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Derivatives stereospecific

The vinylogous elimination to give alkenylcyclopropanes may also be effected via rt-allyl palladium complexes34,35. The palladium(0)-catalyzed substitution of allylic esters with stabilized carbon nucleophiles via 7i-allyl palladium derivatives stereospecifically proceeds with net retention (double inversion) of configuration. Thus, the chirality of an allylic substrate is transferred to resultant alkenylcyclopropanes in the intramolecular S J/ reaction via 7i-allyl palladiums (equation 21)36,3. ... [Pg.268]

The lactone 2 is transformed via several steps into the 7-azido-2-isooxaphem 3 and the 7-azido-2-isocephem 4. Reduction of the azide groups, acylation and removal of the protecting groups gives the corresponding cephalosporin derivatives stereospecifically. [Pg.643]

Polymer-supported peracids are also used effectively for the epoxidation of di-and trisubstituted olefins. The ratio of the stereoisomers is similar to that for the products of the reaction of the monomer with aromatic peracids. MCPBA epoxidation of homoallyl phosphonates has led to the preparation of 3,4-epoxyalkane phosphonates 39 in addition to the 1,2- and 2,3-epoxy derivatives.Stereospecific peracid oxidation is one of the preparative methods employed in the synthesis of the structurally varied cyclic polyoxirane isomers, which are of interest from a biological aspect. ... [Pg.24]

Bromohydrins from ethylene derivatives Stereospecific Marknownikoff addition... [Pg.406]

Aliphatic nitro compounds from 1,1-nitroethylene derivatives Stereospecific hydrogenation of carbon-carbon double bonds... [Pg.34]

Borane-hydrogen peroxide sodium hydroxide Alcohols from ethylene derivatives Stereospecific Brown hydration... [Pg.56]

Hydrocarbons from acoxy compounds frans-Ethylene derivatives—Stereospecific synthesis... [Pg.256]

Terminal acetylene from ethylene derivs. Stereospecific synthesis with addition of 2 C-atoms... [Pg.173]

Silver fluoride 1,2-Fluoroiodides from ethylene derivs. Stereospecific addition... [Pg.118]

Carboxylic acids from ethylene derivatives Stereospecific synthesis with addition of 1 C-atom... [Pg.443]

Section 10 12 Conjugate addition of an alkene (the dienophile) to a conjugated diene gives a cyclohexene derivative in a process called the Diels-Alder reaction It is concerted and stereospecific substituents that are cis to each other on the dienophile remain cis m the product... [Pg.418]

See other pages where Derivatives stereospecific is mentioned: [Pg.606]    [Pg.162]    [Pg.84]    [Pg.458]    [Pg.327]    [Pg.208]    [Pg.415]    [Pg.61]    [Pg.99]    [Pg.419]    [Pg.69]    [Pg.279]    [Pg.606]    [Pg.162]    [Pg.84]    [Pg.458]    [Pg.327]    [Pg.208]    [Pg.415]    [Pg.61]    [Pg.99]    [Pg.419]    [Pg.69]    [Pg.279]    [Pg.373]    [Pg.210]    [Pg.537]    [Pg.234]    [Pg.277]    [Pg.310]    [Pg.310]    [Pg.157]    [Pg.4]    [Pg.283]    [Pg.33]    [Pg.36]    [Pg.64]    [Pg.71]    [Pg.75]    [Pg.75]    [Pg.81]    [Pg.82]    [Pg.84]    [Pg.86]    [Pg.90]    [Pg.151]    [Pg.153]    [Pg.156]    [Pg.161]    [Pg.177]   
See also in sourсe #XX -- [ Pg.22 , Pg.143 ]



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