N-Heterocyclic Carbenes in Late Transition Metal Catalysis

Metal catalysts for the vinyl/addition polymerization of norbornene

Mononuclear palladium-allyl complexes bearing one N-heterocyclic carbene (NHC) ligand have been synthesized. These complexes offer a straightforward entryway into a number of catalytic cycles by simple action of a base.

Activation and reactivity of (NHC)Pd(allyl)Cl (NHC = N-heterocyclic carbene) complexes

Stereochemical and structural characteristics of single- and double-site Pd(II)–N-heterocyclic carbene complexes: Promising catalysts in organic syntheses ranging from CC coupling to olefin polymerizations

The bigger the better: The new well-defined [Pd(IPr*)(cin)Cl] pre-catalyst is described. This complex proves to be highly active in the Suzuki-Miyaura cross-coupling for the synthesis of tetra-ortho-substituted biaryls under mild conditions. IPr* is reported as the largest N-heterocyclic carbene (NHC) to date for [Pd(NHC)(cin)Cl] complexes, explaining the high reactivity observed for this complex in this challenging transformation.

[Pd(IPr*)(cinnamyl)Cl] : an efficient pre-catalyst for the preparation of tetra-ortho-substituted biaryls by Suzuki-Miyaura cross-coupling

An in situ generated cationic allylpalladium complex bearing N-heterocy- clic carbene (NHC) ligands, derived from the reaction of ((g 3 -C3H5)Pd(NHC)Cl) with AgX (X ¼ BF4 or SbF6), is an active catalyst for the addition polymerization of norbor- nene and norbornene derivatives (5-norbornene-2-carboxylic acid methyl ester (b )a nd 5-norbornene-2-carboxylic acid n-butyl ester (c)) with an ester group containing a large portion of endo-isomers. The catalytic activities, polymer yields, molecular weights, and molecular weight distributions of polynorbornenes were investigated under various reaction conditions: the catalytic activity was highly dependent on the counteranion, the reaction solvent, and the reaction temperature. For b, as the portion of an endo-iso- mer increased, the activity of 13(SbF � ) was much higher than those of 14 and 15 ,a nd for c (exo/endo ¼ 95:5), the maximum turn over number (TON) was observed with 15(SbF � ). V C 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3042-3052, 2007

Polymerization of carboxylic ester functionalized norbornenes catalyzed by (η3‐allyl)palladium complexes bearing N‐heterocyclic carbene ligands

Polymerization of 5-norbornene-2-methyl acetate catalyzed by air-stable cationic (η3-substituted allyl) palladium complexes of N-heterocyclic carbene

Cationic NHC–Pd (NHC = N-heterocyclic carbene) complex-catalyzed cycloisomerization of dienes

Nickel oxide nanoparticles, readily available and easy to handle, were found to be an effective catalyst in the catalytic activation of C-Cl bonds in chloroalkanes. Coupling reactions of chloroalkanes and tertiary amines in the presence of the nickel oxide nanoparticle catalyst gave moderate to high yields of quaternary ammonium salts depending upon the amines.

Il Gu Jung

Papers

Polymerization of carboxylic ester functionalized norbornenes catalyzed by (η3‐allyl)palladium complexes bearing N‐heterocyclic carbene ligands

Polymerization of 5-norbornene-2-methyl acetate catalyzed by air-stable cationic (η3-substituted allyl) palladium complexes of N-heterocyclic carbene

Cationic NHC–Pd (NHC = N-heterocyclic carbene) complex-catalyzed cycloisomerization of dienes

Activation of CCl Bonds in Chloroalkanes by Nickel Oxide Nanoparticles: Formation of Tetrasubstituted Ammonium Salts from Tertiary Amines

Palladium‐catalyzed Aerobic Oxidation Reaction of 1‐Heptanol in Water using Water‐soluble N‐Heterocyclic Carbene Ligands