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Aldehydes ozone adducts

The yield data in Figures 3 and 4 can be rationalized on similar grounds. In the cis case the initial olefin-ozone adduct can be diverted to 3-heptene ozonide by butyraldehyde, and by doing so can eliminate a precursor to 3-hexene ozonide. This process continues to operate throughout a wide range of aldehyde concentrations with the total ozonide... [Pg.43]

The reagent was used to obtain (R)-( + )-frontalin (5) from the aldehyde 2, available in two steps from (3R)-( —)-linalool. The adduct 3 from reaction of 2 with 1 was converted to the diol 4 by ozonation and reduction. Treatment of 4 with BF, etherate effects conversion to the methyl ketone and then cycli/ation to 5. [Pg.69]

The trimethylsilylated ylides (1), easily generated from trimethyl chlorosilane and ylides, react with aldehydes 2 to form vi-nylsilanes 3 (2,3). The vinylphosphonium silanolates 4 are also formed. Compounds 3 are versatile reagents for further reactions (4). The ylide J (with R1 =H) reacts with aldehydes 2 to give the dienes j). The oxidation of with the adduct 6, from triphenyl-phosphite and ozone, gives access to a generaT synthesis of acyl-silanes (trimethylsilylketones) (2). The silylated ylides react to form phosphonium salts 7 with halogen compounds. The salts 7.can be desilylated by fluorine ions. The disubstituted ylides JO Tormed can be converted in statu nascendi with aldehydes V[ into the tris-substituted olefin J2 (2,3). In the case of R3-I, vinyl... [Pg.25]

A-Phenylaziridines may be cleaved to the A-unsubstituted aziridines in good yield with ozone <78TL3ii9). The stable hemiaminal adducts of aziridines with aldehydes may react with amines to give aminals (A-(l-aminoalkyl)aziridines) [Pg.37]

The resin-bound chiral auxiliary 84 was allowed to react with different vinyllith-ium reagents. The resulting alcohols 85 were treated with n-BuLi, methyl chloro-formate and different cuprate reagents. Finally, the a-alkylated adducts 86 were liberated from the polymer with ozone followed by one of three different workup conditions to provide a primary alcohol, an aldehyde or a carboxylic acid (Scheme 12.32). [Pg.352]

In contrast to the reaction with OH, however, the intermediate appears to revert mainly to the original reactants, whereas the forward reaction to produce S03 is slow (Calvert and Stockwell, 1984). The direct, thermal reaction of S02 with ozone also is negligibly slow. Cox and Penkett (1972) demonstrated that S02 is nevertheless converted to H2S04 aerosol at an appreciable rate when S02 is added to an ozone-alkene mixture. This suggests that an intermediate of the ozone-alkene reaction is responsible for the oxidation of S02 under these conditions. The intermediate might be either the initial adduct between ozone and the alkene or the intermediate formed from it by the split-off of an aldehyde, so that the reactions oxidizing S02 are... [Pg.319]

In another approach, lithiated allene 7.4.16 was coupled with aldehyde 7.4.17 to give adduct 7.4.18, which could be ozonized to give side chain methyl ester in 28% overall yield (273),... [Pg.120]

The results of a recent investigational of model systems provide compelling evidence that stabilized atomic oxygen is present in Compound I and Compound II of horseradish peroxidase and the reactive form of cytochrome P-450. Thus, the combination of tetrakis(2,6-dichlorophenyl)-porphinato iron(III) perchlorate (1, Scheme 1) with pentafluoro-iodoso-benzene, m-chloroperbenzoic acid, or ozone in acetonitrile at -35 C yields a green porphyrin-oxene adduct (2). This species, which has been characterized by spectroscopic, magnetic and electrochemical methods, cleanly and stereospecifically epoxidizes olefins (>99% exo-norbornene-oxide), oxidizes alcohols to aldehydes, oxidatively cleaves diols, and demethylates dimethyl aniline (Scheme 1). [Pg.140]


See other pages where Aldehydes ozone adducts is mentioned: [Pg.734]    [Pg.1440]    [Pg.734]    [Pg.42]    [Pg.43]    [Pg.44]    [Pg.168]    [Pg.84]    [Pg.1485]    [Pg.181]    [Pg.98]    [Pg.270]    [Pg.44]    [Pg.115]    [Pg.427]    [Pg.37]    [Pg.44]    [Pg.223]    [Pg.631]   
See also in sourсe #XX -- [ Pg.734 ]




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Aldehydes ozonations

Ozone adducts

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