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Reagent-directing group

A way to overcome such an intrinsic limitation may provide a specifically introduced reagent-directing group into an organic substrate (see Scheme 1). [Pg.68]

Such an approach necessitates two additional synthetic operations introduction as well as removal of the reagent-directing group. However, such a disadvantage at first sight should be acceptable if one could solve a selectivity problem for a synthetically valuable reaction which is otherwise not susceptible to stereocontrol. In this context transition metal catalyzed addition reactions have gained importance as a consequence of their intrinsic atom economy and efficiency which may be beneficial for enviromental and economic grounds [2],... [Pg.69]

I Controlling Stereoselectivity with the Aid of a Reagent-Directing Group... [Pg.72]

Reagent-Directing Group Controls selectivity of reaction i-iii... [Pg.73]

A Via reaction 1 and reagent a introduced modification Scheme 9. Multiple use of a reagent-directing group - towards an RDG-controlled organic synthesis. [Pg.73]

Scheme 10. Working hypothesis for the o-DPPB group to act as an organometallic reagent directing group for the conjugate addition of Gilman cuprates to acyclic enoates. Scheme 10. Working hypothesis for the o-DPPB group to act as an organometallic reagent directing group for the conjugate addition of Gilman cuprates to acyclic enoates.
Breit, B. Controlling Stereoselectivity with the Aid of a Reagent-Directing Group. Hydroformylation, Cuprate Addition, and Domino Reaction Sequences, Chem. Eur. J. 2000,1519-1524. [Pg.5]

Sulfinyl and sulfonyl groups were involved in early studies of the directive effects of substituents in nitration and other reactions with electrophilic reagents. Thus Twist and Smiles (in 1925) showed that nitration of phenyl methyl sulfone gave exclusively 3-nitrophenyl methyl sulfone. The results of bromination and sulfonation were analogous, so S02Me was established, like NO2, as a mefa-directing group. [Pg.532]

It has been proposed that a directed cuprate addition with a carbamate or a carbonate serving as a reagent-directing functional group may account for the stereochemical outcome of these reactions (see models 115 and 116 in Scheme 6.25) [39, 48]. [Pg.201]

Scheme 6.26. Construction of polyketide building blocks by sequential directed stereoselective hydroformylation and directed cuprate addition with the aid of the reagent-directing o-DPPB group. (o-DPPB = ortho-diphenylbenzoylphosphanyl, DME = dimethoxyethane)... Scheme 6.26. Construction of polyketide building blocks by sequential directed stereoselective hydroformylation and directed cuprate addition with the aid of the reagent-directing o-DPPB group. (o-DPPB = ortho-diphenylbenzoylphosphanyl, DME = dimethoxyethane)...
See other pages where Reagent-directing group is mentioned: [Pg.156]    [Pg.201]    [Pg.201]    [Pg.73]    [Pg.79]    [Pg.516]    [Pg.522]    [Pg.408]    [Pg.201]    [Pg.277]    [Pg.113]    [Pg.156]    [Pg.201]    [Pg.201]    [Pg.73]    [Pg.79]    [Pg.516]    [Pg.522]    [Pg.408]    [Pg.201]    [Pg.277]    [Pg.113]    [Pg.105]    [Pg.119]    [Pg.146]    [Pg.218]    [Pg.218]    [Pg.532]    [Pg.940]    [Pg.705]    [Pg.49]    [Pg.940]    [Pg.223]    [Pg.627]    [Pg.627]    [Pg.695]    [Pg.268]    [Pg.164]    [Pg.30]    [Pg.271]    [Pg.128]    [Pg.141]    [Pg.211]    [Pg.218]    [Pg.218]   
See also in sourсe #XX -- [ Pg.201 ]

See also in sourсe #XX -- [ Pg.201 ]

See also in sourсe #XX -- [ Pg.68 ]

See also in sourсe #XX -- [ Pg.201 ]



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