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Palladium catalysis olefination, oxygen oxidant

Oxidation of terminal olefins to methyl ketones by aqueous palladium chloride and oxygen is very slow, but addition of micellar sodium lauryl sulphate increases the rate of formation of 2-octanone from 1-octene twentyfold at 50 °C. There is weaker catalysis by the non-ionic surfactant Brij-35 and inhibition by cationic surfactants. " Oxidation of diosphenol (35) in basic aqueous tetradecyltrimethylammonium chloride is faster and more effective than in water, giving a higher yield of (36). Two attempts at effecting the enantioselective reduction of aromatic ketones, one in micelles of R-dodecyl-dimethyl-a-phenylethylammonium bromide and the other in sodium cho-late micelles, both give optical yields of less than 2%. Rather more success was obtained in the catalysed oxidation of L-Dopa, 3,4-dihydroxyphenyI-alanine. In the presence of the Cu complex of N-lauroyl-L-histidine in cetyl-trimethylammonium bromide micelles reaction was 1.42 (pH 6.90, 30 °C) to... [Pg.200]

In 1992 Murahashi, Hosokawa, and co-workers described the anti-Markovnikov oxidative addition of amides and carbamates to electron-deficient olefins by applying a palladium and copper cooperative catalysis under oxygen atmosphere [41]. The proposed mechanism involved a ff-bonded palladium(II) intermediate resulting from the addition of the nucleophile to the olefin, and subsequent ) -palladium hydride elimination to yield the functionalized alkene. Interestingly, both lactams and cyclic carbamates gave predominantly the corresponding E-enamide derivatives. Acyclic amides, conversely, afforded ElZ mixtures of products. The addition of a catalytic amount (5 mol%) of hexamethylphosphoric triamide (HMPA) was found notably beneficial for the reaction of 5-membered lactams and reduced the reaction time of such particular oxidative amidations (Scheme 2). [Pg.57]


See other pages where Palladium catalysis olefination, oxygen oxidant is mentioned: [Pg.176]    [Pg.244]    [Pg.1327]    [Pg.254]    [Pg.202]    [Pg.58]    [Pg.50]    [Pg.34]   
See also in sourсe #XX -- [ Pg.130 ]




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Catalysis olefins

Olefin oxide

Olefinations oxidative

Olefines, oxidation

Olefins oxygenation

Olefins, oxidation

Oxidation catalysis

Oxidation palladium

Oxidative olefin

Oxidative olefination

Oxides catalysis

Oxygen Palladium

Oxygen olefination

Palladium catalysis

Palladium catalysis olefinations

Palladium catalysis oxidation

Palladium catalysis oxygenation

Palladium olefin oxidation

Palladium oxide

Palladium oxidized

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