Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Alkylation of Carbon via Enolates and Enamines

CHAPTER 1 ALKYLATION OF CARBON VIA ENOLATES AND ENAMINES 0. 0 C2H5OCCH2COC2H5 + B OHO II 1 II C2H5OC-C-COC2H5 + BH... [Pg.3]

B.iv. Nitrile Enolates. Nitrile enolates are formed by reaction of a nitrile with LDA or another suitable base. Both alkylation 30 and condensation reactions with aldehydes 3 or ketones are known. 32 in addition to alkyl halides and carbonyl derivatives, condensation can occur with another nitrile. The base-catalyzed condensation of two nitriles to give a cyano-ketone, via an intermediate cyano enolate, is known as the Thorpe reaction. 33.109e Reaction of butanenitrile with sodium ethoxide gave a nitrile enolate, which reacted with a second molecule of butanenitrile at the electrophilic cyano carbon to give 206. Hydrolysis gave an intermediate imine-nitrile (207), which is in equilibrium with the enamine form (208, sec. 9.6.A). Hydrolysis led to the final product of the Thorpe reaction, an a-cyano ketone, 209. 33 Mixed condensations are possible when LDA and kinetic conditions are used to generate the a-lithionitrile (a mixed Thorpe reaction). When pentanenitrile was treated with LDA and condensed with benzonitrile, 2-cyano-l-phenyl-1-pentanone was the isolated product after acid hydrolysis. Nitrile enolates can also be alkylated with a variety of alkyl halides. 34... [Pg.752]


See other pages where Alkylation of Carbon via Enolates and Enamines is mentioned: [Pg.2]    [Pg.5]    [Pg.7]    [Pg.9]    [Pg.11]    [Pg.13]    [Pg.15]    [Pg.17]    [Pg.19]    [Pg.21]    [Pg.23]    [Pg.25]    [Pg.27]    [Pg.29]    [Pg.31]    [Pg.33]    [Pg.2]    [Pg.5]    [Pg.7]    [Pg.9]    [Pg.11]    [Pg.13]    [Pg.15]    [Pg.17]    [Pg.19]    [Pg.21]    [Pg.23]    [Pg.25]    [Pg.27]    [Pg.29]    [Pg.31]    [Pg.33]    [Pg.21]    [Pg.635]    [Pg.458]    [Pg.829]    [Pg.790]    [Pg.372]    [Pg.20]   


SEARCH



Alkyl carbonate

Alkylation carbon

Alkylation enamines

Alkylation of enamines

Alkylation of enolates

Alkylation of enols

Alkylations of enolates

Enamines carbon

Enol alkyl

Enol carbonates

Enolate alkylation

Enolate enamines

Enolates alkylation

Enolates, Enols and Enamines

Enols alkylation

Enols and Enamines

Of enamines

© 2024 chempedia.info