Sciences and b Institute of Materials Chemistry and Engineering, Kyushu University, 6-1, Kasuga-koh-en, Kasuga-shi, 816-8580, Japan Reprint requests to Dr. T. Thiemann. E-mail: thies@cm.kyushu-u.ac.jp. Fax: (0081) +(0)92-583-7894 Z. Naturforsch. 60b, 1299 – 1307 (2005); received August 25, 2005 Bromoarene carbaldehydes and bromoheteroarene carbaldehydes

Abstract

The Heck coupling of halobenzenes with various alkenes and the Suzuki cross coupling of halobenzenes with phenylboronic acid were successfully performed in glycerol as the reaction solvent using homogeneous and heterogeneous palladium catalysts. Glycerol is a renewable and recyclable green solvent that is able to dissolve organic substrates, inorganic bases, and palladium complexes, and that allows easy isolation of the reaction product by simple extraction with glycerol-immiscible solvents such as diethyl ether, hexane, and dichloromethane.

Abstract

In the search of new materials for developing clean catalytic organic reactions, our team engineered graphene based palladium (Pd) nanocomposites and tested them as catalysts for ionic liquid mediated Suzuki cross coupling reaction. The effects of various reaction parameters, such as solvent, base, time and temperature, were investigated for the Suzuki reaction. The optimized protocol was applied to a wide range of substituted aryl/hetroaryl halides along with various aryl boronic acids and afforded the corresponding reaction products in good to excellent yield. The proposed Pd/reduced graphene oxide (rGO) catalyzed Suzuki reaction protocol was also exploited for the synthesis of unique indazole derivatives. The developed catalytic system circumvents the use of phosphine ligands, with an added advantage of easy Pd catalyst recovery up to eight times.

Polymers, 71A D. Mangeron Blvd., 700050, Iasi, Romania; tel: 040-232-21415; fax: 040-232- 271311; e-mail: vivanoiu@mail.dntis.ro 3“Petru Poni’’ Institute of Macromolecular Chemistry, Department of Electroactive Polymers, 41A Gr. Ghica Voda Alley, 700487, Iasi, Romania; tel: 040-232-217454; fax: 040-232-211299; e-mail: grim@icmpp.ro (Received: 16 February, 2009; published: 09 April, 2011) Abstract: Two novel polyazines were successfully synthesized via palladium- catalyzed Suzuki coupling method of N,N'-bis(5-bromothiophene)-2-aldehyd azine with 2

dicarbazolyltriphenylethylene-substituted fluorene derivatives were designed and synthesized in high yields via the classical Wittig-Horner and Suzuki coupling routes. To improve the solubility, linear alkyl chains were introduced into the molecular structure. This feature facilitates the deposition of high-quality films using an economical and simple solution process. The photophysical, thermal, AIEE, and electrochemical properties were evaluated. These molecules are potential materials for blue-light emitters in OLEDs. Results and discussion Synthesis The synthetic strategy is shown in