Treatment of α-iodocarboxylic acid derivatives with 2 equiv of triethylborane under oxygen atmosphere gives the corresponding α-hydroxy acid derivatives. This method is based on an iodine atom transfer from the ethyl radical, generated by the reaction of triethylborane and oxygen, with the α-iodocarbonyl compound. It offers several advantages over classical ionic substitution reactions: no elimination product is observed, tertiary iodides are efficiently ...