Big Chemical Encyclopedia

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

Articles Figures Tables About

Claisen rearrangement Eschenmoser modification

In the particular case in which the carbonyl group belongs to a carboxylic acid derivative, such as an ester (17) or an amide (18) (or other functional groups which may be converted into it by a FGI), then they may be disconnected according to the "orthoacetate-modification" of the retro-Claisen rearrangement (Schemes 7.7 and 7.8) developed mainly by Eschenmoser [7] and Ziegler [8], independently, in the synthesis of alkaloids, and Johnson in a very simple and yet highly stereoselective synthesis of squalene [9]. [Pg.186]

Most [3,3]-sigmatropic rearrangements take place thermally, and the Cope, oxy-Cope and Claisen rearrangements are among the most important rearrangements in this class. Important variants of the Claisen rearrangement include the Johnson modification via orthoesters, the Eschenmoser modification via ketene N,O-acetals, the Ireland modification via ketene silylacetals and the Corey modification via boron ester enolates [696], The aza-Claisen rearrangement has also seen... [Pg.605]


See other pages where Claisen rearrangement Eschenmoser modification is mentioned: [Pg.514]    [Pg.221]    [Pg.294]    [Pg.294]    [Pg.99]   
See also in sourсe #XX -- [ Pg.3 , Pg.230 ]

See also in sourсe #XX -- [ Pg.3 , Pg.230 ]




SEARCH



Eschenmoser

Eschenmoser rearrangement

Eschenmoser-Claisen

Eschenmoser-Claisen rearrangement

© 2024 chempedia.info