thiosulfonic S-esters 6: Fluoride mediated alpha sulfenilation of carbonyl compounds via their trimethylsilyl enolethers.

Ketones and carboxylic acid esters are conveniently converted to their α-sulfenylated derivatives. This new procedure is likely to represent the first reliable one for regiospecific monosulfenylation of carbonyl compounds. It is based on the reaction of their trimethylsilyl enol ether derivatives with tetrabutylammonium fluoride in the presence of thiosulfonic S-esters, in anhydrous tetrahydrofuran, under mild conditions, at - 70°C for a few minutes