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Auwers synthesis

Auwers synthesis. Expansion of coumarones to flavonols by treatment of 2-bromo-2-(a-bromo-benzyl)coumarones with alcoholic alkali. [Pg.111]

This reaction is related to the Auwers Synthesis, Baker-Ollis Reaction, Kostanecki-Robinson Reaction dcnd Allan-Robinson Annulation. [Pg.54]

This reaction is closely related to the Baker-Venkataraman Rearrangement and Kostanecki-Robinson Reaction. Regarding the synthesis of flavone derivatives, the Allan-Robinson condensation is also related to the Algar-Flyn-Oyamada (AFO) Reaction and Auwers Synthesis. [Pg.65]

The Auwers flavone synthesis consists of treatment of dibromo-coumarones 1 with alcoholic alkali to give the flavonols 2. It can also be described as the three-step sequence of 3 — 6. [Pg.262]

There is no published mechanistic study on the Auwers flavone synthesis. The mechanism may involve the nucleophilic addition of oxonium 7, derived from 1, with hydroxide to give 8. Base-promoted ring opening of 8 could provide the putative intermediate 9, which then could undergo an intramolecular Michael addition to form 10. Expulsion of bromide ion from 10 would then give flavonol 2. [Pg.262]

In summary, the Auwers flavone synthesis has seen only very limited utility in organic synthesis. [Pg.264]

See other pages where Auwers synthesis is mentioned: [Pg.29]    [Pg.317]    [Pg.29]    [Pg.317]    [Pg.1]    [Pg.42]    [Pg.43]    [Pg.43]    [Pg.29]    [Pg.317]    [Pg.29]    [Pg.317]    [Pg.1]    [Pg.42]    [Pg.43]    [Pg.43]    [Pg.261]    [Pg.262]    [Pg.414]    [Pg.381]    [Pg.414]    [Pg.223]    [Pg.698]    [Pg.406]    [Pg.223]    [Pg.238]    [Pg.410]    [Pg.562]    [Pg.652]    [Pg.718]    [Pg.808]    [Pg.294]    [Pg.676]    [Pg.410]   
See also in sourсe #XX -- [ Pg.29 , Pg.317 ]

See also in sourсe #XX -- [ Pg.29 , Pg.317 ]



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AUWERS Flavone synthesis

Auwers

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