Metal-Free Direct Arylations of Indoles and Pyrroles with Diaryliodonium Salts

Direct arylations of indoles and pyrroles with differently substituted diaryliodonium salts were shown to efficiently proceed in the absence of metal catalysts.

DOI: 10.1021/ol200601e

Palladium-Catalyzed C–H Perfluoroalkylation of Arenes

A new Pd-catalyzed reaction for the coupling between perfluoroalkyl iodides (R_FI) and simple aromatic substrates is described. The perfluoroalkylated arene products are obtained in good to excellent yields in the presence of a phosphine-ligated Pd catalyst and Cs₂CO₃ as a base. The development, optimization, scope, and preliminary mechanistic studies of these transformations are reported.

http://pubs.acs.org/doi/abs/10.1021/ol200628n

PdCl2-catalyzed efficient allylation and benzylation of heteroarenes under ligand, base/acid, and additive-free conditions

Abstract

The Author present a PdCl₂-catalyzed protocol for highly efficient allylation and benzylation of a rich variety of N-, O-, and S-containing heteroarenes under base/acid, additive, and ligand-free conditions. The method represents the very few examples for simple, universally applicable, clean, and atom-efficient functionalization of heteroarenes.

DOI: 10.1039/C1CC10953G

Nickel-Catalyzed Intramolecular Nucleophilic Addition of Aryl or Vinyl Chlorides to α-Ketoamides Through CCl Bond Activation

Nickeleophilic addition! The first example of a nickel-catalyzed direct intramolecular nucleophilic addition of aryl or vinyl chlorides to α-ketoamides through CCl bond activation is reported, which takes place under mild reaction conditions (see scheme).

DOI: 10.1002/chem.201100256

Regioselective Synthesis of Indenols by Rhodium-Catalyzed CH Activation and Carbocyclization of Aryl Ketones and Alkynes

Ketones and alkynes join together: The catalytic title reaction proceeds rapidly at 120 °C and requires only 1 hour for completion (see scheme). The reaction mechanism likely involves chelation-assisted ortho CH activation, insertion of the alkyne moiety, carbocyclization, and protonation. Cp*=pentamethylcyclopentadienyl.

DOI: 10.1002/anie.201100229

Base-Mediated Direct Arylation of Pyrrole Derivatives

Abstract

It appears that transition metal catalysts are not necessary to perform the direct arylation of electron-rich heterocycles with aryl iodides and bromides. Lithium tert-butoxide in DMF promotes this reaction for a variety of N-alkyl- and N-arylpyrroles as well as for benzofuran and some other electron-rich aromatic compounds and provides the desired products in moderate to high yields. In contrast to all previous reports on the Pd-catalyzed direct arylation of indolizine, the reaction mediated by lithium tert-butoxide proceeds selectively at position 5.

DOI: 10.1002/adsc.201000723

Mizoroki–Heck-Type Reaction Mediated by Potassium tert-Butoxide

In the absence of transition-metal catalysts, a Mizoroki–Heck-type reaction proceeded to give stilbene derivatives in a simple manner using an aryl halide, a styrene derivative, KOtBu, EtOH, and DMF (see scheme; DMF=N,N-dimethylformamide).

DOI: 10.1002/anie.201008220

2-Pyridyl Sulfoxide: A Versatile and Removable Directing Group for the PdII-Catalyzed Direct CH Olefination of Arenes

Abstract:

Removable and versatile: The 2-pyridylsulfinyl group has proved to be an efficient directing group in the Pd^II-catalyzed aryl ortho CH olefination. This catalyst system enables the sequential double olefination to give asymmetrically di-ortho-functionalized arenes. The sulfinyl directing group can be easily cleaved, providing access to 1,3-disubstituted arenes, or transformed into a thiol group.


DOI: 10.1002/chem.201003633

Controlling Site Selectivity in Pd-Catalyzed Oxidative Cross-Coupling Reactions

This paper presents a detailed investigation of the factors controlling site selectivity in the Pd-mediated oxidative coupling of 1,3-disubstituted and 1,2,3-trisubstituted arenes (aryl−H) with cyclometalating substrates (LC−H). The influence of both the concentration and the steric/electronic properties of the quinone promoter are studied in detail. In addition, the effect of steric/electronic modulation of the carboxylate ligand is discussed. Finally, we demonstrate that substitution of the carboxylate for a carbonate X-type ligand leads to a complete reversal in site selectivity for many arene substrates. The origins of these trends in site selectivity are discussed in the context of the mechanism of Pd-catalyzed oxidative cross-coupling.


http://pubs.acs.org/doi/abs/10.1021/ja1097918

Base-Mediated Intermolecular sp2 C−H Bond Arylation via Benzyne Intermediates

Abstract:

A transition-metal-free method for arylation of heterocycle and arene carbon−hydrogen bonds by aryl chlorides and fluorides has been developed. The reactions proceed via aryne intermediates and are highly regioselective with respect to the C−H bond coupling component.

Rh(NHC)-Catalyzed Direct and Selective Arylation of Quinolines at the 8-Position

Abstract:

A new catalytic protocol for the regioselective direct arylation of quinoline derivatives at the 8-position has been developed. The reaction is catalyzed by a Rh(NHC) system, and the choice of the NHC ligand was most important for achieving high reactivity and selectivity.

http://pubs.acs.org/doi/abs/10.1021/ja111670s

Iridium-catalysed direct C–C coupling of methanol and allenes

J Moran et al, Nat Chem, 2011, DOI: 10.1038/nchem.1001

Complexation between Pentiptycene Derived Bis(crown ether)s and CBPQT4+ Salt: Ion-Controlled Switchable Processes and Changeable Role of the CBPQT4+ in Host−Guest Systems

http://pubs.acs.org/doi/abs/10.1021/jo102288r

Annulation of Benzamides with [60]Fullerene through Palladium(II)-Catalyzed C−H Bond Activation

http://pubs.acs.org/doi/abs/10.1021/jo102107k

Exploration of New C−O Electrophiles in Cross-Coupling Reactions

 

DOI: 10.1021/ar100082d