Halogen addition to alkene

MECHANISM OF HALOGEN ADDITION TO ALKENES HALONIUM IONS... [Pg.256]

Mechanism of Halogen Addition to Alkenes Halonium Ions... [Pg.257]

Both parts of the Lapworth mechanism enol formation and enol halogenation are new to us Let s examine them m reverse order We can understand enol halogenation by analogy to halogen addition to alkenes An enol is a very reactive kind of alkene Its carbon-carbon double bond bears an electron releasing hydroxyl group which makes it electron rich and activates it toward attack by electrophiles... [Pg.758]

Halohydrin fonnation, as depicted in Figure 6.13, is mechanistically related to halogen addition to alkenes. A halonium ion intennediate is fonned, which is attacked by water in aqueous solution. [Pg.259]

The bromonium ion postulate, made more than 75 years ago to explain the stereochemistry of halogen addition to alkenes, is a remarkable example of deductive logic in chemistry. Arguing from experimental results, chemists were able to make a hypothesis about the intimate mechanistic details of alkene electrophilic reactions. Subsequently, strong evidence supporting the mechanism came from the work of George Olah, who prepared and studied stable... [Pg.217]

In addition to the polar mechanism already considered (p. 179), halogen addition to alkenes can proceed via radical intermediates. The former is favoured by polar solvents and by the presence of Lewis acid catalysts, the latter by non-polar solvents (or in the gas phase),... [Pg.313]

See also in sourсe #XX -- [ Pg.254 , Pg.255 , Pg.256 , Pg.257 , Pg.258 , Pg.273 , Pg.307 , Pg.308 , Pg.309 ]

See also in sourсe #XX -- [ Pg.254 , Pg.255 , Pg.256 , Pg.257 , Pg.258 , Pg.273 , Pg.307 , Pg.308 , Pg.309 ]

See also in sourсe #XX -- [ Pg.254 , Pg.255 , Pg.256 , Pg.257 , Pg.258 , Pg.273 , Pg.307 , Pg.308 , Pg.309 ]

See also in sourсe #XX -- [ Pg.233 , Pg.234 , Pg.235 , Pg.250 , Pg.284 ]

See also in sourсe #XX -- [ Pg.250 , Pg.251 , Pg.252 , Pg.268 , Pg.305 , Pg.306 ]

See also in sourсe #XX -- [ Pg.234 , Pg.235 , Pg.236 , Pg.237 , Pg.250 , Pg.288 , Pg.289 ]

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