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Ketones carbon-bromine bond formation

Reaction of a,a -dibromo ketones with iron carbonyls generates a reactive three-carbon unit. The first step of the reaction is the formation of the iron enolate (CLin) via a two-electron reduction of the dibromo ketone or through an oxidative addition of the carbon-bromine bond onto iron(0). The second step is an 8, 1 or Fe ion-assisted elimination of bromide ion to form the oxyallyl intermediate (CLIV). Evidence for the production of... [Pg.134]

A rather more complex tertracyclic indole based compound lowers blood pressure by selective blockade of a 1-adrenergic receptors. Reaction of the anion from indole (72-1) with butyrolactone (72-2) leads to the scission of the carbon-oxygen bond in the reagent and the formation of the alkylated product (72-3). The acid is then cyclized onto the adjacent 2 position to give the ketone (72-4) by treatment with a Lewis acid such as polyphosphoric acid. Reaction with bromine then leads to the brominated ketone (72-5). This is subjected to reductive alkylation with ethylene... [Pg.624]

The carbonyls Fe(CO)5 and [CpFe(CO)2]+ (2) form stable cationic complexes with alkenes, which are used for both protection and activation of alkenes [1]. [CpFe(CO)2]+ (2 abbreviated as Fp+) is prepared by the reaction of cyclopentadienyl anion (1) with Fe(CO)5, followed by oxidative cleavage with bromine, and used for the protection of alkenes. The electron density of the double bond is decreased by the coordination of [CpFe(CO)2]+ and hence this bond is activated to nucleophilic attacks. Introduction of nucleophiles, such as the carbon nucleophile of malonate, to cyclopentene becomes possible via the formation of the complex 3, and the stable tftmv-er-alkyliron complex 4 of cyclopentane is prepared. The vinyl ether complex 6 is obtained easily from the a-bromoacetal 5, and reacts with an enolate of ketone 7 as an... [Pg.355]


See other pages where Ketones carbon-bromine bond formation is mentioned: [Pg.849]    [Pg.59]    [Pg.84]    [Pg.262]    [Pg.620]    [Pg.211]    [Pg.3]    [Pg.1559]    [Pg.235]    [Pg.992]    [Pg.93]    [Pg.589]    [Pg.382]    [Pg.588]    [Pg.117]    [Pg.191]    [Pg.120]    [Pg.295]    [Pg.759]    [Pg.193]    [Pg.66]   
See also in sourсe #XX -- [ Pg.484 , Pg.486 ]




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Bonded ketone

Bonding bromination

Bonding ketones

Bromine bond

Bromine formation

Bromine ketones

Carbon-bromine bond formation

Ketone bond

Ketones bromination

Ketones brominations

Ketones carbons

Ketones formation

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