Abstract:

Tribromoisocyanuric acid (Figure 1) have been recently shown to be an efficient brominating agent, due to its ability of bromenium (‘Br+’) ion transfer to unsaturated substrates. This reagent has been used in the bromination of 1,3-dicarbonyl compounds, aromatic rings, dibromination and cobromination of alkenes, and also in diverse oxidation reactions. TBCA is a stable solid that can be easily synthesized from isocyanuric acid, NaOH and KBr in the presence of oxone. It has the advantage of high atom economy in comparison to similar systems such as N-bromosuccinimide (NBS) and N-bromosaccharin (NBSac). Furthermore, in the reactions involving TBCA, isocyanuric acid left at the end of the reaction as a by-product and can be recovered by filtration and reused to produce more TBCA. The trichloroisocyanuric acid (TCCA), analogues of TBCA also have been used in the chlorination of unsatured substrates. Hiegel and coworks demonstrated of TCCA is able to convert alkynes into α,α-dichloro ketones. However, the bromination of alkynes using TBCA has not been reported yet.