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Conjugate addition alkylation

Several examples of tandem conjugate addition-alkylation follow. [Pg.190]

Tandem conjugate addition-alkylation has proven to be an efficient means of introducing groups at both a- and (3-positions at enones.307 As with simple conjugate addition, organocopper reagents are particularly important in this application, and they are discussed further in Section 8.1.2.3. [Pg.190]

Scheme 8.3. Tandem Conjugate Addition-Alkylation Using Organocopper Reagents... [Pg.691]

Scheme 3.6. Diastereoselectivity in silylcuprate conjugate addition-alkylation (alkyl halides) or protonation reactions with a,/S-enoates [46],... Scheme 3.6. Diastereoselectivity in silylcuprate conjugate addition-alkylation (alkyl halides) or protonation reactions with a,/S-enoates [46],...
Tandem conjugate addition-alkylation has proven to be an efficient means of introducing both a and substituents at enones."... [Pg.45]

Prior to protonolysis, the products of conjugate addition to unsaturated carbonyl compounds are enolates and, therefore, potential nucleophiles. A useful extension of the conjugate addition method is to combine it with an alkylation step that adds a substituent at the a position.52 Several examples of this tandem conjugate addition/alkylation procedure are given in Scheme 8.2. [Pg.489]

Among the most important of these tandem conjugate addition-alkylation reactions are those of cyclopentenones. With cyclopentenone itself, the trans diastereoisomer usually results because the alkylating agent approaches from the less hindered face of the enolate. [Pg.686]

We left compound 35 as the product of a tandem conjugate addition/alkylation and promised further chemistry later in the chapter. In fact, 35 was used in another more remarkable tandem sequence involving two pericyclic reactions and the creation of a polycyclic Daphniphyllum alkaloid. The first few steps are straightforward and give diol 173 in good yield.8... [Pg.884]

Keywords Ligand, Ether, Amine, Nucleophilic addition, Organolithium, Grignard reagent, Organozinc, Copper, Phosphorus, Conjugate addition. Alkylation, Phosphine, Activated olefin, P-Substituted carbonyl compound... [Pg.1042]

Fuchs elegant approach to the morphinan skeleton utilized an intramolecular conjugate addition/alkylation sequence, in which connections C12-C13 and C9-C14 were formed as a result of one tandem process.73-74 Mitsunobu condensation between alcohol 164 (from 2-allylcyclohexene-l,3-dione in five steps and 43% overall yield) and phenol 163 (from isovanilline in 6 steps and overall yield of 40%)73c gave the ether 165, Scheme 19. TBDMS deprotection followed by an oxidation/reduction sequence set the aryl ether... [Pg.88]

Aoyl-anion equivalents - conjugate addition + alkylation... [Pg.397]

AUXILIARY ON DONOR NUCLEOPHILE - TANDEM ADDITION 7.2.1 Acyl-anion equivalents - conjugate addition + alkylation... [Pg.446]

See other pages where Conjugate addition alkylation is mentioned: [Pg.249]    [Pg.273]    [Pg.690]    [Pg.179]    [Pg.266]    [Pg.291]    [Pg.711]    [Pg.709]    [Pg.112]    [Pg.249]    [Pg.274]    [Pg.1072]    [Pg.361]    [Pg.33]    [Pg.83]    [Pg.1072]    [Pg.86]    [Pg.397]    [Pg.397]    [Pg.397]    [Pg.525]    [Pg.525]    [Pg.563]   
See also in sourсe #XX -- [ Pg.24 , Pg.25 , Pg.26 ]

See also in sourсe #XX -- [ Pg.739 ]



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Addition alkylation

Alkylative addition

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