Trifluoroacetyl hypohalites, halogenation

Halogenations are strongly catalyzed by mercuric acetate or trifluoroacetate. These conditions generate acyl hypohalites, which are the active halogenating agents. The trifluoroacetyl hypohalites are very reactive reagents. Even nitrobenzene, for example, is readily brominated by trifluoroacetyl hypobromite.19... [Pg.1009]

As in the corresponding reaction of halogens with mercuric acetate in acetic acid, addition of an excess of mercuric trifiuoroacetate to a solution of bro mine or iodine in trifluoroacetic acid results in a decrease in intensity of the halogen coloration without precipitation of mercuric halide the change in colour is ascribed to the formation of trifluoroacetyl hypohalite ... [Pg.129]

Halogenation is also effected by acyl hypohalites, such as acetyl hypochlorite and trifluoroacetyl hypobromite. ... [Pg.803]

The latter is an extremely reactive species. The inductive effect of the trifluoroacetyl group makes it a good leaving group and facilitates cleavage of the O—-Br bond. The acyl hypohalites are also the active halogenating species in solutions of the hypohalous acids in carboxylic acids, where they exist in equilibrium. [Pg.565]

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