Stable, CH2Cl2-soluble mixed dodecanethiol/(amidoferrocenyl)alkanethiol (AFAT) gold colloids were synthesized by ligand substitution reactions from Brust's dodecanethiol and the AFAT ligands to study recognition titration of oxoanions. Gold obtained with various chain lengths (C11 C6 chains) different proportions in colloids. Modification amidoferrocenyl structure [replacement free C5H5 ferrocene ring C5Me5 (Cp*) or C5H4COCH3] has been achieved investigate stereoelectronic effects on...

Air-stable neutral and cationic palladium complexes bearing chiral phosphine-N-heterocyclic carbene ligands with planar chirality only have been prepared in moderate to good yields characterized by NMR X-ray diffraction studies. They are shown catalyze the asymmetric coupling of aryl bromides arylboronic acids enantioselectivities (up 42% ee) low catalyst loadings (0.1−0.5 mol %).

Gold colloids containing a mixture of alkylthiol and amidoferrocenylalkylthiol (AFAT) ligands are new redox sensors for H2PO4− HSO4−.

Catalytic, enantioselective, tandem carbonyl ylide formation/cycloaddition of 2-diazo-3,6-diketoester 2 with the use dirhodium tetrakiscarboxylate and tetrakisbinaphtholphosphate catalysts to give cycloadducts 3 in good yields up 90% ee is described.

Catalytic enantioselective tandem carbonyl ylide formation−intramolecular 1,3-dipolar cycloaddition reactions of 2-diazo-3,6-diketoesters show promising scope in terms asymmetric induction as the tethered alkene/alkyne dipolarophile component is varied. Cycloadditions were found to occur moderate very good yields, with a difference ee exhibited by electronically different 1, 25 and 33, 34. Values for up 90% alkene dipolarophiles 86% alkyne obtained.

Abstract Five new, bifunctional imidazolium–thioether ligands of the general formula RS(CH 2 ) n (imidazolium) + ArBr – ( = or 3, R Et t Bu, Ar 2,4,6‐trimethylphenyl 2,6‐diisopropylphenyl) have been synthesised in good overall yields by a method and used as N‐heterocyclic carbene precursors for complexation studies on various transition metals (Ni II , Pd Rh I ). Sulfur does not coordinate nickel centre, whereas two functional groups bind palladium centre to form dinuclear compound. Cationic...

Catalyzed cascade reactions that generate molecular complexity rapidly and in an enantioselective manner are attractive methods for asymmetric synthesis. In the present article, chiral rhodium catalysts shown to effect such a transformation by using range of 2-diazo-3,6-diketoesters with bicyclo[2.2.1]alkenes styrenes as reaction partners. The likely proceed formation catalyst-complexed carbonyl ylide from diazo compound, followed intermolecular cycloaddition alkene dipolarophile. It was...

Complex Ru(CO)2(PPh3)3, 1, is a suitable starting compound for the generation of N-heterocyclic carbene complexes Ru(0). Although monodentate NHCs are totally unreactive toward phosphine- or olefin-functionalized carbenes, as well their imidazolium precursors, react with 1 under chelation assistance where phosphine olefin acting directing group. Reactions 1-mesityl-3-(2-diphenylphosphinoeth-1-yl)imidazolium bromide, [HL1a]+Br−, tetrafluoroborate, [HL1a]+BF4−, and...

We describe here the first examples of planar chiral ferrocenyl phosphane–benzimidazol-2-ylidene ligands and their coordination chemistry with palladium(II). All ligand precursors, namely enantiopure phosphane–(benz)imidazolium salts, all palladium complexes have been fully characterised by 1H, 31P 13C NMR, mass spectrometry X-ray diffraction methods for seven examples. The potential these very bulky bidentate in catalysis was evaluated compared to imidazol-2-ylidene analogues. influence...

Abstract Two ferrocenylmethanols, [1′‐(diphenylthiophosphanyl)ferrocen‐1‐yl]methanol ( 3 ) and [2‐(diphenylthiophosphanyl)ferrocen‐1‐yl]methanol 6 ), have been converted in one step into the 1,1′‐ 1,2‐ferrocenediyl‐linked thiophosphane/ N ‐R‐imidazolium salts 4a , b 7a a : R = Me; 2,4,6‐Me C H 2 or Mes). This straightforward method allows linkage of an imidazolium group to ferrocene unit with nonsubstituted methylene bridge. After desulfurisation phosphane group, ligands reacted Rh I...

The oxidation of a rhodium(I) complex containing ferrocene-based heterodifunctional phosphine N-heterocyclic carbene (NHC) ligand produces stable, planar chiral rhodium(III) with an unexpected C–H activation on ferrocene. to may be accomplished by initial ferrocene ferrocenium and subsequent electron transfer from rhodium ferrocenium. Preliminary catalytic tests showed that the is active for Grignard-type arylation 4-nitrobenzaldehyde via 2-phenylpyridine.

Abstract N ‐[(1‐Phosphanylferrocen‐1′‐yl)methyl]‐ N′ ‐[(2,4,6‐trimethylphenyl)methyl]‐5,6‐di‐X‐benzimidazolium tetrafluoroborate salts (X = H, 5a and Me, 5b ), precursors of new phosphane‐benzimidazol‐2‐ylidene bifunctional ligands, related ferrocenyl 5,6‐di‐X‐benzimidazol‐2‐ylidene iodide 6a 6b monodentate benzimidazol‐2‐ylidene have been prepared for the first time. Cationic rhodium(I) complexes 7a 7b neutral 8a 8b obtained in good yields fully characterised. 10a 10b were from , comparison...

Abstract N ‐(Quinoline‐8‐yl‐aryl)benzenesulfonamides 1 – 6 were successfully synthesized by the reaction of 8‐aminoquinoline and various benzenesulfonyl chlorides. Then, half‐sandwich ruthenium complexes 7 12 prepared from reactions with [RuCl 2 (p‐cymene)] . The compounds characterized NMR FTIR spectroscopy elemental analysis, 8 9 further analyzed X‐ray diffraction. screened for their efficiency as catalysts in transfer hydrogenation acetophenone derivatives to phenylethanols presence KOH...

Asymmetric palladium catalyzed allylic amination of 5 with various amines has been studied using a new class chiral pyridine-phosphine ligands. High enantioselectivities up to 94% ee have observed benzylamine, veratrylamine or morpholine as nucleophiles.

Abstract The unusual reactivity of chelating phosphane–imidazolium salts MesImEtPPh 2 + Br – , DIPP‐ImEtPPh and BF 4 towards the low‐oxidation‐state iridium complex [Ir(COD)(μ‐Cl)] was studied. In absence a base, C–H insertion at C5 position imidazolium ring only reaction that occurred, with no normal NHC observed, leading to hydridoiridium(III) complexes. This independent nature counteranion substitution pattern aryl group. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Half-sandwich rhodium(III) and ruthenium(II) complexes bearing a new redox-active ferrocenyl NHC–thioether ligand have been prepared. The synthesis of thioether-imidazolium salts 3a 3b was carried out via intermediate 2 using an improved procedure. Rhodium(III) complex 4 5 were obtained in good yields fully characterised by NMR spectroscopy, X-ray diffraction analysis electrochemistry. Complex shows ABCD system 1H NMR, which denotes conformational rigidity due to the presence several bulky...

Dicarbonyl-stabilised diazo functionality is tolerated during alkene cross-metathesis using Grubbs' catalyst, but undergoes subsequent tandem carbonyl ylide formation-intramolecular 1,3-dipolar cycloaddition on addition of catalytic Rh2(OAc)4 in a one-pot operation.