Synthesis Of Symmetrical Biaryls Research Articles

Synthesis of Symmetrical Biaryls by Copper‐Catalysed Homocoupling of Aryltriazenes in Guanidinium Ionic Liquid

AbstractAn efficient, facile and practical protocol to synthesize various biaryl analogues by the homocoupling of aryl triazenes promoted by guanidinium ionic liquids via copper catalysis has been demonstrated. The three different guanidinium ILs has been employed as solvent/promoter. Several moderate to strong electron‐withdrawing groups and electron‐donating groups are well tolerated by this protocol. The predictive mechanism demonstrating the Cu‐catalytic cycle and role of GIL as promoter. This methodology provides the corresponding products in good yields under moderate reaction conditions with potential for recycling and reuse of the GIL solvent.

Ullmann homocoupling of aryl iodides catalyzed by gold nanoparticles stabilized on magnetic mesoporous silica

We demonstrated a convenient new procedure of the Ullmann homocoupling reaction for the synthesis of symmetrical biaryls via homocoupling of aryl iodides over a recyclable gold catalyst comprising Au nanoparticles supported on functional magnetic mesoporous silica (α-Fe2O3)-MCM-41-HS-Au. The catalyst was easily separated by an external magnet, and the recovered catalyst was reused in six successive reaction cycles without any significant loss of activity. So, using this catalyst is affordable. Also, the reaction time is much shorter than a few previously reported work.

Synthesis, characterization and crystal structure of Cu(II) complex of trans-cyclohexane-1,2-diamine: Application in synthesis of symmetrical biaryls

A new Cu(II) complex [Cu(cyhxn)2(H2O)2][OTf]2 was synthesised by the reaction of ligand cyhxn (cyhxn = trans-cyclohexane-1,2-diamine) with Cu(OTf)2 in methanol at room temperature. The complex was fully characterized by elemental analysis (CHN), FT-IR, UV–Vis and EPR spectroscopic techniques. The structure of the complex was confirmed by single crystal X-ray diffraction study. The EPR spectrum is isotropic type having giso = 2.078, which indicates a distorted octahedral geometry of the complex. The complex was found to be an active homogeneous catalyst for the homocoupling reactions of arylboronic acid to obtain symmetrical biaryls at room temperature in methanol without the use of any additives such as a base and or an oxidant.

Correction: Green synthesis of stable Cu(0) nanoparticles onto reduced graphene oxide nanosheets: a reusable catalyst for the synthesis of symmetrical biaryls from arylboronic acids under base-free conditions

Correction: Green synthesis of stable Cu(0) nanoparticles onto reduced graphene oxide nanosheets: a reusable catalyst for the synthesis of symmetrical biaryls from arylboronic acids under base-free conditions

Pd(OAc)2 catalyzed homocoupling of arenediazonium salts in ionic liquids: synthesis of symmetrical biaryls

A facile, high yielding, and simple method for the synthesis of a library of symmetrical biaryls by homocoupling of arenediazonium salts is reported, employing catalytic amounts of Pd(OAc)2 and the readily available imidazolium ionic liquids (ILs), without oxidants, ligands, additives, or volatile solvents. Simple product isolation and recycling/reuse of the IL represent additional advantages of this method.

Correction: Green synthesis of stable Cu(0) nanoparticles onto reduced graphene oxide nanosheets: a reusable catalyst for the synthesis of symmetrical biaryls from arylboronic acids under base-free conditions

Correction for ‘Green synthesis of stable Cu(0) nanoparticles onto reduced graphene oxide nanosheets: a reusable catalyst for the synthesis of symmetrical biaryls from arylboronic acids under base-free conditions’ by Najrul Hussain et al., Catal. Sci. Technol., 2015, DOI: 10.1039/c4cy01229a

AgF-Mediated Homocoupling Reaction of Trialkoxy Aryl Silanes

In this article, we present the direct homocoupling reaction of trialkoxy aryl silanes mediated by AgF in moderate to excellent yields in very mild conditions. It is an important complement for the synthesis of symmetrical biaryls by using homocoupling of trialkoxy silanes. In this reaction, no other catalyst such as Pd or Cu was necessary. Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for full experimental and spectral details.

One‐Step Synthesis of Biaryls under Mild Conditions

AbstractA one‐step synthesis of symmetrical biaryls was developed and uses a nickel(III) complex containing a Schiff base and dithiolate ligands as a catalyst for the homocoupling of in situ generated Grignard reagents. The coupling reaction was performed at room temperature with molecular oxygen as the oxidant, which renders the reaction energy‐efficient and environmentally friendly. The catalytic methodology is compatible with diverse functionalities, including chlorido, nitro, nitrile, and heteroatoms, and provides biaryls in appreciable yields.

ChemInform Abstract: Palladium‐Catalyzed Synthesis of Symmetrical Biaryls under Microwave Irradiation and Conventional Heating.

AbstractThe palladium‐catalyzed synthesis of symmetrical biaryls is described.

Palladium-Catalyzed Synthesis of Symmetrical Biaryls Under Microwave Irradiation and Conventional Heating

The activity of the [Pd{C6H4(CH2N(CH2Ph)2)}(µ-Br)]2 complex was investigated in the synthesis of symmetrical biaryls under both conventional and microwave irradiation conditions, and their results were compared. This complex is efficient, stable, and not sensitive to air or moisture and is a catalyst for the homo-coupling reaction of aryl iodides, bromides, and even chlorides. The products were produced in excellent yields in short reaction times using a catalytic amount of [Pd{C6H4(CH2N(CH2Ph)2)(µ-Br)]2 complex in N-methylpyrolidine (NMP) at 130 °C. In comparison to conventional heating conditions, the reactions under microwave irradiation gave better yields in shorter reaction times.

ChemInform Abstract: Ultrasound‐Assisted Synthesis of Symmetrical Biaryls by Palladium‐Catalyzed Detelluration of 1,2‐Diarylditellanes.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Ultrasound-Assisted Synthesis of Symmetrical Biaryls by Palladium-Catalyzed Homocoupling of Aryl n-Butyl Tellurides

An ultrasound-assisted synthesis of symmetrical biaryls withelectron-withdrawing or -donating substituents is described andillustrated by palladium-catalyzed homocoupling reaction of aryltellurides. This procedure offers easy access to biaryls in short reactiontime, and the products are achieved in good to excellent yields.

Copper(I)-catalysed homo-coupling of aryldiazonium salts: synthesis of symmetrical biaryls

Copper(I) triflate acts as an efficient stoichiometric reagent for the homo-coupling of aryldiazonium salts bearing electron-withdrawing group(s), to yield symmetrical biaryls in acetonitrile under mild reaction conditions. Aryldiazonium salts bearing electron-donating groups undergo the reaction by using catalytic amounts of a copper complex prepared in situ from copper(II) triflate and 2,2′-bipyridine with metallic copper as an ultimate reductant.

A New Protocol for the One‐Pot Synthesis of Symmetrical Biaryls.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Role of Copper Species in the Oxidative Dimerization of Arylboronic Acids: Synthesis of Symmetrical Biaryls.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Role of copper species in the oxidative dimerization of arylboronic acids: synthesis of symmetrical biaryls.

Certain Cu(I) and Cu(II) salts are able to mediate the dimerization of arylboronic acids in DMF. They provide the corresponding symmetrical biaryls in moderate to very good yields. It is possible to run the reaction catalytically under an oxygen atmosphere without a significant loss of yields.