Bromolysis and iodolysis of α,β-epoxycarboxylic acids in water catalyzed by indium halides

The ring opening of alpha,beta -epoxycarboxylic acids by bromide and iodide ions has been efficiently carried out in water in high regio- and stereoselective fashion. The iodolysis of trans-beta -monoalkylated epoxycarboxylic acids at pH 4.0 was completely ol-regioselective and anti diastereoselective. The InCl3-catalyzed iodolysis of a variety of alpha,beta -epoxycarboxylic acids at pH 1.5 gave the corresponding anti beta -iodohydrins in 88-95% yields. The one-pot synthesis of the alpha- and beta -hydroxyhexanoic acids, starting from the corresponding alpha,beta -epoxycarboxylic acid 1a by iodolysis followed by reduction of the resulting iodohydrins 4a and 4b by NaBH4-InCl3 in water, has been performed.