Alcohol oxidations are typically performed with stoichiometric reagents that generate heavy-metal waste and usually run in chlorinated solvents. A water-soluble palladium(II) bathophenanthroline complex is a stable recyclable catalyst for the selective aerobic oxidation of wide range alcohols to aldehydes, ketones, carboxylic acids biphasic water-alcohol system. The use water as solvent air oxidant makes reaction interesting from both an economic environmental point view.

Over the past decade, metabolomics has developed into a major tool for studying metabolism of organisms and cells, through this approach much been learned about metabolic networks reactions to various external conditions ([Lay et al., 2006][1]). Most work

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHeterogeneous Catalysts for Liquid-Phase Oxidations: Philosophers' Stones or Trojan Horses?Roger A. Sheldon, Martin Wallau, Isabel W. C. E. Arends, and Ulf SchuchardtView Author Information Laboratory of Organic Chemistry Catalysis, Delft University Technology, Julianalaan 136, 2628 BL Delft, The Netherlands, Instituto de Química, Universidade Estadual Campinas, Caixa Postal 6154, 13083-970 Campinas-SP, Brazil Cite this: Acc. Chem. Res. 1998, 31,...

Abstract The use of nitroxyl radicals, alone or in combination with transition metals, as catalysts oxidation processes is reviewed from both a synthetic and mechanistic viewpoint. Two extremes reactivity can be distinguished: stable (persistent) dialkylnitroxyls, such the archetypal TEMPO, reactive diacylnitroxyls, derived N ‐hydroxy imides, ‐hydroxyphthalimide (NHPI). different types observed are rationalized by considering bond dissociation energies (BDEs) respective precursors,...

The combination of RuCl2(PPh3)3 and TEMPO affords an efficient catalytic system for the aerobic oxidation a variety primary secondary alcohols, giving corresponding aldehydes ketones, in >99% selectivity all cases. Ru/TEMPO displayed preference vs alcohols. Results from Hammett correlation studies (ρ = −0.58) kinetic isotope effect (kH/kD 5.1) benzyl alcohol oxidations are inconsistent with either oxoruthenium (ORu) or oxoammonium based mechanism. We postulate hydridometal mechanism,...

[CuBr2(2,2'-bipyridine)] catalyses the selective and very mild aerobic oxidation of primary alcohols to aldehydes in acetonitrile:water (2:1) presence 2,2,6,6-tetramethylpiperidinyl-1-oxy (TEMPO) a base as cocatalysts.

Preface. Foreword. 1 Introduction: Green Chemistry and Catalysis. 1.1 Introduction. 1.2. E Factors Atom Efficiency. 1.3 The Role of 1.4 Development Organic Synthesis. 1.5 Catalysis by Solid Acids Bases. 1.6 Catalytic Reduction. 1.7 Oxidation. 1.8 C-C Bond Formation. 1.9 Question Solvents: Alternative Reaction Media. 1.10 Biocatalysis. 1.11 Renewable Raw Materials White Biotechnology. 1.12 Enantioselective 1.13 Risky Reagents. 1.14 Process Integration Cascades. References. 2 Bases as...

Biocatalysis is an enabling technology adding to organic oxidation chemistry. Especially the high selectivity of enzymatic coevally operating under mild conditions and not necessitating problematic solvents makes it a very valuable tool for (green) The present state art in use enzymes microorganisms catalytic oxyfunctionalization chemistry reviewed.

When challenged by a difficult reduction reaction, chemist should always also consider biocatalysis in synthesis planning. The inherent selectivity of enzymes has been known for many decades now and the practical applicability undergone dramatic improvements rendering it true alternative to established chemocatalysis. In this contribution recent developments field enzymatic using whole cells isolated are reviewed.

Abstract Redox enzymes have tremendous potential as catalysts for preparative organic chemistry. Their usually high selectivity, paired with their catalytic efficiency under mild reaction conditions, makes them potentially very valuable tools synthesis. The number of interesting monooxygenases, dehydrogenases, reductases, oxidases, and peroxidases is steadily increasing the tailoring a given biocatalyst more becoming standard technology. However, cofactor dependency still represents major...

Abstract Zeolites are viewed by some as the “philosopher's stone” of modern chemistry. [1] They more or less indispensable in oil refining and petrochemicals manufacture where they widely applied solid acid catalysts. More recently attention has been focused on their use fine chemicals. The synthetic utility zeolites related molecular sieves (zeotypes) considerably extended incorporation redox metals into frameworks. resulting catalyze a variety selective oxidations under mild conditions...

Abstract A novel and very mild method for the oxidation of primary alcohols to aldehydes with excellent conversions has been developed. The reaction is carried out under air at room temperature catalysed using a [copper(II)‐(N ligand) n ] complex TEMPO base as co‐catalysts. In this paper, performance series N‐containing ligands, well different copper(II) salt precursors in solvents are reported. Best results obtained acetonitrile/water solvent catalyst generated situ from Cu(II) weak or...

Water-soluble complexes of palladium(II) with phenanthroline-derivatives are stable, recyclable catalysts for the selective aerobic oxidation a wide range alcohols to aldehydes, ketones, and carboxylic acids in biphasic liquid-liquid system. The active catalyst is dihydroxy-bridged palladium dimer. Kinetics reaction, ligand anion effects discussed.

Biocatalysis is propagating into practically every area of organic chemistry, amongst them radical polymerizations. A review the recent developments this dynamic and quickly evolving research presented together with a critical evaluation its potential to yield novel polymers and/or environmentally more benign synthetic procedures.

Results from Hammett correlation studies and primary kinetic isotope effects for the CuCl–TEMPO catalysed aerobic benzyl alcohol oxidations are inconsistent with an oxoammonium based mechanism. We postulate a copper-mediated dehydrogenation mechanism, in which TEMPO regenerates active Cu(II)-species. This mechanism is analogous to that observed Galactose Oxidase mimics thereof.