(LDA, THF-HMPA,-70" C) using phenylselenenyl bromide or diphenyl diselenide afforded 4a and 4b without complication. When solutions of these arylseleno esters in ethyl acetate were treated with 30% HzOz (4-6 equiv) at 0" C for 2 h, the enol pyruvates 5a and 5b were produced in 30 and 36% yields, respectively, after column chromatography. In related experiments we had occasion to prepare two other hetero-substituted selenides. ...
