Efficient conversion of O-substituted 3-hydroxy-4-imino-oxazolidin-2-ones into O-substituted alpha-hydroxyamidoximes

An efficient and convenient two-step synthesis of O-substituted alpha-hydroxyamidoximes has been developed. The first step involves a high-yielding one-pot synthesis of the so far unknown O-substituted 3-hydroxy-4-imino-oxazolidin-2-ones by reacting cyanohydrins stepwise with 1,1'-carbonyldiimidazole and O-substituted hydroxylamines. The second step represents a novel, sodium methoxide-mediated conversion of O-substituted 3-hydroxy-4-imino-oxazolidin-2-ones into the corresponding O-substituted alpha-hydroxyamidoximes. reaction: see text]