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The co-halogenation reaction of alkynes with tri-bromoisocyanuric acid in acetic acid, followed by aqueous work-up produced α,α-di-bromoketones (44-84%), while the reaction in aqueous acetonitrile in the presence of KBr produced vicinal di-bromoalkenes (66-86%). The usefulness of the methodology was demonstrated employing green metrics for the comparison of TBCA with analogous N-halo reagents in co-halogenation reactions of alkynes.

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 1 of alkenes, and also in diverse oxidation reactions 2 . TBCA is a stable solid that can be easily synthesized from isocyanuric acid, NaOH and KBr in the presence of oxone 1 . 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 rearrangement is affected by a combination of heterocyclic brominating reagents such as NBS or TBA in the presence of an appropriate base.

The molluscicidal activities of ten Baylis–Hillman adducts against Biomphalaria glabrata (Say) snails, the intermediate host of schistosomiasis, have been determined. Nine of these compounds showed significant molluscicidal activity against B. glabrata, falling below the threshold of 100 µg ml−1 set for potential molluscicidal activity by the World Health Organisation. Among these compounds, 3-hydroxy-2-methylene-3-(4-nitrophenyl)propanenitrile had the highest activity, with LC50 = 6.64 µg ml−1. Copyright © 2006 Society of Chemical Industry

A protocol for the microwave-assisted Hofmann rearrangement mediated by TBCA/KOH/MeOH was developed. Under these conditions high yields and short reaction times were observed for aromatic benzamides.