s, or keywords if they used Heck-type chemistry in their syntheses, because it became one of basic tools of organic preparations, a natural way to

http://aether.cmi.ua.ac.be/artikels/Artikels%20Gitte/Artikels/Reviews/Heck%20reactie%20Beletskaya%20%20Chem.%20Rev.%20003009.pdf

The heck reaction as a sharpening stone of palladium catalysis.

Catalytic dehydrogenative cross-coupling: forming carbon-carbon bonds by oxidizing two carbon-hydrogen bonds

/pdf/aryl-aryl-bond-formation-one-century-after-the-discovery-of-1jdyxlkwix.pdf

Aryl-aryl bond formation one century after the discovery of the Ullmann reaction.

The biaryl structural motif is a predominant feature in many pharmaceutically relevant and biologically active compounds. As a result, for over a century 1 organic chemists have sought to develop new and more efficient aryl -aryl bond-forming methods. Although there exist a variety of routes for the construction of aryl -aryl bonds, arguably the most common method is through the use of transition-metalmediated reactions. 2-4 While earlier reports focused on the use of stoichiometric quantities of a transition metal to carry out the desired transformation, modern methods of transitionmetal-catalyzed aryl -aryl coupling have focused on the development of high-yielding reactions achieved with excellent selectivity and high functional group tolerance under mild reaction conditions. Typically, these reactions involve either the coupling of an aryl halide or pseudohalide with an organometallic reagent (Scheme 1), or the homocoupling of two aryl halides or two organometallic reagents. Although a number of improvements have developed the former process into an industrially very useful and attractive method for the construction of aryl -aryl bonds, the need still exists for more efficient routes whereby the same outcome is accomplished, but with reduced waste and in fewer steps. In particular, the obligation to use coupling partners that are both activated is wasteful since it necessitates the installation and then subsequent disposal of stoichiometric activating agents. Furthermore, preparation of preactivated aryl substrates often requires several steps, which in itself can be a time-consuming and economically inefficient process.

http://aether.cmi.ua.ac.be/artikels/Artikels%20Gitte/Artikels/Reviews/Heck-Type-lautens.pdf

Aryl-aryl bond formation by transition-metal-catalyzed direct arylation.

N-Heterocyclic Carbenes in Late Transition Metal Catalysis

π-Acceptor molecules covalently attached on hydrophilic support were used to selectively remove neutral nitrogen heterocyclic compounds from diesel feed by a charge transfer mechanism. Functionalized hydrophilic polymers can effectively adsorb nitrogen heterocyclic compounds with a high selectivity toward sulfur heterocyclic compounds from model and real feed. The results showed that charge transfer processes coupled with an ion-exchange process to selectively remove basic nitrogen compounds are efficient enough to produce denitrogenated feed in high yield. This study was conducted to determine whether trends in hydrodesulfurization (HDS) activity with lower sulfur content were mainly the result of lower reactivity of hindered sulfur compounds or due to nitrogen species inhibition. The inhibition effects of nitrogen compounds on HDS at conditions commonly used in the hydrotreatment of gas oil feedstocks has been experimentally determined. This study suggests that the selective removal of nitrogen compound...

Novel Methodology toward Deep Desulfurization of Diesel Feed Based on the Selective Elimination of Nitrogen Compounds

To protect urban areas, new environmental regulations have been adopted to limit the sulfur level in diesel fuel. It is well established that among all sulfur-containing compounds present in gas oi...

Selective elimination of alkyldibenzothiophenes from gas oil by formation of insoluble charge-transfer complexes

Chiral cobalt-diamine complexes have been prepared and tested in catalytic reduction of β-ketoesters and ketones with molecular hydrogen or hydride transfer reduction (HTR). Modest to high conversions, but low e.e.s were obtained in the first case, whereas encouraging e.e.s (up to 58%) but low conversions were observed in the reduction of acetophenone by HTR. Synthesis of chiral nitrogen tetradentate ligands for Co, Ir and Rh are described. Furthermore, (1R,2R)-(−)-N-tosyl-1,2-ethanediamine proved to be a particularly efficient ligand for iridium in the hydride transfer reduction of acetophenone (87% conversion, 92% e.e.).

Emmanuelle Schulz

Papers

Novel Methodology toward Deep Desulfurization of Diesel Feed Based on the Selective Elimination of Nitrogen Compounds

Selective elimination of alkyldibenzothiophenes from gas oil by formation of insoluble charge-transfer complexes

Chiral nitrogen-metal complexes for the asymmetric reduction of ketones

Calcium(II)-Catalyzed Aza-Piancatelli Reaction

Chiral Amido Alkyl Rare Earth Complexes: A New Family of Asymmetric Intramolecular Hydroamination Catalysts