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Oxidation reactions benzyl/allyl halide preparation

The development of the Grignard-type addition to carbonyl compounds mediated by transition metals would be of interest as the compatibility with a variety of functionality would be expected under the reaction conditions employed. One example has been reported on the addition of allyl halides to aldehydes in the presence of cobalt or nickel metal however, yields were low (up to 22%). Benzylic nickel halides prepared in situ by the oxidative addition of benzyl halides to metallic nickel were found to add to benzil and give the corresponding 3-hydroxyketones in high yields(46). The reaction appears to be quite general and will tolerate a wide range of functionality. [Pg.233]

We reported that smooth oxidative addition of organic halides such as aryl, benzyl, and allyl halides to metallic nickel proceeded to afford organonickel halides under mild conditions, which yielded homocoupled products [11, 41] or ketones by the reaction with acid chlorides [42] or alkyl oxalyl chlorides [43]. We describe here a new method for the preparation of 3-aryl-2-hydroxy-l-propanones (4) in good yield by the Grignard-type addition of benzyl halides to 1,2-diketones mediated by metallic nickel under neutral conditions [44]. [Pg.262]

Allyl halides are probably the most common allylic reagents used. Palladium complexes with not only simple 77 -allylic moieties, but also cyclic derivatives, t/ -benzyls, 77 -allylic complexes derived from morphine alkaloids, and trialkyltin-subtituted T/ -allyls have been synthesized by oxidative addition of appropriate halides. Allyl carboxylates, especially acetates, are also common. When combined with other fimctionalities in the substrate, they lead to functionalized T/ -allylic Pd complexes. Examples of ester-substituted T/ -allyls obtained by reaction of the corresponding allylic trifluoroacetates 88 have been reported. Palladium complexes that bear an 7 -allyl with a pendant 2-pySiMc2-, where the py group coordinates to Pd, have been prepared from the corresponding allylic acetates 89. Allyl carbonates are also commonly used both in the stoichiometric preparation of -allylic complexes and in catalytic reactions that proceed through Pd -allylic intermediates. ... [Pg.366]

Alkyl halides (particularly bromides) undergo oxidative addition with activated copper powder, prepared from Cu(I) salts with lithium naphthalenide, to give alkylcopper species10. The alkyl halides may be functionalized with ester, nitrile and chloro functions ketone and epoxide functions may also be tolerated in some cases11. The resulting alkylcopper species have been shown to react efficiently with acid chlorides, enones (conjugate addition) and (less efficiently) with primary alkyl iodides and allylic and benzylic bromides (equations 5 and 6). If a suitable ring size can be made, intramolecular reactions with epoxides and ketones are realized. [Pg.1278]


See other pages where Oxidation reactions benzyl/allyl halide preparation is mentioned: [Pg.183]    [Pg.211]    [Pg.211]    [Pg.44]    [Pg.393]    [Pg.228]    [Pg.10]    [Pg.209]    [Pg.392]    [Pg.211]    [Pg.445]    [Pg.445]    [Pg.106]    [Pg.292]    [Pg.372]    [Pg.343]    [Pg.445]    [Pg.285]   
See also in sourсe #XX -- [ Pg.212 ]




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Allyl halides

Allyl halides reactions

Allyl oxide

Allyl preparation

Allyl-benzyl

Allylic halides

Allylic oxidation

Benzyl halides

Benzyl halides oxidation

Benzyl halides, reaction

Benzyl oxidation

Benzyl oxide

Benzyl preparation

Benzylation reactions

Benzyllic halides

Halide oxidation

Halides allylation

Halides oxides

Halides preparation

Oxidation benzylic

Oxidation benzylic halides

Oxidation preparation

Oxidizer preparation

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